Edit documentation

INSTALL

@@ -1,19 +1,29 @@
 [Installation note of snappy-java]
 
-= Required libraries for building snappy-java =
+If your OS platform is one of the Windows/Linux/Mac OS X (32/64 bit Intel CPUs), the installation process described here is unnecessary. Simply put snappy-java-(version).jar to your Java classpath. If your OS is not in the above list, create your own snappy-java-(version).jar file as follows. 
+
+= Required tools for building snappy-java =
 
 [For all platforms]
 
 * Java 6 (JDK1.6) http://java.sun.com/
  - set JAVA_HOME environment variable to the Java installation folder (e.g. JAVA_HOME=C:/Program Files/Java/jdk1.6.0_24 in Windows)
 * Maven 3.x http://maven.apache.org/
- - Check mvn command can be run from your command line.
+ - Check mvn command can be used from your command line.
 
-[Windows (32-bit)]
+[Windows (32/64-bit)]
 * GNU make 
 * And also tar, curl, cp, rm, grep commands are needed. (I use Cygwin for building snappy-java in Windows)
 
-[Windows (64-bit)]
+[Windows (32-bit only)]
+* Install MinGW http://www.mingw.org/
+* Set PATH to the following command in MinGW package
+ - mingw32-g++
+ - strip
+
+To build x86 (32bit) dll under 64-bit Windows, use "make win32" target.
+
+[Windows (64-bit only)]
 * Download MinGW-w64 http://sourceforge.net/projects/mingw-w64/ 
 * Set PATH to the following commands in the downloaded archive: 
  - x86_64-w64-mingw32-g++
@@ -21,22 +31,13 @@
 
 NOTICE: Do not use the Cygwin version of MinGW-w64. It fails to build assemblies for 64bit environment.
 
-[Windows (32-bit)]
-* Install MinGW http://www.mingw.org/
-* Set PATH to the following command in MinGW package
- - mingw32-g++
- - strip
-
-To build x86 (32bit) dll using 64-bit Windows, use "make win32" target.
-
 [Linux (32/64-bit)]
 * gcc-4.5.x or higher is necessary because snappy-java uses -static-libstdc++ option. 
-
+* You can build 32-bit native library with 64-bit Linux machine (do make linux32)
 
 [Mac]
 * Install gcc, make, etc. included in Mac OS X install disk. (X Code)
-* Install mercurial using Mac Porsts http://www.macports.org/
-
+* Install mercurial using Mac Ports http://www.macports.org/
 
 = Building snappy-java =
 
@@ -45,9 +46,10 @@ $ make
 
 A native library for your machine environment and a jar package target/snappy-java-(version).jar are produced in the target folder.
 
-= Building native library = 
+= Building only the native library = 
 $ make native
 
-= Rebuild native library =
+= Rebuild the native library for your platform =
 $ make clean-native native
 
+

Makefile

@@ -58,7 +58,7 @@ NATIVE_DLL:=$(NATIVE_DIR)/$(LIBNAME)
 snappy-jar-version:=snappy-java-$(shell $(JAVA) -jar lib/silk-weaver.jar find 'project(artifactId, version)' pom.xml | grep snappy-java | awk '{ print $$2; }')
 
 native: $(SNAPPY_UNPACKED) $(NATIVE_DLL) 
-snappy: $(TARGET)/$(snappy-jar-version).jar
+snappy: native $(TARGET)/$(snappy-jar-version).jar
 
 $(NATIVE_DLL): $(SNAPPY_OUT)/$(LIBNAME) 
 	@mkdir -p $(@D)

Makefile.common

@@ -23,7 +23,7 @@ OS_NAME := $(shell $(JAVA) -cp lib $(OSINFO_CLASS) --os)
 OS_ARCH := $(shell $(JAVA) -cp lib $(OSINFO_CLASS) --arch)
 LIB_FOLDER := $(shell $(JAVA) -cp lib $(OSINFO_CLASS))
 
-# Windows uses different path separators, because they hate me
+# Windows uses different path separators
 ifeq ($(OS_NAME),Windows)
 	sep := ;
 else
@@ -50,7 +50,7 @@ endif
 
 Default_CXX          := g++
 Default_STRIP        := strip
-Default_CXXFLAGS     := -I$(JAVA_HOME)/include -Ilib/inc_mac -O2 -fPIC
+Default_CXXFLAGS     := -I$(JAVA_HOME)/include -Ilib/inc_mac -O2 -fPIC -fvisibility=hidden
 Default_LINKFLAGS    := -shared -static
 Default_LIBNAME      := libsnappyjava.so
 Default_SNAPPY_FLAGS := 

lib/include/config.h

@@ -0,0 +1,5 @@
+
+#ifndef __CONFIG_H
+#define __CONFIG_H
+
+#endif // __CONFIG_H

src/main/java/org/xerial/snappy/SnappyLoader.java

@@ -124,21 +124,22 @@ public class SnappyLoader
                 try {
                     // Load a byte code 
                     byte[] byteCode = getByteCode("/org/xerial/snappy/SnappyNativeLoader.bytecode");
-                    // In addition, load the SnappyNative and SnappyException class in the system class loader
+                    // In addition, we need to load the other dependent classes (e.g., SnappyNative and SnappyException) using the system class loader
                     List<byte[]> preloadClassByteCode = new ArrayList<byte[]>(classesToPreload.length);
                     for (String each : classesToPreload) {
                         preloadClassByteCode.add(getByteCode(String.format("/%s.class", each.replaceAll("\\.", "/"))));
                     }
 
-                    // Create a new class to the system class loader
+                    // Create a new class from a byte code
                     Class< ? > classLoader = Class.forName("java.lang.ClassLoader");
                     Method defineClass = classLoader.getDeclaredMethod("defineClass", new Class[] { String.class,
                             byte[].class, int.class, int.class, ProtectionDomain.class });
 
                     ClassLoader systemClassLoader = getSystemClassLoader();
+                    // ClassLoader.defineClass is a protected method, so we have to make it accessible
                     defineClass.setAccessible(true);
                     try {
-                        // Load SnappyNativeLoader
+                        // Create a new class using a ClassLoader#defineClass
                         defineClass.invoke(systemClassLoader, nativeLoaderClassName, byteCode, 0, byteCode.length,
                                 System.class.getProtectionDomain());
 
@@ -149,16 +150,18 @@ public class SnappyLoader
                         }
                     }
                     finally {
+                        // Reset the accessibility to defineClass method
                         defineClass.setAccessible(false);
                     }
 
-                    // Load the loader class
+                    // Load the snappy loader class
                     Class< ? > loaderClass = systemClassLoader.loadClass(nativeLoaderClassName);
                     if (loaderClass != null) {
                         Method loadMethod = loaderClass.getDeclaredMethod("load", new Class[] { String.class });
                         File nativeLib = findNativeLibrary();
                         loadMethod.invoke(null, nativeLib.getAbsolutePath());
 
+                        // And also, preload the other dependent classes 
                         for (String each : classesToPreload) {
                             systemClassLoader.loadClass(each);
                         }
@@ -167,7 +170,7 @@ public class SnappyLoader
                     }
                 }
                 catch (Exception e2) {
-                    e.printStackTrace();
+                    e2.printStackTrace();
                 }
             }
 

src/test/java/org/xerial/snappy/SnappyLoaderTest.java

@@ -64,7 +64,7 @@ public class SnappyLoaderTest
 
         ProtectionDomain systemPD = System.class.getProtectionDomain();
         byte[] bytecode = cl.toBytecode();
-        //        FileOutputStream f = new FileOutputStream("src/main/java/org/xerial/snappy/SnappyNativeLoader.bytecode");
+        //        FileOutputStream f = new FileOutputStream("src/main/resources/org/xerial/snappy/SnappyNativeLoader.bytecode");
         //        f.write(bytecode);
         //        f.close();