Bug 1024: Add fallback for native-jar-file location via classpath

In situations, where the native-jar file is not located within
the same parent URI as it's java-jar file, our location mechanism fails.

This patch adds a classloader based native-jar file location mechanism as a fallback,
requiring the native jar file to be included in the users CLASSPATH.

Classloader based location algorithm in JNILibLoaderBase.addNativeJarLibsImpl(..):
  - Extract the 'module-name' from the given classFromJavaJar's package name,
    i.e. the last package-part: 'jogamp.common.Debug' -> 'common'

    Hence it is important to pass a 'classFromJavaJar',
    which last package segment reflects the module-name!

  - <os.and.arch> -> <os_and_arch_dot>, e.g. linux-amd64 -> linux.amd64 (linux/amd64)

  - Locate class 'jogamp.nativetag.<module-name>.<os_and_arch_dot>.TAG',
    e.g. 'jogamp.nativetag.common.linux.amd64.TAG'

  - Use located class's JarFile URI .. continue as usual

Injection of above mentioned TAG class via gluegen-cpptasks-base.xml macro 'native.tag.jar':
  - Creates dummy TAG.java code
  - Compiles TAG.java
  - Creates the native-jar file

Example:
      <native.tag.jar objdir="${build}/obj"
                      nativejarfile="${build}/gluegen-rt-natives-${os.and.arch}.jar"
                      manifestfile="${build}/Manifest-rt-natives.temp"
                      module="common"
                      includelibs="*gluegen-rt.${native.library.suffix}" />

Note that the manifest file uses a matching Extension-Name:
  Extension-Name: jogamp.nativetag.common

1 files changed, 1 insertions, 1 deletions

diff --git a/src/java/com/jogamp/common/os/Platform.java b/src/java/com/jogamp/common/os/Platform.java
index b8e3385..12122a2 100644
--- a/src/java/com/jogamp/common/os/Platform.java
+++ b/src/java/com/jogamp/common/os/Platform.java
@@ -200,7 +200,7 @@ public class Platform extends PlatformPropsImpl {
                 // load GluegenRT native library
                 if(_USE_TEMP_JAR_CACHE[0] && TempJarCache.initSingleton()) {
                     try {
-                        JNILibLoaderBase.addNativeJarLibs(new Class<?>[] { Platform.class }, null);
+                        JNILibLoaderBase.addNativeJarLibs(new Class<?>[] { jogamp.common.Debug.class }, null);
                     } catch (final Exception e0) {
                         // IllegalArgumentException, IOException
                         System.err.println("Caught "+e0.getClass().getSimpleName()+": "+e0.getMessage()+", while JNILibLoaderBase.addNativeJarLibs(..)");