Plugin java jni support (#9575)

Summary:
Extend the plugin architecture to allow for the inclusion, building and testing of Java and JNI components of a plugin. This will cause the JAR built by `$ make rocksdbjava` to include the extra functionality provided by the plugin, and will cause `$ make jtest` to add the java tests provided by the plugin to the tests built and run by Java testing.

The plugin's `<plugin>.mk` file can define:
```
<plugin>_JNI_NATIVE_SOURCES
<plugin>_NATIVE_JAVA_CLASSES
<plugin>_JAVA_TESTS
```
The plugin should provide java/src, java/test and java/rocksjni directories. When a plugin is required to be build it must be named in the ROCKSDB_PLUGINS environment variable (as per the plugin architecture). This now has the effect of adding the files specified by the above definitions to the appropriate parts of the build.

An example of a plugin with a Java component can be found as part of the hdfs plugin in https://github.com/riversand963/rocksdb-hdfs-env - at the time of writing the Java part of this fails tests, and needs a little work to complete, but it builds correctly under the plugin model.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9575

Reviewed By: hx235

Differential Revision: D34253948

Pulled By: riversand963

fbshipit-source-id: b3dde5da06f3d3c25c54246892097ae2a369b42d

Makefile

@@ -239,9 +239,19 @@ include $(ROCKSDB_PLUGIN_MKS)
 ROCKSDB_PLUGIN_SOURCES = $(foreach plugin, $(ROCKSDB_PLUGINS), $(foreach source, $($(plugin)_SOURCES), plugin/$(plugin)/$(source)))
 ROCKSDB_PLUGIN_HEADERS = $(foreach plugin, $(ROCKSDB_PLUGINS), $(foreach header, $($(plugin)_HEADERS), plugin/$(plugin)/$(header)))
 ROCKSDB_PLUGIN_PKGCONFIG_REQUIRES = $(foreach plugin, $(ROCKSDB_PLUGINS), $($(plugin)_PKGCONFIG_REQUIRES))
-PLATFORM_LDFLAGS += $(foreach plugin, $(ROCKSDB_PLUGINS), $($(plugin)_LDFLAGS))
 CXXFLAGS += $(foreach plugin, $(ROCKSDB_PLUGINS), $($(plugin)_CXXFLAGS))
 
+# Patch up the link flags for JNI from the plugins
+ROCKSDB_PLUGIN_LDFLAGS = $(foreach plugin, $(ROCKSDB_PLUGINS), $($(plugin)_LDFLAGS))
+PLATFORM_LDFLAGS += $(ROCKSDB_PLUGIN_LDFLAGS)
+JAVA_LDFLAGS += $(ROCKSDB_PLUGIN_LDFLAGS)
+JAVA_STATIC_LDFLAGS += $(ROCKSDB_PLUGIN_LDFLAGS)
+
+# Patch up the list of java native sources with files from the plugins
+ROCKSDB_PLUGIN_JNI_NATIVE_SOURCES = $(foreach plugin, $(ROCKSDB_PLUGINS), $(foreach source, $($(plugin)_JNI_NATIVE_SOURCES), plugin/$(plugin)/$(source)))
+ALL_JNI_NATIVE_SOURCES = $(JNI_NATIVE_SOURCES) $(ROCKSDB_PLUGIN_JNI_NATIVE_SOURCES)
+ROCKSDB_PLUGIN_JNI_CXX_INCLUDEFLAGS = $(foreach plugin, $(ROCKSDB_PLUGINS), -I./plugin/$(plugin))
+
 ifneq ($(strip $(ROCKSDB_PLUGIN_PKGCONFIG_REQUIRES)),)
 LDFLAGS := $(LDFLAGS) $(shell pkg-config --libs $(ROCKSDB_PLUGIN_PKGCONFIG_REQUIRES))
 ifneq ($(.SHELLSTATUS),0)
@@ -2272,7 +2282,7 @@ rocksdbjavastatic_javalib:
 	cd java; SHA256_CMD='$(SHA256_CMD)' $(MAKE) javalib
 	rm -f java/target/$(ROCKSDBJNILIB)
 	$(CXX) $(CXXFLAGS) -I./java/. $(JAVA_INCLUDE) -shared -fPIC \
-	  -o ./java/target/$(ROCKSDBJNILIB) $(JNI_NATIVE_SOURCES) \
+	  -o ./java/target/$(ROCKSDBJNILIB) $(ALL_JNI_NATIVE_SOURCES) \
 	  $(LIB_OBJECTS) $(COVERAGEFLAGS) \
 	  $(JAVA_COMPRESSIONS) $(JAVA_STATIC_LDFLAGS)
 	cd java/target;if [ "$(DEBUG_LEVEL)" == "0" ]; then \
@@ -2381,7 +2391,7 @@ ifeq ($(JAVA_HOME),)
 endif
 	$(AM_V_GEN)cd java; SHA256_CMD='$(SHA256_CMD)' $(MAKE) javalib;
 	$(AM_V_at)rm -f ./java/target/$(ROCKSDBJNILIB)
-	$(AM_V_at)$(CXX) $(CXXFLAGS) -I./java/. $(JAVA_INCLUDE) -shared -fPIC -o ./java/target/$(ROCKSDBJNILIB) $(JNI_NATIVE_SOURCES) $(LIB_OBJECTS) $(JAVA_LDFLAGS) $(COVERAGEFLAGS)
+	$(AM_V_at)$(CXX) $(CXXFLAGS) -I./java/. -I./java/rocksjni $(JAVA_INCLUDE) $(ROCKSDB_PLUGIN_JNI_CXX_INCLUDEFLAGS) -shared -fPIC -o ./java/target/$(ROCKSDBJNILIB) $(ALL_JNI_NATIVE_SOURCES) $(LIB_OBJECTS) $(JAVA_LDFLAGS) $(COVERAGEFLAGS)
 	$(AM_V_at)cd java; $(JAR_CMD) -cf target/$(ROCKSDB_JAR) HISTORY*.md
 	$(AM_V_at)cd java/target; $(JAR_CMD) -uf $(ROCKSDB_JAR) $(ROCKSDBJNILIB)
 	$(AM_V_at)cd java/target/classes; $(JAR_CMD) -uf ../$(ROCKSDB_JAR) org/rocksdb/*.class org/rocksdb/util/*.class

java/Makefile

@@ -276,6 +276,26 @@ JAVA_ARGS ?=
 
 JAVAC_ARGS ?=
 
+# Read plugin configuration
+PLUGIN_PATH = ../plugin
+ROCKSDB_PLUGIN_MKS = $(foreach plugin, $(ROCKSDB_PLUGINS), $(PLUGIN_PATH)/$(plugin)/*.mk)
+include $(ROCKSDB_PLUGIN_MKS)
+
+# Add paths to Java sources in plugins
+ROCKSDB_PLUGIN_JAVA_ROOTS = $(foreach plugin, $(ROCKSDB_PLUGINS), $(PLUGIN_PATH)/$(plugin)/java)
+PLUGIN_SOURCES = $(foreach root, $(ROCKSDB_PLUGIN_JAVA_ROOTS), $(foreach pkg, org/rocksdb/util org/rocksdb, $(root)/$(MAIN_SRC)/$(pkg)/*.java))
+CORE_SOURCES = $(foreach pkg, org/rocksdb/util org/rocksdb, $(MAIN_SRC)/$(pkg)/*.java)
+SOURCES = $(wildcard $(CORE_SOURCES) $(PLUGIN_SOURCES))
+PLUGIN_TEST_SOURCES = $(foreach root, $(ROCKSDB_PLUGIN_JAVA_ROOTS), $(foreach pkg, org/rocksdb/test org/rocksdb/util org/rocksdb, $(root)/$(TEST_SRC)/$(pkg)/*.java))
+CORE_TEST_SOURCES = $(foreach pkg, org/rocksdb/test org/rocksdb/util org/rocksdb, $(TEST_SRC)/$(pkg)/*.java)
+TEST_SOURCES = $(wildcard $(CORE_TEST_SOURCES) $(PLUGIN_TEST_SOURCES))
+
+# Configure the plugin tests and java classes
+ROCKSDB_PLUGIN_NATIVE_JAVA_CLASSES = $(foreach plugin, $(ROCKSDB_PLUGINS), $(foreach class, $($(plugin)_NATIVE_JAVA_CLASSES), $(class)))
+NATIVE_JAVA_CLASSES = $(NATIVE_JAVA_CLASSES) $(ROCKSDB_PLUGIN_NATIVE_JAVA_CLASSES)
+ROCKSDB_PLUGIN_JAVA_TESTS = $(foreach plugin, $(ROCKSDB_PLUGINS), $(foreach testclass, $($(plugin)_JAVA_TESTS), $(testclass)))
+ALL_JAVA_TESTS = $(JAVA_TESTS) $(ROCKSDB_PLUGIN_JAVA_TESTS)
+
 # When debugging add -Xcheck:jni to the java args
 ifneq ($(DEBUG_LEVEL),0)
 	JAVA_ARGS += -ea -Xcheck:jni
@@ -312,9 +332,7 @@ javalib: java java_test javadocs
 
 java: java-version
 	$(AM_V_GEN)mkdir -p $(MAIN_CLASSES)
-	$(AM_V_at)$(JAVAC_CMD) $(JAVAC_ARGS) -h $(NATIVE_INCLUDE) -d $(MAIN_CLASSES)\
-		$(MAIN_SRC)/org/rocksdb/util/*.java\
-		$(MAIN_SRC)/org/rocksdb/*.java
+	$(AM_V_at) $(JAVAC_CMD) $(JAVAC_ARGS) -h $(NATIVE_INCLUDE) -d $(MAIN_CLASSES) $(SOURCES)
 	$(AM_V_at)@cp ../HISTORY.md ./HISTORY-CPP.md
 	$(AM_V_at)@rm -f ./HISTORY-CPP.md
 
@@ -416,14 +434,15 @@ resolve_test_deps: $(JAVA_JUNIT_JAR_PATH) $(JAVA_HAMCREST_JAR_PATH) $(JAVA_MOCKI
 java_test: java resolve_test_deps
 	$(AM_V_GEN)mkdir -p $(TEST_CLASSES)
 	$(AM_V_at) $(JAVAC_CMD) $(JAVAC_ARGS) -cp $(MAIN_CLASSES):$(JAVA_TESTCLASSPATH) -h $(NATIVE_INCLUDE) -d $(TEST_CLASSES)\
-		$(TEST_SRC)/org/rocksdb/test/*.java\
-		$(TEST_SRC)/org/rocksdb/util/*.java\
-		$(TEST_SRC)/org/rocksdb/*.java
+		$(TEST_SOURCES)
 
 test: java java_test run_test
 
 run_test:
-	$(JAVA_CMD) $(JAVA_ARGS) -Djava.library.path=target -cp "$(MAIN_CLASSES):$(TEST_CLASSES):$(JAVA_TESTCLASSPATH):target/*" org.rocksdb.test.RocksJunitRunner $(JAVA_TESTS)
+	$(JAVA_CMD) $(JAVA_ARGS) -Djava.library.path=target -cp "$(MAIN_CLASSES):$(TEST_CLASSES):$(JAVA_TESTCLASSPATH):target/*" org.rocksdb.test.RocksJunitRunner $(ALL_JAVA_TESTS)
+
+run_plugin_test:
+	$(JAVA_CMD) $(JAVA_ARGS) -Djava.library.path=target -cp "$(MAIN_CLASSES):$(TEST_CLASSES):$(JAVA_TESTCLASSPATH):target/*" org.rocksdb.test.RocksJunitRunner $(ROCKSDB_PLUGIN_JAVA_TESTS)
 
 db_bench: java
 	$(AM_V_GEN)mkdir -p $(BENCHMARK_MAIN_CLASSES)