From 71a98a2de655ca84aedfcf82bfbd97142958867c Mon Sep 17 00:00:00 2001
From: Klaus Reimer <k@ailis.de>
Date: Mon, 31 Oct 2011 11:02:12 +0100
Subject: [PATCH] JNI loading errors are now all logged so they are also
 visible when using the high level API and so ALL four error messages are
 displayed and not just the last one.

---
 src/main/java/de/ailis/usb4java/jni/USB.java | 27 +++++++++++++++-----
 1 file changed, 21 insertions(+), 6 deletions(-)

diff --git a/src/main/java/de/ailis/usb4java/jni/USB.java b/src/main/java/de/ailis/usb4java/jni/USB.java
index af388ec..8266e15 100644
--- a/src/main/java/de/ailis/usb4java/jni/USB.java
+++ b/src/main/java/de/ailis/usb4java/jni/USB.java
@@ -5,8 +5,13 @@
 
 package de.ailis.usb4java.jni;
 
+import java.io.PrintWriter;
+import java.io.StringWriter;
 import java.nio.ByteBuffer;
 import java.nio.ByteOrder;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.logging.Logger;
 
 
 /**
@@ -19,6 +24,9 @@ import java.nio.ByteOrder;
 
 public final class USB
 {
+    /** The logger. */
+    private static final Logger LOG = Logger.getLogger("USB");
+
     /** The maximum size of a descriptor. */
     private static final int MAX_DESCRIPTOR_SIZE = 256;
 
@@ -218,24 +226,31 @@ public final class USB
 
     static
     {
-        Throwable lastException = null;
+        final List<Throwable> errors = new ArrayList<Throwable>();
         for (final String libName : libNames)
         {
             try
             {
                 System.loadLibrary(libName);
-                lastException = null;
+                errors.clear();
                 break;
             }
             catch (final Throwable e)
             {
-                lastException = e;
+                errors.add(e);
             }
         }
-        if (lastException != null)
+        if (!errors.isEmpty())
+        {
+            final StringWriter out = new StringWriter();
+            for (final Throwable error: errors)
+            {
+                error.printStackTrace(new PrintWriter(out));
+            }
+            LOG.severe(out.toString());
             throw new RuntimeException(
-                "Unable to load JNI library of usb4java: "
-                    + lastException, lastException);
+                "Unable to load JNI library of usb4java");
+        }
     }