diff --git a/core/java.mk b/core/java.mk
new file mode 100644
index 0000000..a391ccb
--- /dev/null
+++ b/core/java.mk
@@ -0,0 +1,115 @@
+# Requires:
+# LOCAL_MODULE_SUFFIX
+# LOCAL_MODULE_CLASS
+# all_res_assets
+
+# Make sure there's something to build.
+# It's possible to build a package that doesn't contain any classes.
+ifeq (,$(strip $(LOCAL_SRC_FILES)$(all_res_assets)))
+$(error $(LOCAL_PATH): Target java module does not define any source or resource files)
+endif
+
+LOCAL_NO_STANDARD_LIBRARIES:=$(strip $(LOCAL_NO_STANDARD_LIBRARIES))
+LOCAL_SDK_VERSION:=$(strip $(LOCAL_SDK_VERSION))
+
+ifneq ($(LOCAL_SDK_VERSION),)
+  ifeq ($(LOCAL_NO_STANDARD_LIBRARIES),true)
+    $(error $(LOCAL_PATH): Must not define both LOCAL_NO_STANDARD_LIBRARIES and LOCAL_SDK_VERSION)
+  else
+    ifeq ($(strip $(filter $(LOCAL_SDK_VERSION),$(TARGET_AVAILABLE_SDK_VERSIONS))),)
+      $(error $(LOCAL_PATH): Invalid LOCAL_SDK_VERSION '$(LOCAL_SDK_VERSION)' \
+             Choices are: $(TARGET_AVAILABLE_SDK_VERSIONS))
+    else
+      LOCAL_JAVA_LIBRARIES := android_stubs_$(LOCAL_SDK_VERSION) $(LOCAL_JAVA_LIBRARIES) 
+    endif
+  endif
+else
+  ifneq ($(LOCAL_NO_STANDARD_LIBRARIES),true)
+    LOCAL_JAVA_LIBRARIES := core ext framework $(LOCAL_JAVA_LIBRARIES)
+  endif
+endif
+
+LOCAL_BUILT_MODULE_STEM := $(strip $(LOCAL_BUILT_MODULE_STEM))
+ifeq ($(LOCAL_BUILT_MODULE_STEM),)
+$(error $(LOCAL_PATH): Target java template must define LOCAL_BUILT_MODULE_STEM)
+endif
+ifeq ($(LOCAL_BUILT_MODULE_STEM),classes.jar)
+$(error LOCAL_BUILT_MODULE_STEM may not be "classes.jar")
+endif
+
+#######################################
+include $(BUILD_SYSTEM)/base_rules.mk
+#######################################
+
+# We use intermediates.COMMON because the classes.jar/.dex files will be
+# common even if LOCAL_BUILT_MODULE isn't.
+#
+# Override some target variables that base_rules set up for us.
+$(LOCAL_INTERMEDIATE_TARGETS): \
+	PRIVATE_CLASS_INTERMEDIATES_DIR := $(intermediates.COMMON)/classes
+$(LOCAL_INTERMEDIATE_TARGETS): \
+	PRIVATE_SOURCE_INTERMEDIATES_DIR := $(intermediates.COMMON)/src
+
+# Since we're using intermediates.COMMON, make sure that it gets cleaned
+# properly.
+$(cleantarget): PRIVATE_CLEAN_FILES += $(intermediates.COMMON)
+
+# If the module includes java code (i.e., it's not framework-res), compile it.
+full_classes_jar :=
+built_dex :=
+ifneq (,$(strip $(all_java_sources)))
+
+# If LOCAL_BUILT_MODULE_STEM wasn't overridden by our caller,
+# full_classes_jar will be the same module as LOCAL_BUILT_MODULE.
+# Otherwise, the caller will define it as a prerequisite of
+# LOCAL_BUILT_MODULE, so it will inherit the necessary PRIVATE_*
+# variable definitions.
+#
+# This intentionally depends on java_sources, not all_java_sources.
+# Deps for generated source files must be handled separately,
+# via deps on the target that generates the sources.
+full_classes_jar := $(intermediates.COMMON)/classes.jar
+$(full_classes_jar): $(java_sources) $(full_java_lib_deps)
+	$(transform-java-to-classes.jar)
+
+built_dex := $(intermediates.COMMON)/classes.dex
+
+# Override PRIVATE_INTERMEDIATES_DIR so that install-dex-debug
+# will work even when intermediates != intermediates.COMMON.
+$(built_dex): PRIVATE_INTERMEDIATES_DIR := $(intermediates.COMMON)
+$(built_dex): PRIVATE_DX_FLAGS := $(LOCAL_DX_FLAGS)
+$(built_dex): $(full_classes_jar) $(DX)
+	$(transform-classes.jar-to-dex)
+ifneq ($(GENERATE_DEX_DEBUG),)
+	$(install-dex-debug)
+endif
+
+findbugs_xml := $(intermediates.COMMON)/findbugs.xml
+$(findbugs_xml) : PRIVATE_JAR_FILE := $(full_classes_jar)
+$(findbugs_xml) : PRIVATE_AUXCLASSPATH := $(addprefix -auxclasspath ,$(strip \
+								$(call normalize-path-list,$(filter %.jar,\
+										$(full_java_libs)))))
+# We can't depend directly on full_classes_jar because the PRIVATE_
+# vars won't be set up correctly.
+$(findbugs_xml) : $(LOCAL_BUILT_MODULE)
+	@echo Findbugs: $@
+	$(hide) $(FINDBUGS) -textui -effort:min -xml:withMessages \
+		$(PRIVATE_AUXCLASSPATH) \
+		$(PRIVATE_JAR_FILE) \
+		> $@
+
+ALL_FINDBUGS_FILES += $(findbugs_xml)
+
+findbugs_html := $(PRODUCT_OUT)/findbugs/$(LOCAL_MODULE).html
+$(findbugs_html) : PRIVATE_XML_FILE := $(findbugs_xml)
+$(LOCAL_MODULE)-findbugs : $(findbugs_html)
+$(findbugs_html) : $(findbugs_xml)
+	@mkdir -p $(dir $@)
+	@echo UnionBugs: $@
+	$(hide) prebuilt/common/findbugs/bin/unionBugs $(PRIVATE_XML_FILE) \
+	| prebuilt/common/findbugs/bin/convertXmlToText -html:fancy.xsl \
+	> $@
+
+$(LOCAL_MODULE)-findbugs : $(findbugs_html)
+
+endif