Embedded native library in the JAR file

build.xml

@@ -526,11 +526,11 @@
       <src path="${test.src}"/>
       <exclude name="${tests.exclude}"/>
     </javac>
+  	<!-- Move testlibjar.so to test class folder so that it will be packaged into the test JAR -->
+  	<move file="${build.native}/libtestlibjar.so" todir="${test.classes}/${os.name}-${os.arch}"/>
     <!-- Create a jar for easy movement of tests -->
     <jar jarfile="${build}/${testjar}">
-      <fileset dir="${test.classes}">
-        <patternset refid="jar-compiled"/>
-      </fileset>
+      <fileset dir="${test.classes}"/>
     </jar>
     <mkdir dir="${build}/jws"/>
     <copy todir="${build}/jws" file="${build}/${jar}"/>

native/Makefile

@@ -60,6 +60,7 @@ endif
 LIBRARY=$(BUILD)/$(LIBPFX)jnidispatch$(JNISFX)
 TESTLIB=$(BUILD)/$(LIBPFX)testlib$(LIBSFX)
 TESTLIB2=$(BUILD)/$(LIBPFX)testlib2$(LIBSFX)
+TESTLIBJAR=$(BUILD)/$(LIBPFX)testlibjar$(LIBSFX)
 
 # Reasonable defaults based on GCC
 LIBPFX=lib
@@ -296,7 +297,7 @@ else
 	$(CC) $(CFLAGS) -c $< $(COUT)
 endif
 
-all: $(LIBRARY) $(TESTLIB) $(TESTLIB2)
+all: $(LIBRARY) $(TESTLIB) $(TESTLIB2) $(TESTLIBJAR)
 
 install:
 	mkdir $(INSTALLDIR)
@@ -321,6 +322,9 @@ endif
 $(TESTLIB2): $(BUILD)/testlib2.o
 	$(LD) $(LDFLAGS) $< $(TESTDEP)
 
+$(TESTLIBJAR): $(BUILD)/testlibjar.o
+	$(LD) $(LDFLAGS) $< $(LIBS)
+
 ifneq ($(DYNAMIC_LIBFFI),true)
 $(FFI_LIB):
 	@mkdir -p $(FFI_BUILD)

src/com/sun/jna/NativeLibrary.java

@@ -15,7 +15,10 @@
 package com.sun.jna;
 
 import java.io.File;
+import java.io.FileOutputStream;
 import java.io.FilenameFilter;
+import java.io.IOException;
+import java.io.InputStream;
 import java.lang.ref.WeakReference;
 import java.lang.ref.Reference;
 import java.lang.reflect.Method;
@@ -165,13 +168,80 @@ else if (Platform.isWindows()) {
                 try { handle = Native.open(libraryPath); }
                 catch(UnsatisfiedLinkError e2) { e = e2; }
             }
+            // As a last resort, try to extract the library from the JAR
+            if (handle == 0) {
+                final String embeddedLib = getEmbeddedLibraryPathFromJar(mapLibraryName(libraryName));
+                if (embeddedLib != null)
+                {
+                    try {
+                        handle = Native.open(embeddedLib);
+                    }
+                    catch (UnsatisfiedLinkError e2) { e = e2; }
+                }
+            }
             if (handle == 0) {
                 throw new UnsatisfiedLinkError("Unable to load library '" + libraryName + "': "
                                                + e.getMessage());
             }
         }
         return new NativeLibrary(libraryName, libraryPath, handle, options);
     }
+
+    private static String getEmbeddedLibraryPathFromJar(String libraryName)
+    {
+        // Do not extract the library from JAR if jna.nounpack=true
+        if (Boolean.getBoolean("jna.nounpack")) {
+            return null;
+        }
+        final String libraryPath = System.getProperty("os.name") + "-" + System.getProperty("os.arch") + "/";
+        File libFile;
+        try
+        {
+            libFile = extractEmbeddedLibraryResource(libraryPath, libraryName);
+        }
+        catch (IOException e)
+        {
+            return null;
+        }
+        if (libFile == null)
+        {
+            return null;
+        }
+        else
+        {
+            return libFile.getAbsolutePath();
+        }
+    }
+
+    private static File extractEmbeddedLibraryResource(String libraryPath, String libraryName) throws IOException {
+        final InputStream is = Thread.currentThread().getContextClassLoader().getResourceAsStream(libraryPath + libraryName);
+        if (is == null) {
+            return null;
+        }
+        FileOutputStream fos = null;
+        File lib = null;
+        try {
+            // Suffix is required on windows, or library fails to load
+            // Let Java pick the suffix, except on windows, to avoid
+            // problems with Web Start.
+            File dir = Native.getTempDir();
+            lib = File.createTempFile(libraryName, Platform.isWindows()?".dll":null, dir);
+            lib.deleteOnExit();
+            fos = new FileOutputStream(lib);
+            int count;
+            byte[] buf = new byte[1024];
+            while ((count = is.read(buf, 0, buf.length)) > 0) {
+                fos.write(buf, 0, count);
+            }
+        }
+        finally {
+            try { is.close(); } catch(IOException e) { }
+            if (fos != null) {
+                try { fos.close(); } catch(IOException e) { }
+            }
+        }
+        return lib;
+    }
 
     private String getLibraryName(String libraryName) {
         String simplified = libraryName;

test/com/sun/jna/NativeLibraryTest.java

@@ -17,6 +17,7 @@
 import java.util.Arrays;
 import java.util.List;
 
+import junit.framework.Assert;
 import junit.framework.TestCase;
 
 public class NativeLibraryTest extends TestCase {
@@ -190,6 +191,18 @@ public void testGetProcess() {
         // Access a common C library function
         process.getFunction("printf");
     }
+
+    public static interface TestLibraryInJar extends Library {
+        int test();
+    }
+
+    /**
+     * Tests that we can load a library which is embedded in the test JAR.
+     */
+    public void testEmbeddedLibrary() {
+        TestLibraryInJar lib = (TestLibraryInJar)Native.loadLibrary("testlibjar", TestLibraryInJar.class);
+        Assert.assertEquals(0, lib.test());
+    }
 
     public static void main(String[] args) {
         junit.textui.TestRunner.run(NativeLibraryTest.class);