diff --git a/src/main/c/src/LibUsb.c b/src/main/c/src/LibUsb.c
index 8fc386b..ed2feff 100644
--- a/src/main/c/src/LibUsb.c
+++ b/src/main/c/src/LibUsb.c
@@ -239,11 +239,11 @@ JNIEXPORT jint JNICALL METHOD_NAME(LibUsb, getDeviceSpeed)
 }
 
 /**
- * int getMaxPacketSize(Device, int)
+ * int getMaxPacketSize(Device, byte)
  */
 JNIEXPORT jint JNICALL METHOD_NAME(LibUsb, getMaxPacketSize)
 (
-    JNIEnv *env, jclass class, jobject device, jint endpoint
+    JNIEnv *env, jclass class, jobject device, jbyte endpoint
 )
 {
     NOT_NULL(env, device, return 0);
@@ -254,11 +254,11 @@ JNIEXPORT jint JNICALL METHOD_NAME(LibUsb, getMaxPacketSize)
 }
 
 /**
- * int getMaxIsoPacketSize(Device, int)
+ * int getMaxIsoPacketSize(Device, byte)
  */
 JNIEXPORT jint JNICALL METHOD_NAME(LibUsb, getMaxIsoPacketSize)
 (
-    JNIEnv *env, jclass class, jobject device, jint endpoint
+    JNIEnv *env, jclass class, jobject device, jbyte endpoint
 )
 {
     NOT_NULL(env, device, return 0);
@@ -320,12 +320,12 @@ JNIEXPORT jint JNICALL METHOD_NAME(LibUsb, open)
 }
 
 /**
- * DeviceHandle openDeviceWithVidPid(Context, int, int)
+ * DeviceHandle openDeviceWithVidPid(Context, short, short)
  */
 JNIEXPORT jobject JNICALL METHOD_NAME(LibUsb, openDeviceWithVidPid)
 (
-    JNIEnv *env, jclass class, jobject context, jint vendorId,
-    jint productId
+    JNIEnv *env, jclass class, jobject context, jshort vendorId,
+    jshort productId
 )
 {
     libusb_context *ctx = unwrapContext(env, context);
@@ -451,11 +451,11 @@ JNIEXPORT jint JNICALL METHOD_NAME(LibUsb, setInterfaceAltSetting)
 }
 
 /**
- * int clearHalt(DeviceHandle, int)
+ * int clearHalt(DeviceHandle, byte)
  */
 JNIEXPORT jint JNICALL METHOD_NAME(LibUsb, clearHalt)
 (
-    JNIEnv *env, jclass class, jobject handle, jint endpoint
+    JNIEnv *env, jclass class, jobject handle, jbyte endpoint
 )
 {
     NOT_NULL(env, handle, return 0);
@@ -559,25 +559,25 @@ JNIEXPORT jobject JNICALL METHOD_NAME(LibUsb, getVersion)
 }
 
 /**
- * int le16ToCpu(int)
+ * short le16ToCpu(short)
  */
-JNIEXPORT jint JNICALL METHOD_NAME(LibUsb, le16ToCpu)
+JNIEXPORT jshort JNICALL METHOD_NAME(LibUsb, le16ToCpu)
 (
-    JNIEnv *env, jclass class, jint x
+    JNIEnv *env, jclass class, jshort x
 )
 {
-    return libusb_le16_to_cpu((uint16_t) x);
+    return (jshort) libusb_le16_to_cpu((uint16_t) x);
 }
 
 /**
- * int cpuToLe16(int)
+ * short cpuToLe16(short)
  */
-JNIEXPORT jint JNICALL METHOD_NAME(LibUsb, cpuToLe16)
+JNIEXPORT jshort JNICALL METHOD_NAME(LibUsb, cpuToLe16)
 (
-    JNIEnv *env, jclass class, jint x
+    JNIEnv *env, jclass class, jshort x
 )
 {
-    return libusb_cpu_to_le16((uint16_t) x);
+    return (jshort) libusb_cpu_to_le16((uint16_t) x);
 }
 
 /**
@@ -646,11 +646,11 @@ JNIEXPORT jint JNICALL METHOD_NAME(LibUsb, getActiveConfigDescriptor)
 }
 
 /**
- * int getConfigDescriptor(Device, int, ConfigDescriptor)
+ * int getConfigDescriptor(Device, byte, ConfigDescriptor)
  */
 JNIEXPORT jint JNICALL METHOD_NAME(LibUsb, getConfigDescriptor)
 (
-    JNIEnv *env, jclass class, jobject device, jint index, jobject descriptor
+    JNIEnv *env, jclass class, jobject device, jbyte index, jobject descriptor
 )
 {
     NOT_NULL(env, device, return 0);
@@ -666,11 +666,11 @@ JNIEXPORT jint JNICALL METHOD_NAME(LibUsb, getConfigDescriptor)
 }
 
 /**
- * int getConfigDescriptorByValue(Device, int, ConfigDescriptor)
+ * int getConfigDescriptorByValue(Device, byte, ConfigDescriptor)
  */
 JNIEXPORT jint JNICALL METHOD_NAME(LibUsb, getConfigDescriptorByValue)
 (
-    JNIEnv *env, jclass class, jobject device, jint index, jobject descriptor
+    JNIEnv *env, jclass class, jobject device, jbyte index, jobject descriptor
 )
 {
     NOT_NULL(env, device, return 0);
@@ -704,11 +704,11 @@ JNIEXPORT void JNICALL METHOD_NAME(LibUsb, freeConfigDescriptor)
 }
 
 /**
- * int getStringDescriptorAscii(DeviceHandle, int, StringBuffer)
+ * int getStringDescriptorAscii(DeviceHandle, byte, StringBuffer)
  */
 JNIEXPORT jint JNICALL METHOD_NAME(LibUsb, getStringDescriptorAscii)
 (
-    JNIEnv *env, jclass class, jobject handle, jint index, jobject string
+    JNIEnv *env, jclass class, jobject handle, jbyte index, jobject string
 )
 {
     NOT_NULL(env, handle, return 0);
@@ -734,12 +734,12 @@ JNIEXPORT jint JNICALL METHOD_NAME(LibUsb, getStringDescriptorAscii)
 }
 
 /**
- * int controlTransfer(DeviceHandle, int, int, int, int, ByteBuffer, long)
+ * int controlTransfer(DeviceHandle, byte, byte, short, short, ByteBuffer, long)
  */
 JNIEXPORT jint JNICALL METHOD_NAME(LibUsb, controlTransfer)
 (
-    JNIEnv *env, jclass class, jobject handle, jint bmRequestType,
-    jint bRequest, jint wValue, jint wIndex, jobject data, jlong timeout
+    JNIEnv *env, jclass class, jobject handle, jbyte bmRequestType,
+    jbyte bRequest, jshort wValue, jshort wIndex, jobject data, jlong timeout
 )
 {
     NOT_NULL(env, handle, return 0);
@@ -755,11 +755,11 @@ JNIEXPORT jint JNICALL METHOD_NAME(LibUsb, controlTransfer)
 }
 
 /**
- * int bulkTransfer(DeviceHandle, int, ByteBuffer, IntBuffer, long)
+ * int bulkTransfer(DeviceHandle, byte, ByteBuffer, IntBuffer, long)
  */
 JNIEXPORT jint JNICALL METHOD_NAME(LibUsb, bulkTransfer)
 (
-    JNIEnv *env, jclass class, jobject handle, jint endpoint,
+    JNIEnv *env, jclass class, jobject handle, jbyte endpoint,
     jobject data, jobject transferred, jlong timeout
 )
 {
@@ -785,11 +785,11 @@ JNIEXPORT jint JNICALL METHOD_NAME(LibUsb, bulkTransfer)
 }
 
 /**
- * int interruptTransfer(DeviceHandle, int, ByteBuffer, IntBuffer, long)
+ * int interruptTransfer(DeviceHandle, byte, ByteBuffer, IntBuffer, long)
  */
 JNIEXPORT jint JNICALL METHOD_NAME(LibUsb, interruptTransfer)
 (
-    JNIEnv *env, jclass class, jobject handle, jint endpoint,
+    JNIEnv *env, jclass class, jobject handle, jbyte endpoint,
     jobject data, jobject transferred, jlong timeout
 )
 {
diff --git a/src/main/c/src/Transfer.c b/src/main/c/src/Transfer.c
index 74edbb4..e845b9e 100644
--- a/src/main/c/src/Transfer.c
+++ b/src/main/c/src/Transfer.c
@@ -63,11 +63,11 @@ JNIEXPORT jobject JNICALL METHOD_NAME(Transfer, devHandle)
 }
 
 /**
- * void setFlags(int)
+ * void setFlags(byte)
  */
 JNIEXPORT void JNICALL METHOD_NAME(Transfer, setFlags)
 (
-    JNIEnv *env, jobject this, jint flags
+    JNIEnv *env, jobject this, jbyte flags
 )
 {
     struct libusb_transfer *transfer = unwrapTransfer(env, this);
@@ -91,11 +91,11 @@ JNIEXPORT jbyte JNICALL METHOD_NAME(Transfer, flags)
 }
 
 /**
- * void setEndpoint(int)
+ * void setEndpoint(byte)
  */
 JNIEXPORT void JNICALL METHOD_NAME(Transfer, setEndpoint)
 (
-    JNIEnv *env, jobject this, jint endpoint
+    JNIEnv *env, jobject this, jbyte endpoint
 )
 {
     struct libusb_transfer *transfer = unwrapTransfer(env, this);
@@ -119,11 +119,11 @@ JNIEXPORT jbyte JNICALL METHOD_NAME(Transfer, endpoint)
 }
 
 /**
- * void setType(int)
+ * void setType(byte)
  */
 JNIEXPORT void JNICALL METHOD_NAME(Transfer, setType)
 (
-    JNIEnv *env, jobject this, jint type
+    JNIEnv *env, jobject this, jbyte type
 )
 {
     struct libusb_transfer *transfer = unwrapTransfer(env, this);
diff --git a/src/main/java/de/ailis/usb4java/AbstractDevice.java b/src/main/java/de/ailis/usb4java/AbstractDevice.java
index d82191e..f7eeacb 100644
--- a/src/main/java/de/ailis/usb4java/AbstractDevice.java
+++ b/src/main/java/de/ailis/usb4java/AbstractDevice.java
@@ -121,7 +121,7 @@ abstract class AbstractDevice implements UsbDevice
         for (int i = 0; i < numConfigurations; i += 1)
         {
             final ConfigDescriptor configDescriptor = new ConfigDescriptor();
-            final int result = LibUsb.getConfigDescriptor(device, i, 
+            final int result = LibUsb.getConfigDescriptor(device, (byte) i,
                 configDescriptor);
             if (result < 0)
             {
@@ -521,8 +521,8 @@ abstract class AbstractDevice implements UsbDevice
     {
         final DeviceHandle handle = open();
         final ByteBuffer buffer = ByteBuffer.allocateDirect(256);
-        final int result = LibUsb.getDescriptor(handle, LibUsb.DT_STRING, 0,
-            buffer);
+        final int result = LibUsb.getDescriptor(handle, LibUsb.DT_STRING,
+            (byte) 0, buffer);
         if (result < 0)
             throw new LibUsbException(
                 "Unable to get string descriptor languages", result);
diff --git a/src/main/java/de/ailis/usb4java/libusb/ControlSetup.java b/src/main/java/de/ailis/usb4java/libusb/ControlSetup.java
index ede48f6..e1a7a19 100644
--- a/src/main/java/de/ailis/usb4java/libusb/ControlSetup.java
+++ b/src/main/java/de/ailis/usb4java/libusb/ControlSetup.java
@@ -37,9 +37,9 @@ public final class ControlSetup
         return controlSetup.get(0);
     }
 
-    public void setBmRequestType(final int bmRequestType)
+    public void setBmRequestType(final byte bmRequestType)
     {
-        controlSetup.put(0, (byte) bmRequestType);
+        controlSetup.put(0, bmRequestType);
     }
 
     public byte bRequest()
@@ -47,9 +47,9 @@ public final class ControlSetup
         return controlSetup.get(1);
     }
 
-    public void setBRequest(final int bRequest)
+    public void setBRequest(final byte bRequest)
     {
-        controlSetup.put(1, (byte) bRequest);
+        controlSetup.put(1, bRequest);
     }
 
     public short wValue()
@@ -57,9 +57,9 @@ public final class ControlSetup
         return controlSetup.getShort(2);
     }
 
-    public void setWValue(final int wValue)
+    public void setWValue(final short wValue)
     {
-        controlSetup.putShort(2, (short) wValue);
+        controlSetup.putShort(2, wValue);
     }
 
     public short wIndex()
@@ -67,9 +67,9 @@ public final class ControlSetup
         return controlSetup.getShort(4);
     }
 
-    public void setWIndex(final int wIndex)
+    public void setWIndex(final short wIndex)
     {
-        controlSetup.putShort(4, (short) wIndex);
+        controlSetup.putShort(4, wIndex);
     }
 
     public short wLength()
@@ -77,8 +77,8 @@ public final class ControlSetup
         return controlSetup.getShort(6);
     }
 
-    public void setWLength(final int wLength)
+    public void setWLength(final short wLength)
     {
-        controlSetup.putShort(6, (short) wLength);
+        controlSetup.putShort(6, wLength);
     }
 }
diff --git a/src/main/java/de/ailis/usb4java/libusb/LibUsb.java b/src/main/java/de/ailis/usb4java/libusb/LibUsb.java
index c64b085..832357d 100644
--- a/src/main/java/de/ailis/usb4java/libusb/LibUsb.java
+++ b/src/main/java/de/ailis/usb4java/libusb/LibUsb.java
@@ -118,75 +118,75 @@ public final class LibUsb
     // Standard requests, as defined in table 9-5 of the USB 3.0 specifications.
 
     /** Request status of the specific recipient. */
-    public static final int REQUEST_GET_STATUS = 0x00;
+    public static final byte REQUEST_GET_STATUS = 0x00;
 
     /** Clear or disable a specific feature. */
-    public static final int REQUEST_CLEAR_FEATURE = 0x01;
+    public static final byte REQUEST_CLEAR_FEATURE = 0x01;
 
     /** Set or enable a specific feature. */
-    public static final int REQUEST_SET_FEATURE = 0x03;
+    public static final byte REQUEST_SET_FEATURE = 0x03;
 
     /** Set device address for all future accesses. */
-    public static final int REQUEST_SET_ADDRESS = 0x05;
+    public static final byte REQUEST_SET_ADDRESS = 0x05;
 
     /** Set device address for all future accesses. */
-    public static final int REQUEST_GET_DESCRIPTOR = 0x06;
+    public static final byte REQUEST_GET_DESCRIPTOR = 0x06;
 
     /** Set device address for all future accesses. */
-    public static final int REQUEST_SET_DESCRIPTOR = 0x07;
+    public static final byte REQUEST_SET_DESCRIPTOR = 0x07;
 
     /** Get the current device configuration value. */
-    public static final int REQUEST_GET_CONFIGURATION = 0x08;
+    public static final byte REQUEST_GET_CONFIGURATION = 0x08;
 
     /** Get the current device configuration value. */
-    public static final int REQUEST_SET_CONFIGURATION = 0x09;
+    public static final byte REQUEST_SET_CONFIGURATION = 0x09;
 
     /** Return the selected alternate setting for the specified interface. */
-    public static final int REQUEST_GET_INTERFACE = 0x0a;
+    public static final byte REQUEST_GET_INTERFACE = 0x0A;
 
     /** Select an alternate interface for the specified interface. */
-    public static final int REQUEST_SET_INTERFACE = 0x0b;
+    public static final byte REQUEST_SET_INTERFACE = 0x0B;
 
     /** Set then report an endpoint's synchronization frame. */
-    public static final int REQUEST_SYNCH_FRAME = 0x0c;
+    public static final byte REQUEST_SYNCH_FRAME = 0x0C;
 
     /** Sets both the U1 and U2 Exit Latency. */
-    public static final int REQUEST_SET_SEL = 0x30;
+    public static final byte REQUEST_SET_SEL = 0x30;
 
     /**
      * Delay from the time a host transmits a packet to the time it is received
      * by the device.
      */
-    public static final int SET_ISOCH_DELAY = 0x31;
+    public static final byte SET_ISOCH_DELAY = 0x31;
 
     // Request type bits of the bmRequestType field in control transfers.
 
     /** Standard. */
-    public static final int REQUEST_TYPE_STANDARD = 0;
+    public static final byte REQUEST_TYPE_STANDARD = 0;
 
     /** Class. */
-    public static final int REQUEST_TYPE_CLASS = 32;
+    public static final byte REQUEST_TYPE_CLASS = 32;
 
     /** Vendor. */
-    public static final int REQUEST_TYPE_VENDOR = 64;
+    public static final byte REQUEST_TYPE_VENDOR = 64;
 
     /** Reserved. */
-    public static final int REQUEST_TYPE_RESERVED = 96;
+    public static final byte REQUEST_TYPE_RESERVED = 96;
 
     // Recipient bits of the bmRequestType field in control transfers.
     // Values 4 through 31 are reserved.
 
     /** Device. */
-    public static final int RECIPIENT_DEVICE = 0x00;
+    public static final byte RECIPIENT_DEVICE = 0x00;
 
     /** Interface. */
-    public static final int RECIPIENT_INTERFACE = 0x01;
+    public static final byte RECIPIENT_INTERFACE = 0x01;
 
     /** Endpoint. */
-    public static final int RECIPIENT_ENDPOINT = 0x02;
+    public static final byte RECIPIENT_ENDPOINT = 0x02;
 
     /** Other. */
-    public static final int RECIPIENT_OTHER = 0x03;
+    public static final byte RECIPIENT_OTHER = 0x03;
 
     // Capabilities supported by this instance of libusb. Test if the loaded
     // library supports a given capability by calling hasCapability().
@@ -211,7 +211,7 @@ public final class LibUsb
      */
     public static final int CAP_SUPPORTS_DETACH_KERNEL_DRIVER = 0x0101;
 
-    public static final int CONTROL_SETUP_SIZE = 8;
+    public static final short CONTROL_SETUP_SIZE = 8;
 
     // Device and/or Interface Class codes.
 
@@ -220,61 +220,61 @@ public final class LibUsb
      * that each interface specifies its own class information and all
      * interfaces operate independently.
      */
-    public static final int CLASS_PER_INTERFACE = 0;
+    public static final byte CLASS_PER_INTERFACE = 0;
 
     /** Audio class. */
-    public static final int CLASS_AUDIO = 1;
+    public static final byte CLASS_AUDIO = 1;
 
     /** Communications class. */
-    public static final int CLASS_COMM = 2;
+    public static final byte CLASS_COMM = 2;
 
     /** Human Interface Device class. */
-    public static final int CLASS_HID = 3;
+    public static final byte CLASS_HID = 3;
 
     /** Physical. */
-    public static final int CLASS_PHYSICAL = 5;
+    public static final byte CLASS_PHYSICAL = 5;
 
     /** Image class. */
-    public static final int CLASS_PTP = 6;
+    public static final byte CLASS_PTP = 6;
 
     /** Image class. */
-    public static final int CLASS_IMAGE = 6;
+    public static final byte CLASS_IMAGE = 6;
 
     /** Printer class. */
-    public static final int CLASS_PRINTER = 7;
+    public static final byte CLASS_PRINTER = 7;
 
     /** Mass storage class. */
-    public static final int CLASS_MASS_STORAGE = 8;
+    public static final byte CLASS_MASS_STORAGE = 8;
 
     /** Hub class. */
-    public static final int CLASS_HUB = 9;
+    public static final byte CLASS_HUB = 9;
 
     /** Data class. */
-    public static final int CLASS_DATA = 10;
+    public static final byte CLASS_DATA = 10;
 
     /** Smart Card. */
-    public static final int CLASS_SMART_CARD = 0x0b;
+    public static final byte CLASS_SMART_CARD = 0x0B;
 
     /** Content Security. */
-    public static final int CLASS_CONTENT_SECURITY = 0x0d;
+    public static final byte CLASS_CONTENT_SECURITY = 0x0D;
 
     /** Video. */
-    public static final int CLASS_VIDEO = 0x0e;
+    public static final byte CLASS_VIDEO = 0x0E;
 
     /** Personal Healthcare. */
-    public static final int CLASS_PERSONAL_HEALTHCARE = 0x0f;
+    public static final byte CLASS_PERSONAL_HEALTHCARE = 0x0F;
 
     /** Diagnostic Device. */
-    public static final int CLASS_DIAGNOSTIC_DEVICE = 0xdc;
+    public static final byte CLASS_DIAGNOSTIC_DEVICE = (byte) 0xDC;
 
     /** Wireless class. */
-    public static final int CLASS_WIRELESS = 0xe0;
+    public static final byte CLASS_WIRELESS = (byte) 0xE0;
 
     /** Application class. */
-    public static final int CLASS_APPLICATION = 0xfe;
+    public static final byte CLASS_APPLICATION = (byte) 0xFE;
 
     /** Class is vendor-specific. */
-    public static final int CLASS_VENDOR_SPEC = 0xff;
+    public static final byte CLASS_VENDOR_SPEC = (byte) 0xFF;
 
     // Descriptor types as defined by the USB specification.
 
@@ -283,135 +283,135 @@ public final class LibUsb
      * 
      * @see DeviceDescriptor
      */
-    public static final int DT_DEVICE = 0x01;
+    public static final byte DT_DEVICE = 0x01;
 
     /**
      * Configuration descriptor.
      * 
      * @see ConfigDescriptor
      */
-    public static final int DT_CONFIG = 0x02;
+    public static final byte DT_CONFIG = 0x02;
 
     /** String descriptor. */
-    public static final int DT_STRING = 0x03;
+    public static final byte DT_STRING = 0x03;
 
     /**
      * Interface descriptor.
      * 
      * @see InterfaceDescriptor
      */
-    public static final int DT_INTERFACE = 0x04;
+    public static final byte DT_INTERFACE = 0x04;
 
     /**
      * Endpoint descriptor.
      * 
      * @see EndpointDescriptor
      */
-    public static final int DT_ENDPOINT = 0x05;
+    public static final byte DT_ENDPOINT = 0x05;
 
     /** HID descriptor. */
-    public static final int DT_HID = 0x21;
+    public static final byte DT_HID = 0x21;
 
     /** HID report descriptor. */
-    public static final int DT_REPORT = 0x22;
+    public static final byte DT_REPORT = 0x22;
 
     /** Physical descriptor. */
-    public static final int DT_PHYSICAL = 0x23;
+    public static final byte DT_PHYSICAL = 0x23;
 
     /** Hub descriptor. */
-    public static final int DT_HUB = 0x29;
+    public static final byte DT_HUB = 0x29;
 
     /** Hub descriptor. */
-    public static final int DT_SUPERSPEED_HUB = 0x2a;
+    public static final byte DT_SUPERSPEED_HUB = 0x2A;
 
     // Descriptor sizes per descriptor type
 
     /** Size of a device descriptor. */
-    public static final int DT_DEVICE_SIZE = 18;
+    public static final byte DT_DEVICE_SIZE = 18;
 
     /** Size of a config descriptor. */
-    public static final int DT_CONFIG_SIZE = 9;
+    public static final byte DT_CONFIG_SIZE = 9;
 
     /** Size of an interface descriptor. */
-    public static final int DT_INTERFACE_SIZE = 9;
+    public static final byte DT_INTERFACE_SIZE = 9;
 
     /** Size of an interface descriptor. */
-    public static final int DT_ENDPOINT_SIZE = 7;
+    public static final byte DT_ENDPOINT_SIZE = 7;
 
     /** Size of an interface descriptor. */
-    public static final int DT_ENDPOINT_AUDIO_SIZE = 9;
+    public static final byte DT_ENDPOINT_AUDIO_SIZE = 9;
 
     /** Size of an interface descriptor. */
-    public static final int DT_HUB_NONVAR_SIZE = 7;
+    public static final byte DT_HUB_NONVAR_SIZE = 7;
 
     // Endpoint direction. Values for bit 7 of the endpoint address scheme.
 
     /** In: device-to-host. */
-    public static final int ENDPOINT_IN = 0x80;
+    public static final byte ENDPOINT_IN = (byte) 0x80;
 
     /** Out: host-to-device. */
-    public static final int ENDPOINT_OUT = 0x00;
+    public static final byte ENDPOINT_OUT = 0x00;
 
     // === Masks =============================================================
 
     /** Endpoint address mask. */
-    public static final int ENDPOINT_ADDRESS_MASK = 0x0f;
+    public static final byte ENDPOINT_ADDRESS_MASK = 0x0F;
 
     /** Endpoint direction mask. */
-    public static final int ENDPOINT_DIR_MASK = 0x80;
+    public static final byte ENDPOINT_DIR_MASK = (byte) 0x80;
 
     /** Transfer type mask. */
-    public static final int TRANSFER_TYPE_MASK = 0x03;
+    public static final byte TRANSFER_TYPE_MASK = 0x03;
 
     // Endpoint transfer type. Values for bits 0:1 of the endpoint attributes
     // field.
 
     /** Control endpoint. */
-    public static final int TRANSFER_TYPE_CONTROL = 0;
+    public static final byte TRANSFER_TYPE_CONTROL = 0;
 
     /** Isochronous endpoint. */
-    public static final int TRANSFER_TYPE_ISOCHRONOUS = 1;
+    public static final byte TRANSFER_TYPE_ISOCHRONOUS = 1;
 
     /** Bulk endpoint. */
-    public static final int TRANSFER_TYPE_BULK = 2;
+    public static final byte TRANSFER_TYPE_BULK = 2;
 
     /** Interrupt endpoint. */
-    public static final int TRANSFER_TYPE_INTERRUPT = 3;
+    public static final byte TRANSFER_TYPE_INTERRUPT = 3;
 
     // Synchronization type for isochronous endpoints.
     // Values for bits 2:3 of the bmAttributes field in
     // EndpointDescriptor.
 
-    public static final int ISO_SYNC_TYPE_MASK = 0x0C;
+    public static final byte ISO_SYNC_TYPE_MASK = 0x0C;
 
     /** No synchronization. */
-    public static final int ISO_SYNC_TYPE_NONE = 0;
+    public static final byte ISO_SYNC_TYPE_NONE = 0;
 
     /** Asynchronous. */
-    public static final int ISO_SYNC_TYPE_ASYNC = 1;
+    public static final byte ISO_SYNC_TYPE_ASYNC = 1;
 
     /** Adaptive. */
-    public static final int ISO_SYNC_TYPE_ADAPTIVE = 2;
+    public static final byte ISO_SYNC_TYPE_ADAPTIVE = 2;
 
     /** Synchronous. */
-    public static final int ISO_SYNC_TYPE_SYNC = 3;
+    public static final byte ISO_SYNC_TYPE_SYNC = 3;
 
     // Usage type for isochronous endpoints. Values for bits 4:5 of the
     // bmAttributes field in EndpointDescriptor.
 
-    public static final int ISO_USAGE_TYPE_MASK = 0x30;
+    public static final byte ISO_USAGE_TYPE_MASK = 0x30;
 
     /** Data endpoint. */
-    public static final int ISO_USAGE_TYPE_DATA = 0;
+    public static final byte ISO_USAGE_TYPE_DATA = 0;
 
     /** Feedback endpoint. */
-    public static final int ISO_USAGE_TYPE_FEEDBACK = 1;
+    public static final byte ISO_USAGE_TYPE_FEEDBACK = 1;
 
     /** Implicit feedback Data endpoint. */
-    public static final int ISO_USAGE_TYPE_IMPLICIT = 2;
+    public static final byte ISO_USAGE_TYPE_IMPLICIT = 2;
 
     /** Report short frames as errors. */
-    public static final int TRANSFER_SHORT_NOT_OK = 1;
+    public static final byte TRANSFER_SHORT_NOT_OK = 1;
 
     // Transfer flags
 
@@ -425,7 +425,7 @@ public final class LibUsb
      * needed action to take, and it is already done by the
      * TRANSFER_FREE_TRANSFER flag.
      */
-    public static final int TRANSFER_FREE_BUFFER = 0; // Originally 2
+    public static final byte TRANSFER_FREE_BUFFER = 0; // Originally 2
 
     /**
      * Automatically call {@link #freeTransfer(Transfer)} after callback
@@ -435,7 +435,7 @@ public final class LibUsb
      * {@link #freeTransfer(Transfer)} from your transfer callback, as this will
      * result in a double-free when this flag is acted upon.
      */
-    public static final int TRANSFER_FREE_TRANSFER = 4;
+    public static final byte TRANSFER_FREE_TRANSFER = 4;
 
     /**
      * Terminate transfers that are a multiple of the endpoint's wMaxPacketSize
@@ -459,7 +459,7 @@ public final class LibUsb
      * libusb_submit_transfer() will return {@link #ERROR_NOT_SUPPORTED} for
      * every transfer where this flag is set.
      */
-    public static final int TRANSFER_ADD_ZERO_PACKET = 8;
+    public static final byte TRANSFER_ADD_ZERO_PACKET = 8;
 
     // Transfer status codes
 
@@ -700,7 +700,7 @@ public final class LibUsb
      *         does not exist {@link #ERROR_OTHER} on other failure
      */
     public static native int getMaxPacketSize(final Device device,
-        final int endpoint);
+        final byte endpoint);
 
     /**
      * Calculate the maximum packet size which a specific endpoint is capable
@@ -729,7 +729,7 @@ public final class LibUsb
      *         {@link #ERROR_OTHER} on other failure.
      */
     public static native int getMaxIsoPacketSize(final Device device,
-        final int endpoint);
+        final byte endpoint);
 
     /**
      * Increment the reference count of a device.
@@ -797,7 +797,7 @@ public final class LibUsb
      *         device could not be found.
      */
     public static native DeviceHandle openDeviceWithVidPid(
-        final Context context, final int vendorId, final int productId);
+        final Context context, final short vendorId, final short productId);
 
     /**
      * Close a device handle.
@@ -913,7 +913,7 @@ public final class LibUsb
      * 
      * @param handle
      *            A device handle.
-     * @param iface
+     * @param interfaceNumber
      *            The bInterfaceNumber of the interface you wish to claim.
      * @return 0 on success, {@link #ERROR_NOT_FOUND} if the requested interface
      *         does not exist, {@link #ERROR_BUSY} if another program or driver
@@ -921,7 +921,7 @@ public final class LibUsb
      *         has been disconnected, another error code on other failure
      */
     public static native int claimInterface(final DeviceHandle handle,
-        final int iface);
+        final int interfaceNumber);
 
     /**
      * Release an interface previously claimed with
@@ -934,14 +934,14 @@ public final class LibUsb
      * 
      * @param handle
      *            a device handle.
-     * @param iface
+     * @param interfaceNumber
      *            The bInterfaceNumber of the previously-claimed interface
      * @return 0 on success, {@link #ERROR_NOT_FOUND} if the interface was not
      *         claimed, {@link #ERROR_NO_DEVICE} if the device has been
      *         disconnected, another ERROR code on other failure
      */
     public static native int releaseInterface(final DeviceHandle handle,
-        final int iface);
+        final int interfaceNumber);
 
     /**
      * Activate an alternate setting for an interface.
@@ -989,7 +989,7 @@ public final class LibUsb
      *         disconnected, another ERROR code on other failure.
      */
     public static native int clearHalt(final DeviceHandle handle,
-        final int endpoint);
+        final byte endpoint);
 
     /**
      * Perform a USB port reset to reinitialize a device.
@@ -1127,7 +1127,7 @@ public final class LibUsb
      *            The little-endian value to convert
      * @return the value in host-endian byte order
      */
-    public static native int le16ToCpu(final int x);
+    public static native short le16ToCpu(final short x);
 
     /**
      * Convert a 16-bit value from host-endian to little-endian format.
@@ -1139,7 +1139,7 @@ public final class LibUsb
      *            The host-endian value to convert
      * @return the value in little-endian byte order
      */
-    public static native int cpuToLe16(final int x);
+    public static native short cpuToLe16(final short x);
 
     /**
      * Get the USB device descriptor for a given device.
@@ -1215,7 +1215,7 @@ public final class LibUsb
      * @see #getConfigDescriptorByValue(Device, int, ConfigDescriptor)
      */
     public static native int getConfigDescriptor(final Device device,
-        final int index, final ConfigDescriptor descriptor);
+        final byte index, final ConfigDescriptor descriptor);
 
     /**
      * Get a USB configuration descriptor with a specific bConfigurationValue.
@@ -1239,7 +1239,7 @@ public final class LibUsb
      * @see #getConfigDescriptor(Device, int, ConfigDescriptor)
      */
     public static native int getConfigDescriptorByValue(final Device device,
-        final int value, final ConfigDescriptor descriptor);
+        final byte value, final ConfigDescriptor descriptor);
 
     /**
      * Free a configuration descriptor obtained from
@@ -1267,7 +1267,7 @@ public final class LibUsb
      * @return Number of bytes returned in data, or ERROR code on failure.
      */
     public static native int getStringDescriptorAscii(
-        final DeviceHandle handle, final int index, final StringBuffer string);
+        final DeviceHandle handle, final byte index, final StringBuffer string);
 
     /**
      * A simple wrapper around
@@ -1285,7 +1285,7 @@ public final class LibUsb
      * @return The string or null if it could not be read.
      */
     public static String getStringDescriptor(final DeviceHandle handle,
-        final int index)
+        final byte index)
     {
         if ((handle == null) || (index == 0))
         {
@@ -1319,11 +1319,11 @@ public final class LibUsb
      * @return number of bytes returned in data, or ERROR code on failure
      * 
      */
-    public static int getDescriptor(final DeviceHandle handle, final int type,
-        final int index, final ByteBuffer data)
+    public static int getDescriptor(final DeviceHandle handle, final byte type,
+        final byte index, final ByteBuffer data)
     {
         return controlTransfer(handle, ENDPOINT_IN, REQUEST_GET_DESCRIPTOR,
-            (type << 8) | index, 0, data, 1000);
+            (short)((type << 8) | index), (short) 0, data, 1000);
     }
 
     /**
@@ -1345,10 +1345,10 @@ public final class LibUsb
      * @see #getStringDescriptorAscii(DeviceHandle, int, StringBuffer)
      */
     public static int getStringDescriptor(final DeviceHandle handle,
-        final int index, final int langId, final ByteBuffer data)
+        final byte index, final short langId, final ByteBuffer data)
     {
         return controlTransfer(handle, ENDPOINT_IN, REQUEST_GET_DESCRIPTOR,
-            (DT_STRING << 8) | index, langId, data, 1000);
+            (short)((DT_STRING << 8) | index), langId, data, 1000);
     }
 
     /**
@@ -1384,8 +1384,8 @@ public final class LibUsb
      *         disconnected, another ERROR code on other failures
      */
     public static native int controlTransfer(final DeviceHandle handle,
-        final int bmRequestType, final int bRequest, final int wValue,
-        final int wIndex, final ByteBuffer data, final long timeout);
+        final byte bmRequestType, final byte bRequest, final short wValue,
+        final short wIndex, final ByteBuffer data, final long timeout);
 
     /**
      * Perform a USB bulk transfer.
@@ -1429,7 +1429,7 @@ public final class LibUsb
      *         been disconnected, another ERROR code on other failures.
      */
     public static native int bulkTransfer(final DeviceHandle handle,
-        final int endpoint, final ByteBuffer data, final IntBuffer transferred,
+        final byte endpoint, final ByteBuffer data, final IntBuffer transferred,
         final long timeout);
 
     /**
@@ -1475,7 +1475,7 @@ public final class LibUsb
      *         has been disconnected, another ERROR code on other error
      */
     public static native int interruptTransfer(final DeviceHandle handle,
-        final int endpoint, final ByteBuffer data, final IntBuffer transferred,
+        final byte endpoint, final ByteBuffer data, final IntBuffer transferred,
         final long timeout);
 
     /**
@@ -2039,8 +2039,8 @@ public final class LibUsb
     }
 
     public static void fillControlSetup(final ByteBuffer buffer,
-        final int bmRequestType, final int bRequest, final int wValue,
-        final int wIndex, final int wLength)
+        final byte bmRequestType, final byte bRequest, final short wValue,
+        final short wIndex, final short wLength)
     {
         final ControlSetup setup = new ControlSetup(buffer);
         setup.setBmRequestType(bmRequestType);
@@ -2056,7 +2056,7 @@ public final class LibUsb
         final long timeout)
     {
         transfer.setDevHandle(handle);
-        transfer.setEndpoint(0);
+        transfer.setEndpoint((byte) 0);
         transfer.setType(TRANSFER_TYPE_CONTROL);
         transfer.setTimeout(timeout);
         transfer.setBuffer(buffer);
@@ -2065,11 +2065,11 @@ public final class LibUsb
 
         // Set length based on wLength from Control Setup.
         final ControlSetup setup = new ControlSetup(buffer);
-        transfer.setLength(CONTROL_SETUP_SIZE + setup.wLength());
+        transfer.setLength(CONTROL_SETUP_SIZE + (setup.wLength() & 0xFFFF));
     }
 
     public static void fillBulkTransfer(final Transfer transfer,
-        final DeviceHandle handle, final int endpoint, final ByteBuffer buffer,
+        final DeviceHandle handle, final byte endpoint, final ByteBuffer buffer,
         final TransferCallback callback, final Object userData,
         final long timeout)
     {
@@ -2083,7 +2083,7 @@ public final class LibUsb
     }
 
     public static void fillInterruptTransfer(final Transfer transfer,
-        final DeviceHandle handle, final int endpoint, final ByteBuffer buffer,
+        final DeviceHandle handle, final byte endpoint, final ByteBuffer buffer,
         final TransferCallback callback, final Object userData,
         final long timeout)
     {
@@ -2097,7 +2097,7 @@ public final class LibUsb
     }
 
     public static void fillIsoTransfer(final Transfer transfer,
-        final DeviceHandle handle, final int endpoint, final ByteBuffer buffer,
+        final DeviceHandle handle, final byte endpoint, final ByteBuffer buffer,
         final int numIsoPackets, final TransferCallback callback,
         final Object userData, final long timeout)
     {
diff --git a/src/main/java/de/ailis/usb4java/libusb/Transfer.java b/src/main/java/de/ailis/usb4java/libusb/Transfer.java
index b6c250f..10c7af1 100644
--- a/src/main/java/de/ailis/usb4java/libusb/Transfer.java
+++ b/src/main/java/de/ailis/usb4java/libusb/Transfer.java
@@ -82,7 +82,7 @@ public final class Transfer
      * @param flags
      *            The transfer flags to set.
      */
-    public native void setFlags(final int flags);
+    public native void setFlags(final byte flags);
 
     /**
      * Returns the address of the endpoint where this transfer will be sent.
@@ -97,7 +97,7 @@ public final class Transfer
      * @param endpoint
      *            The endpoint address to set
      */
-    public native void setEndpoint(final int endpoint);
+    public native void setEndpoint(final byte endpoint);
 
     /**
      * Returns the type of the endpoint.
@@ -112,7 +112,7 @@ public final class Transfer
      * @param type
      *            The endpoint type to set.
      */
-    public native void setType(final int type);
+    public native void setType(final byte type);
 
     /**
      * Returns the timeout for this transfer in milliseconds. A value of 0
diff --git a/src/main/java/de/ailis/usb4java/utils/DescriptorUtils.java b/src/main/java/de/ailis/usb4java/utils/DescriptorUtils.java
index 61ef83c..c249778 100644
--- a/src/main/java/de/ailis/usb4java/utils/DescriptorUtils.java
+++ b/src/main/java/de/ailis/usb4java/utils/DescriptorUtils.java
@@ -24,8 +24,8 @@ import de.ailis.usb4java.libusb.LibUsb;
 public final class DescriptorUtils
 {
     /** Mapping from USB class id to USB class name. */
-    private static final Map<Integer, String> CLASS_NAMES =
-        new HashMap<Integer, String>();
+    private static final Map<Byte, String> CLASS_NAMES =
+        new HashMap<Byte, String>();
 
     static
     {
@@ -66,7 +66,7 @@ public final class DescriptorUtils
      *            The numeric USB class.
      * @return The USB class name.
      */
-    public static String getUSBClassName(final int usbClass)
+    public static String getUSBClassName(final byte usbClass)
     {
         final String name = CLASS_NAMES.get(usbClass);
 
@@ -85,9 +85,9 @@ public final class DescriptorUtils
      *            The binary-coded decimal to decode.
      * @return The decoded binary-coded decimal.
      */
-    public static String decodeBCD(final int bcd)
+    public static String decodeBCD(final short bcd)
     {
-        return String.format("%x.%02x", (bcd & 0xff00) >> 8, bcd & 0xff);
+        return String.format("%x.%02x", (bcd & 0xFF00) >> 8, bcd & 0x00FF);
     }
 
     /**
@@ -169,7 +169,7 @@ public final class DescriptorUtils
             descriptor.bDescriptorType(),
             decodeBCD(descriptor.bcdUSB()),
             descriptor.bDeviceClass() & 0xff,
-            getUSBClassName(descriptor.bDeviceClass() & 0xff),
+            getUSBClassName(descriptor.bDeviceClass()),
             descriptor.bDeviceSubClass() & 0xff,
             descriptor.bDeviceProtocol() & 0xff,
             descriptor.bMaxPacketSize0() & 0xff,
@@ -246,7 +246,7 @@ public final class DescriptorUtils
             descriptor.bAlternateSetting() & 0xff,
             descriptor.bNumEndpoints() & 0xff,
             descriptor.bInterfaceClass() & 0xff,
-            getUSBClassName(descriptor.bInterfaceClass() & 0xff),
+            getUSBClassName(descriptor.bInterfaceClass()),
             descriptor.bInterfaceSubClass() & 0xff,
             descriptor.bInterfaceProtocol() & 0xff,
             descriptor.iInterface() & 0xff);
@@ -277,9 +277,9 @@ public final class DescriptorUtils
             descriptor.bEndpointAddress() & 0xf,
             ((descriptor.bEndpointAddress() & 0x80) == 0) ? ("OUT") : ("IN"),
             descriptor.bmAttributes() & 0xff,
-            getTransferTypeName(descriptor.bmAttributes() & 0xff),
-            getSynchTypeName(descriptor.bmAttributes() & 0xff),
-            getUsageTypeName(descriptor.bmAttributes() & 0xff),
+            getTransferTypeName(descriptor.bmAttributes()),
+            getSynchTypeName(descriptor.bmAttributes()),
+            getUsageTypeName(descriptor.bmAttributes()),
             descriptor.wMaxPacketSize() & 0xffff,
             descriptor.bInterval() & 0xff);
     }
@@ -292,7 +292,7 @@ public final class DescriptorUtils
      *            The endpoint attributes value.
      * @return The transfer type name.
      */
-    public static String getTransferTypeName(final int bmAttributes)
+    public static String getTransferTypeName(final byte bmAttributes)
     {
         switch (bmAttributes & LibUsb.TRANSFER_TYPE_MASK)
         {
@@ -317,7 +317,7 @@ public final class DescriptorUtils
      *            The endpoint attributes value.
      * @return The synch type name.
      */
-    public static String getSynchTypeName(final int bmAttributes)
+    public static String getSynchTypeName(final byte bmAttributes)
     {
         switch ((bmAttributes & LibUsb.ISO_SYNC_TYPE_MASK) >> 2)
         {
@@ -341,7 +341,7 @@ public final class DescriptorUtils
      *            The endpoint attributes value.
      * @return The usage type name.
      */
-    public static String getUsageTypeName(final int bmAttributes)
+    public static String getUsageTypeName(final byte bmAttributes)
     {
         switch ((bmAttributes & LibUsb.ISO_USAGE_TYPE_MASK) >> 4)
         {
diff --git a/src/test/java/de/ailis/usb4java/libusb/LibUSBDeviceTest.java b/src/test/java/de/ailis/usb4java/libusb/LibUSBDeviceTest.java
index d1816a2..5560e70 100644
--- a/src/test/java/de/ailis/usb4java/libusb/LibUSBDeviceTest.java
+++ b/src/test/java/de/ailis/usb4java/libusb/LibUSBDeviceTest.java
@@ -34,16 +34,16 @@ public class LibUSBDeviceTest
     private Device device;
 
     /** The device endpoint to test with. */
-    private int endpoint;
+    private byte endpoint;
 
     /** The value of the active configuration. */
-    private int configValue;
+    private byte configValue;
 
     /** The vendor ID of the device we test. */
-    private int vendorId;
+    private short vendorId;
 
     /** The manufacturer ID of the device we test. */
-    private int productId;
+    private short productId;
 
     /**
      * Set up the test.
@@ -51,19 +51,21 @@ public class LibUSBDeviceTest
     @Before
     public void setUp()
     {
-        this.context = new Context();
-        LibUsb.init(this.context);
+        context = new Context();
+        LibUsb.init(context);
         try
         {
-            this.device = findTestDevice();
-            if (this.device == null)
+            device = findTestDevice();
+            if (device == null)
+            {
                 throw new IllegalStateException("Need at least one USB device "
                     +
                     "with at least one endpoint to execute this test");
+            }
         }
         catch (Throwable e)
         {
-            this.device = null;
+            device = null;
         }
     }
 
@@ -75,22 +77,29 @@ public class LibUSBDeviceTest
     private Device findTestDevice()
     {
         DeviceList list = new DeviceList();
-        if (LibUsb.getDeviceList(this.context, list) <= 0) return null;
+        if (LibUsb.getDeviceList(context, list) <= 0)
+        {
+            return null;
+        }
         try
         {
             for (Device device: list)
             {
                 DeviceDescriptor descriptor = new DeviceDescriptor();
                 if (LibUsb.getDeviceDescriptor(device, descriptor) != 0)
+                {
                     continue;
-                this.vendorId = descriptor.idVendor();
-                this.productId = descriptor.idProduct();
+                }
+                vendorId = descriptor.idVendor();
+                productId = descriptor.idProduct();
                 ConfigDescriptor config = new ConfigDescriptor();
                 if (LibUsb.getActiveConfigDescriptor(device, config) < 0)
+                {
                     return null;
+                }
                 try
                 {
-                    this.configValue = config.bConfigurationValue();
+                    configValue = config.bConfigurationValue();
                     for (int j = 0; j < config.bNumInterfaces(); j++)
                     {
                         Interface iface = config.iface()[j];
@@ -100,7 +109,7 @@ public class LibUSBDeviceTest
                                 iface.altsetting()[k];
                             if (ifaceDescriptor.bNumEndpoints() > 1)
                             {
-                                this.endpoint = ifaceDescriptor.endpoint()[0].
+                                endpoint = ifaceDescriptor.endpoint()[0].
                                     bEndpointAddress();
                                 return LibUsb.refDevice(device);
                             }
@@ -126,8 +135,14 @@ public class LibUSBDeviceTest
     @After
     public void tearDown()
     {
-        if (this.device != null) LibUsb.unrefDevice(this.device);
-        if (this.context != null) LibUsb.exit(this.context);
+        if (device != null)
+        {
+            LibUsb.unrefDevice(device);
+        }
+        if (context != null)
+        {
+            LibUsb.exit(context);
+        }
     }
 
     /**
@@ -137,8 +152,8 @@ public class LibUSBDeviceTest
     public void testGetBusNumber()
     {
         assumeUsbTestsEnabled();
-        assumeNotNull(this.device);
-        assertTrue(LibUsb.getBusNumber(this.device) >= 0);
+        assumeNotNull(device);
+        assertTrue(LibUsb.getBusNumber(device) >= 0);
     }
 
     /**
@@ -148,8 +163,8 @@ public class LibUSBDeviceTest
     public void testGetPortNumber()
     {
         assumeUsbTestsEnabled();
-        assumeNotNull(this.device);
-        assertTrue(LibUsb.getPortNumber(this.device) >= 0);
+        assumeNotNull(device);
+        assertTrue(LibUsb.getPortNumber(device) >= 0);
     }
 
     /**
@@ -159,9 +174,9 @@ public class LibUSBDeviceTest
     public void testGetPortPath()
     {
         assumeUsbTestsEnabled();
-        assumeNotNull(this.device);
+        assumeNotNull(device);
         ByteBuffer path = ByteBuffer.allocateDirect(8);
-        int result = LibUsb.getPortPath(this.context, this.device, path);
+        int result = LibUsb.getPortPath(context, device, path);
         assertTrue(result > 0);
         assertTrue(result <= path.capacity());
     }
@@ -174,9 +189,9 @@ public class LibUSBDeviceTest
     public void testGetPortPathWithTooSmallBuffer()
     {
         assumeUsbTestsEnabled();
-        assumeNotNull(this.device);
+        assumeNotNull(device);
         ByteBuffer path = ByteBuffer.allocateDirect(0);
-        int result = LibUsb.getPortPath(this.context, this.device, path);
+        int result = LibUsb.getPortPath(context, device, path);
         assertEquals(LibUsb.ERROR_OVERFLOW, result);
     }
 
@@ -188,7 +203,7 @@ public class LibUSBDeviceTest
     public void testGetPortPathWithoutDevice()
     {
         assumeUsbTestsEnabled();
-        LibUsb.getPortPath(this.context, null, ByteBuffer.allocateDirect(8));
+        LibUsb.getPortPath(context, null, ByteBuffer.allocateDirect(8));
     }
 
     /**
@@ -199,7 +214,7 @@ public class LibUSBDeviceTest
     public void testGetPortPathWithoutBuffer()
     {
         assumeUsbTestsEnabled();
-        LibUsb.getPortPath(this.context, this.device, null);
+        LibUsb.getPortPath(context, device, null);
     }
 
     /**
@@ -210,9 +225,9 @@ public class LibUSBDeviceTest
     public void testGetPortPathWithUninitializedContext()
     {
         assumeUsbTestsEnabled();
-        assumeNotNull(this.device);
+        assumeNotNull(device);
         final Context context = new Context();
-        LibUsb.getPortPath(context, this.device, ByteBuffer.allocateDirect(16));
+        LibUsb.getPortPath(context, device, ByteBuffer.allocateDirect(16));
     }
 
     /**
@@ -223,7 +238,7 @@ public class LibUSBDeviceTest
     public void testGetPortPathWithUninitializedDevice()
     {
         assumeUsbTestsEnabled();
-        LibUsb.getPortPath(this.context, new Device(), ByteBuffer.allocateDirect(16));
+        LibUsb.getPortPath(context, new Device(), ByteBuffer.allocateDirect(16));
     }
 
     /**
@@ -233,17 +248,17 @@ public class LibUSBDeviceTest
     public void testGetParent()
     {
         assumeUsbTestsEnabled();
-        assumeNotNull(this.device);
+        assumeNotNull(device);
         DeviceList list = new DeviceList();
-        LibUsb.getDeviceList(this.context, list);
+        LibUsb.getDeviceList(context, list);
         try
         {
-            Device parent = LibUsb.getParent(this.device);
+            Device parent = LibUsb.getParent(device);
 
             // We cannot test anything else here. Parent can be null if our
             // test device is a root device. We just make sure that it can't
             // be the device itself.
-            assertNotEquals(parent, this.device);
+            assertNotEquals(parent, device);
         }
         finally
         {
@@ -268,8 +283,8 @@ public class LibUSBDeviceTest
     public void testGetDeviceAddress()
     {
         assumeUsbTestsEnabled();
-        assumeNotNull(this.device);
-        assertTrue(LibUsb.getDeviceAddress(this.device) >= 0);
+        assumeNotNull(device);
+        assertTrue(LibUsb.getDeviceAddress(device) >= 0);
     }
 
     /**
@@ -290,9 +305,9 @@ public class LibUSBDeviceTest
     public void testGetDeviceSpeed()
     {
         assumeUsbTestsEnabled();
-        assumeNotNull(this.device);
-        int speed = LibUsb.getDeviceSpeed(this.device);
-        assertTrue(speed >= LibUsb.SPEED_UNKNOWN && speed <= LibUsb.SPEED_SUPER);
+        assumeNotNull(device);
+        int speed = LibUsb.getDeviceSpeed(device);
+        assertTrue((speed >= LibUsb.SPEED_UNKNOWN) && (speed <= LibUsb.SPEED_SUPER));
     }
 
     /**
@@ -306,71 +321,71 @@ public class LibUSBDeviceTest
     }
 
     /**
-     * Tests the {@link LibUsb#getMaxPacketSize(Device, int)} method.
+     * Tests the {@link LibUsb#getMaxPacketSize(Device, byte)} method.
      */
     @Test
     public void testGetMaxPacketSizeWithInvalidEndpoint()
     {
         assumeUsbTestsEnabled();
-        assumeNotNull(this.device);
+        assumeNotNull(device);
         assertEquals(LibUsb.ERROR_NOT_FOUND,
-            LibUsb.getMaxPacketSize(this.device, 0));
+            LibUsb.getMaxPacketSize(device, (byte) 0));
     }
 
     /**
-     * Tests the {@link LibUsb#getMaxPacketSize(Device, int)} method.
+     * Tests the {@link LibUsb#getMaxPacketSize(Device, byte)} method.
      */
     @Test
     public void testGetMaxPacketSize()
     {
         assumeUsbTestsEnabled();
-        assumeNotNull(this.device);
-        assertTrue(LibUsb.getMaxPacketSize(this.device, this.endpoint) > 0);
+        assumeNotNull(device);
+        assertTrue(LibUsb.getMaxPacketSize(device, endpoint) > 0);
     }
 
     /**
-     * Tests the {@link LibUsb#getMaxPacketSize(Device, int)} method without a
+     * Tests the {@link LibUsb#getMaxPacketSize(Device, byte)} method without a
      * device.
      */
     @Test(expected = IllegalArgumentException.class)
     public void testGetMaxPacketSizeWithoutDevice()
     {
         assumeUsbTestsEnabled();
-        LibUsb.getMaxPacketSize(null, 0);
+        LibUsb.getMaxPacketSize(null, (byte) 0);
     }
 
     /**
-     * Tests the {@link LibUsb#getMaxIsoPacketSize(Device, int)} method.
+     * Tests the {@link LibUsb#getMaxIsoPacketSize(Device, byte)} method.
      */
     @Test
     public void testGetMaxIsoPacketSizeWithInvalidEndpoint()
     {
         assumeUsbTestsEnabled();
-        assumeNotNull(this.device);
+        assumeNotNull(device);
         assertEquals(LibUsb.ERROR_NOT_FOUND,
-            LibUsb.getMaxIsoPacketSize(this.device, 0));
+            LibUsb.getMaxIsoPacketSize(device, (byte) 0));
     }
 
     /**
-     * Tests the {@link LibUsb#getMaxIsoPacketSize(Device, int)} method.
+     * Tests the {@link LibUsb#getMaxIsoPacketSize(Device, byte)} method.
      */
     @Test
     public void testGetMaxIsoPacketSize()
     {
         assumeUsbTestsEnabled();
-        assumeNotNull(this.device);
-        assertTrue(LibUsb.getMaxIsoPacketSize(this.device, this.endpoint) > 0);
+        assumeNotNull(device);
+        assertTrue(LibUsb.getMaxIsoPacketSize(device, endpoint) > 0);
     }
 
     /**
-     * Tests the {@link LibUsb#getMaxIsoPacketSize(Device, int)} method without
+     * Tests the {@link LibUsb#getMaxIsoPacketSize(Device, byte)} method without
      * a device.
      */
     @Test(expected = IllegalArgumentException.class)
     public void testGetMaxIsoPacketSizeWithoutDevice()
     {
         assumeUsbTestsEnabled();
-        LibUsb.getMaxIsoPacketSize(null, 0);
+        LibUsb.getMaxIsoPacketSize(null, (byte) 0);
     }
 
     /**
@@ -381,7 +396,7 @@ public class LibUSBDeviceTest
     public void testRefUnRefDevice()
     {
         assumeUsbTestsEnabled();
-        assumeNotNull(this.device);
+        assumeNotNull(device);
         Device device = LibUsb.refDevice(this.device);
         try
         {
@@ -424,10 +439,10 @@ public class LibUSBDeviceTest
     public void testOpenAndClose()
     {
         assumeUsbTestsEnabled();
-        assumeNotNull(this.device);
+        assumeNotNull(device);
         DeviceHandle handle = new DeviceHandle();
-        int result = LibUsb.open(this.device, handle);
-        assertTrue(result == LibUsb.SUCCESS || result == LibUsb.ERROR_ACCESS);
+        int result = LibUsb.open(device, handle);
+        assertTrue((result == LibUsb.SUCCESS) || (result == LibUsb.ERROR_ACCESS));
         if (result == LibUsb.SUCCESS)
         {
             LibUsb.close(handle);
@@ -464,7 +479,7 @@ public class LibUSBDeviceTest
     public void testOpenWithoutHandle()
     {
         assumeUsbTestsEnabled();
-        LibUsb.open(this.device, null);
+        LibUsb.open(device, null);
     }
 
     /**
@@ -486,9 +501,12 @@ public class LibUSBDeviceTest
     public void testOpenDeviceWithVidPid()
     {
         assumeUsbTestsEnabled();
-        DeviceHandle handle = LibUsb.openDeviceWithVidPid(this.context,
-            this.vendorId, this.productId);
-        if (handle != null) LibUsb.close(handle);
+        DeviceHandle handle = LibUsb.openDeviceWithVidPid(context,
+            vendorId, productId);
+        if (handle != null)
+        {
+            LibUsb.close(handle);
+        }
     }
 
     /**
@@ -570,14 +588,14 @@ public class LibUSBDeviceTest
     }
 
     /**
-     * Tests the {@link LibUsb#clearHalt(DeviceHandle, int)} method without a
+     * Tests the {@link LibUsb#clearHalt(DeviceHandle, byte)} method without a
      * handle.
      */
     @Test(expected = IllegalArgumentException.class)
     public void testClearHaltWithoutHandle()
     {
         assumeUsbTestsEnabled();
-        LibUsb.clearHalt(null, 0);
+        LibUsb.clearHalt(null, (byte) 0);
     }
 
     /**
@@ -643,7 +661,7 @@ public class LibUSBDeviceTest
     public void testGetDeviceDescriptorWithoutDescriptor()
     {
         assumeUsbTestsEnabled();
-        LibUsb.getDeviceDescriptor(this.device, null);
+        LibUsb.getDeviceDescriptor(device, null);
     }
 
     /**
@@ -658,9 +676,9 @@ public class LibUSBDeviceTest
     public void testGetDeviceDescriptor()
     {
         assumeUsbTestsEnabled();
-        assumeNotNull(this.device);
+        assumeNotNull(device);
         DeviceDescriptor desc = new DeviceDescriptor();
-        LibUsb.getDeviceDescriptor(this.device, desc);
+        LibUsb.getDeviceDescriptor(device, desc);
         desc.bcdDevice();
         desc.bcdUSB();
         assertEquals(LibUsb.DT_DEVICE, desc.bDescriptorType());
@@ -693,7 +711,7 @@ public class LibUSBDeviceTest
     public void testGetActiveConfigDescriptorWithoutDescriptor()
     {
         assumeUsbTestsEnabled();
-        LibUsb.getActiveConfigDescriptor(this.device, null);
+        LibUsb.getActiveConfigDescriptor(device, null);
     }
 
     /**
@@ -715,7 +733,9 @@ public class LibUSBDeviceTest
         assertTrue(desc.wTotalLength() >= desc.bLength());
 
         for (Interface iface: desc.iface())
+        {
             validateInterface(iface);
+        }
     }
 
     /**
@@ -786,9 +806,9 @@ public class LibUSBDeviceTest
     public void testGetActiveConfigDescriptor()
     {
         assumeUsbTestsEnabled();
-        assumeNotNull(this.device);
+        assumeNotNull(device);
         ConfigDescriptor desc = new ConfigDescriptor();
-        LibUsb.getActiveConfigDescriptor(this.device, desc);
+        LibUsb.getActiveConfigDescriptor(device, desc);
         try
         {
             validateConfigDescriptor(desc);
@@ -801,39 +821,39 @@ public class LibUSBDeviceTest
 
     /**
      * Tests the
-     * {@link LibUsb#getConfigDescriptor(Device, int, ConfigDescriptor)} method
+     * {@link LibUsb#getConfigDescriptor(Device, byte, ConfigDescriptor)} method
      * without a device.
      */
     @Test(expected = IllegalArgumentException.class)
     public void testGetConfigDescriptorWithoutDevice()
     {
         assumeUsbTestsEnabled();
-        LibUsb.getConfigDescriptor(null, 0, new ConfigDescriptor());
+        LibUsb.getConfigDescriptor(null, (byte) 0, new ConfigDescriptor());
     }
 
     /**
      * Tests the
-     * {@link LibUsb#getConfigDescriptor(Device, int, ConfigDescriptor)} method
+     * {@link LibUsb#getConfigDescriptor(Device, byte, ConfigDescriptor)} method
      * without a descriptor.
      */
     @Test(expected = IllegalArgumentException.class)
     public void testGetConfigDescriptorWithoutDescriptor()
     {
         assumeUsbTestsEnabled();
-        LibUsb.getConfigDescriptor(this.device, 0, null);
+        LibUsb.getConfigDescriptor(device, (byte) 0, null);
     }
 
     /**
      * Tests the
-     * {@link LibUsb#getConfigDescriptor(Device, int, ConfigDescriptor)} method.
+     * {@link LibUsb#getConfigDescriptor(Device, byte, ConfigDescriptor)} method.
      */
     @Test
     public void testGetConfigDescriptor()
     {
         assumeUsbTestsEnabled();
-        assumeNotNull(this.device);
+        assumeNotNull(device);
         ConfigDescriptor desc = new ConfigDescriptor();
-        LibUsb.getConfigDescriptor(this.device, 0, desc);
+        LibUsb.getConfigDescriptor(device, (byte) 0, desc);
         try
         {
             validateConfigDescriptor(desc);
@@ -846,40 +866,40 @@ public class LibUSBDeviceTest
 
     /**
      * Tests the
-     * {@link LibUsb#getConfigDescriptorByValue(Device, int, ConfigDescriptor)}
+     * {@link LibUsb#getConfigDescriptorByValue(Device, byte, ConfigDescriptor)}
      * method without a device.
      */
     @Test(expected = IllegalArgumentException.class)
     public void testGetConfigDescriptorByValueWithoutDevice()
     {
         assumeUsbTestsEnabled();
-        LibUsb.getConfigDescriptorByValue(null, 0, new ConfigDescriptor());
+        LibUsb.getConfigDescriptorByValue(null, (byte) 0, new ConfigDescriptor());
     }
 
     /**
      * Tests the
-     * {@link LibUsb#getConfigDescriptorByValue(Device, int, ConfigDescriptor)}
+     * {@link LibUsb#getConfigDescriptorByValue(Device, byte, ConfigDescriptor)}
      * method without a descriptor.
      */
     @Test(expected = IllegalArgumentException.class)
     public void testGetConfigDescriptorByValueWithoutDescriptor()
     {
         assumeUsbTestsEnabled();
-        LibUsb.getConfigDescriptorByValue(this.device, 0, null);
+        LibUsb.getConfigDescriptorByValue(device, (byte) 0, null);
     }
 
     /**
      * Tests the
-     * {@link LibUsb#getConfigDescriptorByValue(Device, int, ConfigDescriptor)}
+     * {@link LibUsb#getConfigDescriptorByValue(Device, byte, ConfigDescriptor)}
      * method.
      */
     @Test
     public void testGetConfigDescriptorByValue()
     {
         assumeUsbTestsEnabled();
-        assumeNotNull(this.device);
+        assumeNotNull(device);
         ConfigDescriptor desc = new ConfigDescriptor();
-        LibUsb.getConfigDescriptorByValue(this.device, this.configValue, desc);
+        LibUsb.getConfigDescriptorByValue(device, configValue, desc);
         try
         {
             validateConfigDescriptor(desc);
@@ -913,214 +933,214 @@ public class LibUSBDeviceTest
 
     /**
      * Tests the
-     * {@link LibUsb#getStringDescriptorAscii(DeviceHandle, int, StringBuffer, int)}
+     * {@link LibUsb#getStringDescriptorAscii(DeviceHandle, byte, StringBuffer)}
      * method without a handle.
      */
     @Test(expected = IllegalArgumentException.class)
     public void testGetStringDescriptorAsciiWithoutHandle()
     {
         assumeUsbTestsEnabled();
-        LibUsb.getStringDescriptorAscii(null, 0, new StringBuffer());
+        LibUsb.getStringDescriptorAscii(null, (byte) 0, new StringBuffer());
     }
 
     /**
      * Tests the
-     * {@link LibUsb#getStringDescriptorAscii(DeviceHandle, int, StringBuffer, int)}
+     * {@link LibUsb#getStringDescriptorAscii(DeviceHandle, byte, StringBuffer)}
      * method without a buffer.
      */
     @Test(expected = IllegalArgumentException.class)
     public void testGetStringDescriptorAsciiWithoutBuffer()
     {
         assumeUsbTestsEnabled();
-        LibUsb.getStringDescriptorAscii(new DeviceHandle(), 0, null);
+        LibUsb.getStringDescriptorAscii(new DeviceHandle(), (byte) 0, null);
     }
 
     /**
      * Tests the
-     * {@link LibUsb#getDescriptor(DeviceHandle, int, int, ByteBuffer)} method
+     * {@link LibUsb#getDescriptor(DeviceHandle, byte, byte, ByteBuffer)} method
      * without a handle.
      */
     @Test(expected = IllegalArgumentException.class)
     public void testGetDescriptorWithoutHandle()
     {
         assumeUsbTestsEnabled();
-        LibUsb.getDescriptor(null, 0, 0, ByteBuffer.allocate(18));
+        LibUsb.getDescriptor(null, (byte) 0, (byte) 0, ByteBuffer.allocate(18));
     }
 
     /**
      * Tests the
-     * {@link LibUsb#getDescriptor(DeviceHandle, int, int, ByteBuffer)} method
+     * {@link LibUsb#getDescriptor(DeviceHandle, byte, byte, ByteBuffer)} method
      * without a buffer.
      */
     @Test(expected = IllegalArgumentException.class)
     public void testGetDescriptorWithoutBuffer()
     {
         assumeUsbTestsEnabled();
-        LibUsb.getDescriptor(new DeviceHandle(), 0, 0, null);
+        LibUsb.getDescriptor(new DeviceHandle(), (byte) 0, (byte) 0, null);
     }
 
     /**
      * Tests the
-     * {@link LibUsb#getStringDescriptor(DeviceHandle, int, int, ByteBuffer)}
+     * {@link LibUsb#getStringDescriptor(DeviceHandle, byte, short, ByteBuffer)}
      * method without a handle.
      */
     @Test(expected = IllegalArgumentException.class)
     public void testGetStringDescriptorWithoutHandle()
     {
         assumeUsbTestsEnabled();
-        LibUsb.getStringDescriptor(null, 0, 0, ByteBuffer.allocate(18));
+        LibUsb.getStringDescriptor(null, (byte) 0, (short) 0, ByteBuffer.allocate(18));
     }
 
     /**
      * Tests the
-     * {@link LibUsb#getStringDescriptor(DeviceHandle, int, int, ByteBuffer)}
+     * {@link LibUsb#getStringDescriptor(DeviceHandle, byte, short, ByteBuffer)}
      * method without a buffer.
      */
     @Test(expected = IllegalArgumentException.class)
     public void testGetStringDescriptorWithoutBuffer()
     {
         assumeUsbTestsEnabled();
-        LibUsb.getStringDescriptor(new DeviceHandle(), 0, 0, null);
+        LibUsb.getStringDescriptor(new DeviceHandle(), (byte) 0, (short) 0, null);
     }
 
     /**
      * Tests the
-     * {@link LibUsb#controlTransfer(DeviceHandle, int, int, int, int, ByteBuffer, int)}
+     * {@link LibUsb#controlTransfer(DeviceHandle, byte, byte, short, short, ByteBuffer, long)}
      * method without a handle.
      */
     @Test(expected = IllegalArgumentException.class)
     public void testControlTransferWithoutHandle()
     {
         assumeUsbTestsEnabled();
-        LibUsb.controlTransfer(null, 0, 0, 0, 0, ByteBuffer.allocate(0), 0);
+        LibUsb.controlTransfer(null, (byte) 0, (byte) 0, (short) 0, (short) 0, ByteBuffer.allocate(0), 0);
     }
 
     /**
      * Tests the
-     * {@link LibUsb#controlTransfer(DeviceHandle, int, int, int, int, ByteBuffer, int)}
+     * {@link LibUsb#controlTransfer(DeviceHandle, byte, byte, short, short, ByteBuffer, long)}
      * method without a buffer.
      */
     @Test(expected = IllegalArgumentException.class)
     public void testControlTransferWithoutBuffer()
     {
         assumeUsbTestsEnabled();
-        LibUsb.controlTransfer(new DeviceHandle(), 0, 0, 0, 0, null, 0);
+        LibUsb.controlTransfer(new DeviceHandle(), (byte) 0, (byte) 0, (short) 0, (short) 0, null, 0);
     }
 
     /**
      * Tests the
-     * {@link LibUsb#controlTransfer(DeviceHandle, int, int, int, int, ByteBuffer, int)}
+     * {@link LibUsb#controlTransfer(DeviceHandle, byte, byte, short, short, ByteBuffer, long)}
      * method with an indirect buffer.
      */
     @Test(expected = IllegalArgumentException.class)
     public void testControlTransferWithIndirectBuffer()
     {
         assumeUsbTestsEnabled();
-        LibUsb.controlTransfer(new DeviceHandle(), 0, 0, 0, 0,
+        LibUsb.controlTransfer(new DeviceHandle(), (byte) 0, (byte) 0, (short) 0, (short) 0,
             ByteBuffer.allocate(0), 0);
     }
 
     /**
      * Tests the
-     * {@link LibUsb#bulkTransfer(DeviceHandle, int, ByteBuffer, IntBuffer, int)}
+     * {@link LibUsb#bulkTransfer(DeviceHandle, byte, ByteBuffer, IntBuffer, long)}
      * method without a handle.
      */
     @Test(expected = IllegalArgumentException.class)
     public void testBulkTransferWithoutHandle()
     {
         assumeUsbTestsEnabled();
-        LibUsb.bulkTransfer(null, 0, ByteBuffer.allocate(0),
+        LibUsb.bulkTransfer(null, (byte) 0, ByteBuffer.allocate(0),
             IntBuffer.allocate(1), 0);
     }
 
     /**
      * Tests the
-     * {@link LibUsb#bulkTransfer(DeviceHandle, int, ByteBuffer, IntBuffer, int)}
+     * {@link LibUsb#bulkTransfer(DeviceHandle, byte, ByteBuffer, IntBuffer, long)}
      * method without a data buffer.
      */
     @Test(expected = IllegalArgumentException.class)
     public void testBulkTransferWithoutDataBuffer()
     {
         assumeUsbTestsEnabled();
-        LibUsb.bulkTransfer(new DeviceHandle(), 0, null,
+        LibUsb.bulkTransfer(new DeviceHandle(), (byte) 0, null,
             IntBuffer.allocate(1), 0);
     }
 
     /**
      * Tests the
-     * {@link LibUsb#bulkTransfer(DeviceHandle, int, ByteBuffer, IntBuffer, int)}
+     * {@link LibUsb#bulkTransfer(DeviceHandle, byte, ByteBuffer, IntBuffer, long)}
      * method with an indirect data buffer.
      */
     @Test(expected = IllegalArgumentException.class)
     public void testBulkTransferWithIndirectDataBuffer()
     {
         assumeUsbTestsEnabled();
-        LibUsb.bulkTransfer(new DeviceHandle(), 0, ByteBuffer.allocate(0),
+        LibUsb.bulkTransfer(new DeviceHandle(), (byte) 0, ByteBuffer.allocate(0),
             IntBuffer.allocate(1), 0);
     }
 
     /**
      * Tests the
-     * {@link LibUsb#bulkTransfer(DeviceHandle, int, ByteBuffer, IntBuffer, int)}
+     * {@link LibUsb#bulkTransfer(DeviceHandle, byte, ByteBuffer, IntBuffer, long)}
      * method without a transferred buffer.
      */
     @Test(expected = IllegalArgumentException.class)
     public void testBulkTransferWithoutTransferredBuffer()
     {
         assumeUsbTestsEnabled();
-        LibUsb.bulkTransfer(new DeviceHandle(), 0, ByteBuffer.allocate(0),
+        LibUsb.bulkTransfer(new DeviceHandle(), (byte) 0, ByteBuffer.allocate(0),
             null, 0);
     }
 
     /**
      * Tests the
-     * {@link LibUsb#interruptTransfer(DeviceHandle, int, ByteBuffer, IntBuffer, int)}
+     * {@link LibUsb#interruptTransfer(DeviceHandle, byte, ByteBuffer, IntBuffer, long)}
      * method without a handle.
      */
     @Test(expected = IllegalArgumentException.class)
     public void testInterruptTransferWithoutHandle()
     {
         assumeUsbTestsEnabled();
-        LibUsb.interruptTransfer(null, 0, ByteBuffer.allocate(0),
+        LibUsb.interruptTransfer(null, (byte) 0, ByteBuffer.allocate(0),
             IntBuffer.allocate(1), 0);
     }
 
     /**
      * Tests the
-     * {@link LibUsb#interruptTransfer(DeviceHandle, int, ByteBuffer, IntBuffer, int)}
+     * {@link LibUsb#interruptTransfer(DeviceHandle, byte, ByteBuffer, IntBuffer, long)}
      * method without a data buffer.
      */
     @Test(expected = IllegalArgumentException.class)
     public void testInterruptTransferWithoutDataBuffer()
     {
         assumeUsbTestsEnabled();
-        LibUsb.interruptTransfer(new DeviceHandle(), 0, null,
+        LibUsb.interruptTransfer(new DeviceHandle(), (byte) 0, null,
             IntBuffer.allocate(1), 0);
     }
 
     /**
      * Tests the
-     * {@link LibUsb#interruptTransfer(DeviceHandle, int, ByteBuffer, IntBuffer, int)}
+     * {@link LibUsb#interruptTransfer(DeviceHandle, byte, ByteBuffer, IntBuffer, long)}
      * method with an indirect data buffer.
      */
     @Test(expected = IllegalArgumentException.class)
     public void testInterruptTransferWithIndirectDataBuffer()
     {
         assumeUsbTestsEnabled();
-        LibUsb.interruptTransfer(new DeviceHandle(), 0, ByteBuffer.allocate(0),
+        LibUsb.interruptTransfer(new DeviceHandle(), (byte) 0, ByteBuffer.allocate(0),
             IntBuffer.allocate(1), 0);
     }
 
     /**
      * Tests the
-     * {@link LibUsb#interruptTransfer(DeviceHandle, int, ByteBuffer, IntBuffer, int)}
+     * {@link LibUsb#interruptTransfer(DeviceHandle, byte, ByteBuffer, IntBuffer, long)}
      * method without a transferred buffer.
      */
     @Test(expected = IllegalArgumentException.class)
     public void testInterruptTransferWithoutTransferredBuffer()
     {
         assumeUsbTestsEnabled();
-        LibUsb.interruptTransfer(new DeviceHandle(), 0, ByteBuffer.allocate(0),
+        LibUsb.interruptTransfer(new DeviceHandle(), (byte) 0, ByteBuffer.allocate(0),
             null, 0);
     }
 
@@ -1133,9 +1153,9 @@ public class LibUSBDeviceTest
     {
         assumeUsbTestsEnabled();
         DeviceList list = new DeviceList();
-        assertTrue(LibUsb.getDeviceList(this.context, list) >= 0);
+        assertTrue(LibUsb.getDeviceList(context, list) >= 0);
         LibUsb.freeDeviceList(list, true);
-        
+
         try
         {
             LibUsb.freeDeviceList(list, true);
@@ -1162,7 +1182,7 @@ public class LibUSBDeviceTest
         {
             assertTrue(LibUsb.getDeviceList(null, list) >= 0);
             LibUsb.freeDeviceList(list, true);
-            
+
             try
             {
                 LibUsb.freeDeviceList(list, true);
diff --git a/src/test/java/de/ailis/usb4java/libusb/LibUSBGlobalTest.java b/src/test/java/de/ailis/usb4java/libusb/LibUSBGlobalTest.java
index eb8b2d6..930b7d0 100644
--- a/src/test/java/de/ailis/usb4java/libusb/LibUSBGlobalTest.java
+++ b/src/test/java/de/ailis/usb4java/libusb/LibUSBGlobalTest.java
@@ -16,7 +16,7 @@ import org.junit.Before;
 import org.junit.Test;
 
 /**
- * Tests the global-scope methods of the {@link LibUsb} class which need a 
+ * Tests the global-scope methods of the {@link LibUsb} class which need a
  * open USB context.
  * 
  * @author Klaus Reimer (k@ailis.de)
@@ -32,14 +32,14 @@ public class LibUSBGlobalTest
     @Before
     public void setUp()
     {
-        this.context = new Context();
+        context = new Context();
         try
         {
-            LibUsb.init(this.context);
+            LibUsb.init(context);
         }
         catch (Throwable e)
         {
-            this.context = null;
+            context = null;
         }
     }
 
@@ -49,7 +49,10 @@ public class LibUSBGlobalTest
     @After
     public void tearDown()
     {
-        if (this.context != null) LibUsb.exit(this.context);
+        if (context != null)
+        {
+            LibUsb.exit(context);
+        }
     }
 
     /**
@@ -59,11 +62,11 @@ public class LibUSBGlobalTest
     public void testSetDebug()
     {
         assumeUsbTestsEnabled();
-        LibUsb.setDebug(this.context, LibUsb.LOG_LEVEL_DEBUG);
-        LibUsb.setDebug(this.context, LibUsb.LOG_LEVEL_INFO);
-        LibUsb.setDebug(this.context, LibUsb.LOG_LEVEL_WARNING);
-        LibUsb.setDebug(this.context, LibUsb.LOG_LEVEL_ERROR);
-        LibUsb.setDebug(this.context, LibUsb.LOG_LEVEL_NONE);
+        LibUsb.setDebug(context, LibUsb.LOG_LEVEL_DEBUG);
+        LibUsb.setDebug(context, LibUsb.LOG_LEVEL_INFO);
+        LibUsb.setDebug(context, LibUsb.LOG_LEVEL_WARNING);
+        LibUsb.setDebug(context, LibUsb.LOG_LEVEL_ERROR);
+        LibUsb.setDebug(context, LibUsb.LOG_LEVEL_NONE);
     }
 
     /**
@@ -74,7 +77,7 @@ public class LibUSBGlobalTest
     {
         assumeUsbTestsEnabled();
         final DeviceList list = new DeviceList();
-        final int result = LibUsb.getDeviceList(this.context, list);
+        final int result = LibUsb.getDeviceList(context, list);
         assertTrue(
             "At least one USB device must be present for the simple unit tests",
             result > 0);
@@ -98,7 +101,7 @@ public class LibUSBGlobalTest
     public void testGetDeviceListWithoutList()
     {
         assumeUsbTestsEnabled();
-        LibUsb.getDeviceList(this.context, null);
+        LibUsb.getDeviceList(context, null);
     }
 
     /**
@@ -109,7 +112,7 @@ public class LibUSBGlobalTest
     public void testEndianConversion()
     {
         assumeUsbTestsEnabled();
-        assertEquals(0x1234, LibUsb.le16ToCpu(LibUsb.cpuToLe16(0x1234)));
+        assertEquals(0x1234, LibUsb.le16ToCpu(LibUsb.cpuToLe16((short) 0x1234)));
     }
 
     /**
diff --git a/src/test/java/de/ailis/usb4java/libusb/LibUSBTest.java b/src/test/java/de/ailis/usb4java/libusb/LibUSBTest.java
index c54d0b1..b42e2b1 100644
--- a/src/test/java/de/ailis/usb4java/libusb/LibUSBTest.java
+++ b/src/test/java/de/ailis/usb4java/libusb/LibUSBTest.java
@@ -59,9 +59,9 @@ public class LibUSBTest
         assertEquals(0x07, LibUsb.REQUEST_SET_DESCRIPTOR);
         assertEquals(0x08, LibUsb.REQUEST_GET_CONFIGURATION);
         assertEquals(0x09, LibUsb.REQUEST_SET_CONFIGURATION);
-        assertEquals(0x0a, LibUsb.REQUEST_GET_INTERFACE);
-        assertEquals(0x0b, LibUsb.REQUEST_SET_INTERFACE);
-        assertEquals(0x0c, LibUsb.REQUEST_SYNCH_FRAME);
+        assertEquals(0x0A, LibUsb.REQUEST_GET_INTERFACE);
+        assertEquals(0x0B, LibUsb.REQUEST_SET_INTERFACE);
+        assertEquals(0x0C, LibUsb.REQUEST_SYNCH_FRAME);
         assertEquals(0x30, LibUsb.REQUEST_SET_SEL);
         assertEquals(0x31, LibUsb.SET_ISOCH_DELAY);
 
@@ -108,14 +108,14 @@ public class LibUSBTest
         assertEquals(8, LibUsb.CLASS_MASS_STORAGE);
         assertEquals(9, LibUsb.CLASS_HUB);
         assertEquals(10, LibUsb.CLASS_DATA);
-        assertEquals(0x0b, LibUsb.CLASS_SMART_CARD);
-        assertEquals(0x0d, LibUsb.CLASS_CONTENT_SECURITY);
-        assertEquals(0x0e, LibUsb.CLASS_VIDEO);
-        assertEquals(0x0f, LibUsb.CLASS_PERSONAL_HEALTHCARE);
-        assertEquals(0xdc, LibUsb.CLASS_DIAGNOSTIC_DEVICE);
-        assertEquals(0xe0, LibUsb.CLASS_WIRELESS);
-        assertEquals(0xfe, LibUsb.CLASS_APPLICATION);
-        assertEquals(0xff, LibUsb.CLASS_VENDOR_SPEC);
+        assertEquals(0x0B, LibUsb.CLASS_SMART_CARD);
+        assertEquals(0x0D, LibUsb.CLASS_CONTENT_SECURITY);
+        assertEquals(0x0E, LibUsb.CLASS_VIDEO);
+        assertEquals(0x0F, LibUsb.CLASS_PERSONAL_HEALTHCARE);
+        assertEquals((byte) 0xDC, LibUsb.CLASS_DIAGNOSTIC_DEVICE);
+        assertEquals((byte) 0xE0, LibUsb.CLASS_WIRELESS);
+        assertEquals((byte) 0xFE, LibUsb.CLASS_APPLICATION);
+        assertEquals((byte) 0xFF, LibUsb.CLASS_VENDOR_SPEC);
 
         // Descriptor types
         assertEquals(0x01, LibUsb.DT_DEVICE);
@@ -127,10 +127,10 @@ public class LibUSBTest
         assertEquals(0x22, LibUsb.DT_REPORT);
         assertEquals(0x23, LibUsb.DT_PHYSICAL);
         assertEquals(0x29, LibUsb.DT_HUB);
-        assertEquals(0x2a, LibUsb.DT_SUPERSPEED_HUB);
+        assertEquals(0x2A, LibUsb.DT_SUPERSPEED_HUB);
 
         // Endpoint direction
-        assertEquals(0x80, LibUsb.ENDPOINT_IN);
+        assertEquals((byte) 0x80, LibUsb.ENDPOINT_IN);
         assertEquals(0x00, LibUsb.ENDPOINT_OUT);
 
         // Transfer types
@@ -346,25 +346,25 @@ public class LibUSBTest
     }
 
     /**
-     * Tests the {@link LibUsb#getMaxPacketSize(Device, int)} method with
+     * Tests the {@link LibUsb#getMaxPacketSize(Device, byte)} method with
      * uninitialized device.
      */
     @Test(expected = IllegalStateException.class)
     public void testMaxPacketSizeWithUninitializedDevice()
     {
         assumeUsbTestsEnabled();
-        LibUsb.getMaxPacketSize(new Device(), 0);
+        LibUsb.getMaxPacketSize(new Device(), (byte) 0);
     }
 
     /**
-     * Tests the {@link LibUsb#getMaxIsoPacketSize(Device, int)} method with
+     * Tests the {@link LibUsb#getMaxIsoPacketSize(Device, byte)} method with
      * uninitialized device.
      */
     @Test(expected = IllegalStateException.class)
     public void testMaxIsoPacketSizeWithUninitializedDevice()
     {
         assumeUsbTestsEnabled();
-        LibUsb.getMaxIsoPacketSize(new Device(), 0);
+        LibUsb.getMaxIsoPacketSize(new Device(), (byte) 0);
     }
 
     /**
@@ -478,14 +478,14 @@ public class LibUSBTest
     }
 
     /**
-     * Tests the {@link LibUsb#clearHalt(DeviceHandle, int)} method with
+     * Tests the {@link LibUsb#clearHalt(DeviceHandle, byte)} method with
      * uninitialized device handle.
      */
     @Test(expected = IllegalStateException.class)
     public void testClearHaltWithUninitializedHandle()
     {
         assumeUsbTestsEnabled();
-        LibUsb.clearHalt(new DeviceHandle(), 0);
+        LibUsb.clearHalt(new DeviceHandle(), (byte) 0);
     }
 
     /**
@@ -545,14 +545,14 @@ public class LibUSBTest
 
     /**
      * Tests the
-     * {@link LibUsb#getStringDescriptorAscii(DeviceHandle, int, StringBuffer, int)}
+     * {@link LibUsb#getStringDescriptorAscii(DeviceHandle, byte, StringBuffer)}
      * method with uninitialized device handle.
      */
     @Test(expected = IllegalStateException.class)
     public void testGetStringDescriptorAsciiWithUninitializedHandle()
     {
         assumeUsbTestsEnabled();
-        LibUsb.getStringDescriptorAscii(new DeviceHandle(), 0,
+        LibUsb.getStringDescriptorAscii(new DeviceHandle(), (byte) 0,
             new StringBuffer());
     }
 
@@ -570,26 +570,26 @@ public class LibUSBTest
 
     /**
      * Tests the
-     * {@link LibUsb#getConfigDescriptor(Device, int, ConfigDescriptor)} method
+     * {@link LibUsb#getConfigDescriptor(Device, byte, ConfigDescriptor)} method
      * with uninitialized device.
      */
     @Test(expected = IllegalStateException.class)
     public void testGetConfigDescriptorWithUninitializedDevice()
     {
         assumeUsbTestsEnabled();
-        LibUsb.getConfigDescriptor(new Device(), 0, new ConfigDescriptor());
+        LibUsb.getConfigDescriptor(new Device(), (byte) 0, new ConfigDescriptor());
     }
 
     /**
      * Tests the
-     * {@link LibUsb#getConfigDescriptorByValue(Device, int, ConfigDescriptor)}
+     * {@link LibUsb#getConfigDescriptorByValue(Device, byte, ConfigDescriptor)}
      * method with uninitialized device.
      */
     @Test(expected = IllegalStateException.class)
     public void testGetConfigDescriptorByValueWithUninitializedDevice()
     {
         assumeUsbTestsEnabled();
-        LibUsb.getConfigDescriptorByValue(new Device(), 0,
+        LibUsb.getConfigDescriptorByValue(new Device(), (byte) 0,
             new ConfigDescriptor());
     }
 
@@ -606,66 +606,66 @@ public class LibUSBTest
 
     /**
      * Tests the
-     * {@link LibUsb#getDescriptor(DeviceHandle, int, int, ByteBuffer)} method
+     * {@link LibUsb#getDescriptor(DeviceHandle, byte, byte, ByteBuffer)} method
      * with uninitialized device handle.
      */
     @Test(expected = IllegalStateException.class)
     public void testGetDescriptorWithUninitializedHandle()
     {
         assumeUsbTestsEnabled();
-        LibUsb.getDescriptor(new DeviceHandle(), 0, 0,
+        LibUsb.getDescriptor(new DeviceHandle(), (byte) 0, (byte) 0,
             ByteBuffer.allocateDirect(1));
     }
 
     /**
      * Tests the
-     * {@link LibUsb#getStringDescriptor(DeviceHandle, int, int, ByteBuffer)}
+     * {@link LibUsb#getStringDescriptor(DeviceHandle, byte, short, ByteBuffer)}
      * method with uninitialized device handle.
      */
     @Test(expected = IllegalStateException.class)
     public void testGetStringDescriptorWithUninitializedHandle()
     {
         assumeUsbTestsEnabled();
-        LibUsb.getStringDescriptor(new DeviceHandle(), 0, 0,
+        LibUsb.getStringDescriptor(new DeviceHandle(), (byte) 0, (short) 0,
             ByteBuffer.allocateDirect(1));
     }
 
     /**
      * Tests the
-     * {@link LibUsb#controlTransfer(DeviceHandle, int, int, int, int, ByteBuffer, int)}
+     * {@link LibUsb#controlTransfer(DeviceHandle, byte, byte, short, short, ByteBuffer, long)}
      * method with uninitialized device handle.
      */
     @Test(expected = IllegalStateException.class)
     public void testControlTransferWithUninitializedHandle()
     {
         assumeUsbTestsEnabled();
-        LibUsb.controlTransfer(new DeviceHandle(), 0, 0, 0, 0,
+        LibUsb.controlTransfer(new DeviceHandle(), (byte) 0, (byte) 0, (short) 0, (short) 0,
             ByteBuffer.allocateDirect(1), 0);
     }
 
     /**
      * Tests the
-     * {@link LibUsb#bulkTransfer(DeviceHandle, int, ByteBuffer, IntBuffer, int)}
+     * {@link LibUsb#bulkTransfer(DeviceHandle, byte, ByteBuffer, IntBuffer, long)}
      * method with uninitialized device handle.
      */
     @Test(expected = IllegalStateException.class)
     public void testBulkTransferWithUninitializedHandle()
     {
         assumeUsbTestsEnabled();
-        LibUsb.bulkTransfer(new DeviceHandle(), 0,
+        LibUsb.bulkTransfer(new DeviceHandle(), (byte) 0,
             ByteBuffer.allocateDirect(1), IntBuffer.allocate(1), 0);
     }
 
     /**
      * Tests the
-     * {@link LibUsb#interruptTransfer(DeviceHandle, int, ByteBuffer, IntBuffer, int)}
+     * {@link LibUsb#interruptTransfer(DeviceHandle, byte, ByteBuffer, IntBuffer, long)}
      * method with uninitialized device handle.
      */
     @Test(expected = IllegalStateException.class)
     public void testInterruptTransferWithUninitializedHandle()
     {
         assumeUsbTestsEnabled();
-        LibUsb.interruptTransfer(new DeviceHandle(), 0,
+        LibUsb.interruptTransfer(new DeviceHandle(), (byte) 0,
             ByteBuffer.allocateDirect(1), IntBuffer.allocate(1), 0);
     }
 
@@ -681,7 +681,7 @@ public class LibUSBTest
     }
 
     /**
-     * Tests {@link LibUsb#openDeviceWithVidPid(Context, int, int)} with
+     * Tests {@link LibUsb#openDeviceWithVidPid(Context, short, short)} with
      * uninitialized USB context.
      */
     @Test(expected = IllegalStateException.class)
@@ -689,7 +689,7 @@ public class LibUSBTest
     {
         assumeUsbTestsEnabled();
         final Context context = new Context();
-        LibUsb.openDeviceWithVidPid(context, 0, 0);
+        LibUsb.openDeviceWithVidPid(context, (short) 0, (short) 0);
     }
 
     /**
diff --git a/src/test/java/de/ailis/usb4java/utils/DescriptorUtilsTest.java b/src/test/java/de/ailis/usb4java/utils/DescriptorUtilsTest.java
index b9c32d9..b064e4f 100644
--- a/src/test/java/de/ailis/usb4java/utils/DescriptorUtilsTest.java
+++ b/src/test/java/de/ailis/usb4java/utils/DescriptorUtilsTest.java
@@ -26,12 +26,12 @@ import de.ailis.usb4java.libusb.LibUsb;
 public class DescriptorUtilsTest
 {
     /**
-     * Tests the {@link DescriptorUtils#decodeBCD(int)} method.
+     * Tests the {@link DescriptorUtils#decodeBCD(short)} method.
      */
     @Test
     public void testDecodeBCD()
     {
-        assertEquals("10.20", DescriptorUtils.decodeBCD(0x1020));
+        assertEquals("10.20", DescriptorUtils.decodeBCD((short) 0x1020));
     }
 
     /**
@@ -49,52 +49,52 @@ public class DescriptorUtilsTest
     }
 
     /**
-     * Tests the {@link DescriptorUtils#getSynchTypeName(int)} method.
+     * Tests the {@link DescriptorUtils#getSynchTypeName(byte)} method.
      */
     @Test
     public void testGetSynchTypeName()
     {
-        assertEquals("None", DescriptorUtils.getSynchTypeName(0));
-        assertEquals("Asynchronous", DescriptorUtils.getSynchTypeName(4));
-        assertEquals("Adaptive", DescriptorUtils.getSynchTypeName(8));
-        assertEquals("Synchronous", DescriptorUtils.getSynchTypeName(12));
+        assertEquals("None", DescriptorUtils.getSynchTypeName((byte) 0));
+        assertEquals("Asynchronous", DescriptorUtils.getSynchTypeName((byte) 4));
+        assertEquals("Adaptive", DescriptorUtils.getSynchTypeName((byte) 8));
+        assertEquals("Synchronous", DescriptorUtils.getSynchTypeName((byte) 12));
     }
 
     /**
-     * Tests the {@link DescriptorUtils#getUsageTypeName(int)} method.
+     * Tests the {@link DescriptorUtils#getUsageTypeName(byte)} method.
      */
     @Test
     public void testGetUsageTypeName()
     {
-        assertEquals("Data", DescriptorUtils.getUsageTypeName(0));
-        assertEquals("Feedback", DescriptorUtils.getUsageTypeName(16));
+        assertEquals("Data", DescriptorUtils.getUsageTypeName((byte) 0));
+        assertEquals("Feedback", DescriptorUtils.getUsageTypeName((byte) 16));
         assertEquals("Implicit Feedback Data",
-            DescriptorUtils.getUsageTypeName(32));
-        assertEquals("Reserved", DescriptorUtils.getUsageTypeName(48));
+            DescriptorUtils.getUsageTypeName((byte) 32));
+        assertEquals("Reserved", DescriptorUtils.getUsageTypeName((byte) 48));
     }
 
 
     /**
-     * Tests the {@link DescriptorUtils#getTransferTypeName(int)} method.
+     * Tests the {@link DescriptorUtils#getTransferTypeName(byte)} method.
      */
     @Test
     public void testGetTransferTypeName()
     {
-        assertEquals("Control", DescriptorUtils.getTransferTypeName(0));
-        assertEquals("Isochronous", DescriptorUtils.getTransferTypeName(1));
-        assertEquals("Bulk", DescriptorUtils.getTransferTypeName(2));
-        assertEquals("Interrupt", DescriptorUtils.getTransferTypeName(3));
+        assertEquals("Control", DescriptorUtils.getTransferTypeName((byte) 0));
+        assertEquals("Isochronous", DescriptorUtils.getTransferTypeName((byte) 1));
+        assertEquals("Bulk", DescriptorUtils.getTransferTypeName((byte) 2));
+        assertEquals("Interrupt", DescriptorUtils.getTransferTypeName((byte) 3));
     }
 
     /**
-     * Tests the {@link DescriptorUtils#getUSBClassName(int)} method.
+     * Tests the {@link DescriptorUtils#getUSBClassName(byte)} method.
      */
     @Test
     public void testGetUSBClassName()
     {
         assertEquals("Audio",
             DescriptorUtils.getUSBClassName(LibUsb.CLASS_AUDIO));
-        assertEquals("Unknown", DescriptorUtils.getUSBClassName(0x1234));
+        assertEquals("Unknown", DescriptorUtils.getUSBClassName((byte) 0xF3));
     }
 
     /**