Update RocksDB's Java bindings to support multiple native RocksDB builds in the same Jar file. Cross build RocksDB for linux32 and linux64 using Vagrant. Build a cross-platform fat jar that contains osx, linux32, and linux64 RocksDB static builds.

Makefile

@@ -270,6 +270,7 @@ clean:
 	-rm -rf ios-x86/* ios-arm/*
 	-find . -name "*.[oda]" -exec rm {} \;
 	-find . -type f -regex ".*\.\(\(gcda\)\|\(gcno\)\)" -exec rm {} \;
+	-rm -rf bzip2* snappy* zlib*
 tags:
 	ctags * -R
 	cscope -b `find . -name '*.cc'` `find . -name '*.h'`
@@ -510,11 +511,14 @@ ldb: tools/ldb.o $(LIBOBJECTS)
 
 JNI_NATIVE_SOURCES = ./java/rocksjni/*.cc
 JAVA_INCLUDE = -I$(JAVA_HOME)/include/ -I$(JAVA_HOME)/include/linux
-ROCKSDBJNILIB = librocksdbjni.so
+ARCH := $(shell getconf LONG_BIT)
-ROCKSDB_JAR = rocksdbjni.jar
+ROCKSDBJNILIB = librocksdbjni-linux$(ARCH).so
+ROCKSDB_JAR = rocksdbjni-linux$(ARCH).jar
+ROCKSDB_JAR_ALL = rocksdbjni-all.jar
 
 ifeq ($(PLATFORM), OS_MACOSX)
-ROCKSDBJNILIB = librocksdbjni.jnilib
+ROCKSDBJNILIB = librocksdbjni-osx.jnilib
+ROCKSDB_JAR = rocksdbjni-osx.jar
 JAVA_INCLUDE = -I/System/Library/Frameworks/JavaVM.framework/Headers/
 endif
 
@@ -549,6 +553,10 @@ rocksdbjavastatic: libz.a libbz2.a libsnappy.a
 	cd java;jar -cf $(ROCKSDB_JAR) org/rocksdb/*.class org/rocksdb/util/*.class HISTORY*.md $(ROCKSDBJNILIB)
 	
 
+rocksdbjavastaticrelease: rocksdbjavastatic
+	cd java/crossbuild && vagrant destroy -f && vagrant up
+	cd java;jar -cf $(ROCKSDB_JAR_ALL) org/rocksdb/*.class org/rocksdb/util/*.class HISTORY*.md librocksdbjni-*.so librocksdbjni-*.jnilib
+
 rocksdbjava:
 	OPT="-fPIC -DNDEBUG -O2" $(MAKE) $(LIBRARY) -j32
 	cd java;$(MAKE) java;

java/Makefile

@@ -1,12 +1,16 @@
 NATIVE_JAVA_CLASSES = org.rocksdb.RocksDB org.rocksdb.Options org.rocksdb.WriteBatch org.rocksdb.WriteBatchInternal org.rocksdb.WriteBatchTest org.rocksdb.WriteOptions org.rocksdb.BackupableDB org.rocksdb.BackupableDBOptions org.rocksdb.Statistics org.rocksdb.RocksIterator org.rocksdb.VectorMemTableConfig org.rocksdb.SkipListMemTableConfig org.rocksdb.HashLinkedListMemTableConfig org.rocksdb.HashSkipListMemTableConfig org.rocksdb.PlainTableConfig org.rocksdb.BlockBasedTableConfig org.rocksdb.ReadOptions org.rocksdb.Filter org.rocksdb.BloomFilter org.rocksdb.RestoreOptions org.rocksdb.RestoreBackupableDB org.rocksdb.RocksEnv org.rocksdb.GenericRateLimiterConfig
 
 NATIVE_INCLUDE = ./include
-ROCKSDB_JAR = rocksdbjni.jar
+ARCH := $(shell getconf LONG_BIT)
+ROCKSDB_JAR = rocksdbjni-linux$(ARCH).jar
+
+ifeq ($(PLATFORM), OS_MACOSX)
+ROCKSDB_JAR = rocksdbjni-osx.jar
+endif
 
 clean:
 	-find . -name "*.class" -exec rm {} \;
 	-find . -name "hs*.log" -exec rm {} \;
-	rm -f $(ROCKSDB_JAR)
 
 java:
 	javac org/rocksdb/util/*.java org/rocksdb/*.java

java/crossbuild/Vagrantfile

@@ -0,0 +1,25 @@
+# -*- mode: ruby -*-
+# vi: set ft=ruby :
+
+# Vagrantfile API/syntax version. Don't touch unless you know what you're doing!
+VAGRANTFILE_API_VERSION = "2"
+
+Vagrant.configure(VAGRANTFILE_API_VERSION) do |config|
+
+  config.vm.define "linux32" do |linux32|
+    linux32.vm.box = "ubuntu/trusty32"
+    linux32.vm.provision :shell, path: "build-linux.sh"
+    linux32.vm.synced_folder "../..", "/rocksdb"
+  end
+
+  config.vm.define "linux64" do |linux64|
+    linux64.vm.box = "ubuntu/trusty64"
+    linux64.vm.provision :shell, path: "build-linux.sh"
+    linux64.vm.synced_folder "../..", "/rocksdb"
+  end
+
+  config.vm.provider "virtualbox" do |v|
+    v.memory = 2048
+    v.cpus = 4
+  end
+end

java/crossbuild/build-linux.sh

@@ -0,0 +1,11 @@
+#!/usr/bin/env bash
+# install all required packages for rocksdb
+sudo apt-get update
+sudo apt-get -y install git make gcc g++ libgflags-dev libsnappy-dev zlib1g-dev libbz2-dev default-jdk
+
+# set java home so we can build rocksdb jars
+export JAVA_HOME=$(echo /usr/lib/jvm/java-7-openjdk*)
+cd /rocksdb
+make jclean clean -j 4 rocksdbjavastatic
+sudo shutdown -h now
+

java/org/rocksdb/NativeLibraryLoader.java

@@ -1,16 +1,16 @@
 package org.rocksdb;
 
 import java.io.*;
-
+import org.rocksdb.util.Environment;
 
 /**
  * This class is used to load the RocksDB shared library from within the jar.
  * The shared library is extracted to a temp folder and loaded from there.
  */
 public class NativeLibraryLoader {
-  private static String sharedLibraryName = "librocksdbjni.so";
+  private static String sharedLibraryName = Environment.getJniLibraryName("rockdsb");
   private static String tempFilePrefix = "librocksdbjni";
-  private static String tempFileSuffix = ".so";
+  private static String tempFileSuffix = "." + Environment.getJniLibraryExtension();
 
   public static void loadLibraryFromJar(String tmpDir)
       throws IOException {

java/org/rocksdb/util/Environment.java

@@ -2,6 +2,7 @@ package org.rocksdb.util;
 
 public class Environment {
   private static String OS = System.getProperty("os.name").toLowerCase();
+  private static String ARCH = System.getProperty("os.arch").toLowerCase();
 
   public static boolean isWindows() {
     return (OS.indexOf("win") >= 0);
@@ -17,6 +18,10 @@ public class Environment {
             OS.indexOf("aix") >= 0);
   }
 
+  public static boolean is64Bit() {
+    return (ARCH.indexOf("64") > 0);
+  }
+
   public static String getSharedLibraryName(String name) {
     if (isUnix()) {
       return String.format("lib%s.so", name);
@@ -28,10 +33,15 @@ public class Environment {
 
   public static String getJniLibraryName(String name) {
     if (isUnix()) {
-      return String.format("lib%s.so", name);
+      String arch = (is64Bit()) ? "64" : "32";
+      return String.format("lib%s-linux%s.so", name, arch);
     } else if (isMac()) {
-      return String.format("lib%s.jnilib", name);
+      return String.format("lib%s-osx.jnilib", name);
     }
     throw new UnsupportedOperationException();
   }
+
+  public static String getJniLibraryExtension() {
+    return (isMac()) ? ".jnilib" : ".so";
+  }
 }