diff --git a/core/clear_vars.mk b/core/clear_vars.mk
index c38059c..b5bb963 100644
--- a/core/clear_vars.mk
+++ b/core/clear_vars.mk
@@ -120,6 +120,7 @@
 LOCAL_JAR_PROCESSOR:=
 LOCAL_JAR_PROCESSOR_ARGS:=
 LOCAL_JAVACFLAGS:=
+LOCAL_JAVAC_SHARD_SIZE:=
 LOCAL_JAVA_LANGUAGE_VERSION:=
 LOCAL_JAVA_LAYERS_FILE:=
 LOCAL_JAVA_LIBRARIES:=
diff --git a/core/definitions.mk b/core/definitions.mk
index cb0a6bb..1f9891e 100644
--- a/core/definitions.mk
+++ b/core/definitions.mk
@@ -2205,6 +2205,17 @@
     @<(find $(1) -type f | sort | $(JAR_ARGS) $(1); echo "-C $(EMPTY_DIRECTORY) .")
 endef
 
+# append additional Java sources(resources/Proto sources, and etc) to $(1).
+define fetch-additional-java-source
+$(hide) if [ -d "$(PRIVATE_SOURCE_INTERMEDIATES_DIR)" ]; then \
+    find $(PRIVATE_SOURCE_INTERMEDIATES_DIR) -name '*.java' -and -not -name '.*' >> $(1); \
+fi
+$(if $(PRIVATE_HAS_PROTO_SOURCES), \
+    $(hide) find $(PRIVATE_PROTO_SOURCE_INTERMEDIATES_DIR) -name '*.java' -and -not -name '.*' >> $(1))
+$(if $(PRIVATE_HAS_RS_SOURCES), \
+    $(hide) find $(PRIVATE_RS_SOURCE_INTERMEDIATES_DIR) -name '*.java' -and -not -name '.*' >> $(1))
+endef
+
 # Some historical notes:
 # - below we write the list of java files to java-source-list to avoid argument
 #   list length problems with Cygwin
@@ -2214,16 +2225,20 @@
 @echo "$($(PRIVATE_PREFIX)DISPLAY) Java source list: $(PRIVATE_MODULE)"
 $(hide) rm -f $@
 $(call dump-words-to-file,$(sort $(PRIVATE_JAVA_SOURCES)),$@.tmp)
-$(hide) if [ -d "$(PRIVATE_SOURCE_INTERMEDIATES_DIR)" ]; then \
-    find $(PRIVATE_SOURCE_INTERMEDIATES_DIR) -name '*.java' -and -not -name '.*' >> $@.tmp; \
-fi
-$(if $(PRIVATE_HAS_PROTO_SOURCES), \
-    $(hide) find $(PRIVATE_PROTO_SOURCE_INTERMEDIATES_DIR) -name '*.java' -and -not -name '.*' >> $@.tmp)
-$(if $(PRIVATE_HAS_RS_SOURCES), \
-    $(hide) find $(PRIVATE_RS_SOURCE_INTERMEDIATES_DIR) -name '*.java' -and -not -name '.*' >> $@.tmp)
+$(call fetch-additional-java-source,$@.tmp)
 $(hide) tr ' ' '\n' < $@.tmp | $(NORMALIZE_PATH) | sort -u > $@
 endef
 
+# $(1): sharding number.
+# $(2): Java source files paths.
+define save-sharded-java-source-list
+$(java_source_list_file).shard.$(1): $(2) $$(NORMALIZE_PATH)
+	@echo "shard java source list: $$@"
+	rm -f $$@
+	$$(call dump-words-to-file,$(2),$$@.tmp)
+	$(hide) tr ' ' '\n' < $$@.tmp | $$(NORMALIZE_PATH) | sort -u > $$@
+endef
+
 # Common definition to invoke javac on the host and target.
 #
 # $(1): javac
@@ -2265,9 +2280,33 @@
 $(if $(PRIVATE_EXTRA_JAR_ARGS),$(call add-java-resources-to,$@))
 endef
 
-define transform-java-to-classes.jar
-@echo "$($(PRIVATE_PREFIX)DISPLAY) Java: $(PRIVATE_MODULE) ($(PRIVATE_CLASS_INTERMEDIATES_DIR))"
-$(call compile-java,$(TARGET_JAVAC),$(PRIVATE_ALL_JAVA_HEADER_LIBRARIES))
+# $(1): Javac output jar name.
+# $(2): Java source list file.
+# $(3): Java header libs.
+# $(4): Javac sharding number.
+# $(5): Javac sources deps (the arg may neeed $$ in case of containing '#')
+define create-classes-full-debug.jar
+$(1): PRIVATE_JAVACFLAGS := $$(LOCAL_JAVACFLAGS) $$(annotation_processor_flags)
+$(1): PRIVATE_JAR_EXCLUDE_FILES := $$(LOCAL_JAR_EXCLUDE_FILES)
+$(1): PRIVATE_JAR_PACKAGES := $$(LOCAL_JAR_PACKAGES)
+$(1): PRIVATE_JAR_EXCLUDE_PACKAGES := $$(LOCAL_JAR_EXCLUDE_PACKAGES)
+$(1): PRIVATE_DONT_DELETE_JAR_META_INF := $$(LOCAL_DONT_DELETE_JAR_META_INF)
+$(1): PRIVATE_JAVA_SOURCE_LIST := $(2)
+$(1): PRIVATE_ALL_JAVA_HEADER_LIBRARIES := $(3)
+$(1): PRIVATE_CLASS_INTERMEDIATES_DIR := $(intermediates.COMMON)/classes$(4)
+$(1): PRIVATE_ANNO_INTERMEDIATES_DIR := $(intermediates.COMMON)/anno$(4)
+$(1): \
+    $(2) \
+    $(3) \
+    $(5) \
+    $$(full_java_bootclasspath_libs) \
+    $$(layers_file) \
+    $$(annotation_processor_deps) \
+    $$(NORMALIZE_PATH) \
+    $$(JAR_ARGS) \
+    | $$(SOONG_JAVAC_WRAPPER)
+	@echo "Target Java: $$@ ($$(PRIVATE_CLASS_INTERMEDIATES_DIR))"
+	$$(call compile-java,$$(TARGET_JAVAC),$$(PRIVATE_ALL_JAVA_HEADER_LIBRARIES))
 endef
 
 define transform-java-to-header.jar
diff --git a/core/java.mk b/core/java.mk
index 5eddb0e..cf49994 100644
--- a/core/java.mk
+++ b/core/java.mk
@@ -352,7 +352,36 @@
 ##########################################
 java_sources := $(addprefix $(LOCAL_PATH)/, $(filter %.java,$(LOCAL_SRC_FILES))) $(aidl_java_sources) $(logtags_java_sources) \
                 $(filter %.java,$(LOCAL_GENERATED_SOURCES))
-all_java_sources := $(java_sources) $(addprefix $(TARGET_OUT_COMMON_INTERMEDIATES)/, $(filter %.java,$(LOCAL_INTERMEDIATE_SOURCES)))
+java_intermediate_sources := $(addprefix $(TARGET_OUT_COMMON_INTERMEDIATES)/, $(filter %.java,$(LOCAL_INTERMEDIATE_SOURCES)))
+all_java_sources := $(java_sources) $(java_intermediate_sources)
+
+enable_sharding :=
+ifneq ($(TURBINE_ENABLED),false)
+ifneq ($(LOCAL_JAVAC_SHARD_SIZE),)
+ifneq ($(LOCAL_JAR_PROCESSOR),)
+$(call pretty-error,Cannot set both LOCAL_JAVAC_SHARD_SIZE and LOCAL_JAR_PROCESSOR!)
+endif # LOCAL_JAR_PROCESSOR is not empty
+enable_sharding := true
+
+num_shards := $(call int_divide,$(words $(java_sources)),$(LOCAL_JAVAC_SHARD_SIZE))
+ifneq ($(words $(java_sources)),$(call int_multiply,$(LOCAL_JAVAC_SHARD_SIZE),$(num_shards)))
+# increment number of shards by 1.
+num_shards := $(call int_plus,$(num_shards),1)
+endif
+
+shard_idx_list := $(call int_range_list,1,$(num_shards))
+sharded_java_source_list_files += $(foreach x,$(shard_idx_list),$(java_source_list_file).shard.$(x))
+sharded_jar_list += $(foreach x,$(shard_idx_list),$(full_classes_compiled_jar).shard.$(x))
+
+# always put dynamically-located .java files (generated by Proto/resource, etc) in a new final shard.
+# increment number of shards by 1.
+num_shards := $(call int_plus,$(num_shards),1)
+sharded_java_source_list_files += $(java_source_list_file).shard.$(num_shards)
+sharded_jar_list += $(full_classes_compiled_jar).shard.$(num_shards)
+LOCAL_INTERMEDIATE_TARGETS += $(sharded_java_source_list_files)
+LOCAL_INTERMEDIATE_TARGETS += $(sharded_jar_list)
+endif # LOCAL_JAVAC_SHARD_SIZE is not empty
+endif # TURBINE_ENABLED != false
 
 include $(BUILD_SYSTEM)/java_common.mk
 
@@ -419,23 +448,47 @@
 $(java_source_list_file): $(java_sources_deps)
 	$(write-java-source-list)
 
-$(full_classes_compiled_jar): PRIVATE_JAVACFLAGS := $(LOCAL_JAVACFLAGS) $(annotation_processor_flags)
-$(full_classes_compiled_jar): PRIVATE_JAR_EXCLUDE_FILES := $(LOCAL_JAR_EXCLUDE_FILES)
-$(full_classes_compiled_jar): PRIVATE_JAR_PACKAGES := $(LOCAL_JAR_PACKAGES)
-$(full_classes_compiled_jar): PRIVATE_JAR_EXCLUDE_PACKAGES := $(LOCAL_JAR_EXCLUDE_PACKAGES)
-$(full_classes_compiled_jar): PRIVATE_DONT_DELETE_JAR_META_INF := $(LOCAL_DONT_DELETE_JAR_META_INF)
-$(full_classes_compiled_jar): PRIVATE_JAVA_SOURCE_LIST := $(java_source_list_file)
-$(full_classes_compiled_jar): \
-    $(java_source_list_file) \
-    $(java_sources_deps) \
-    $(full_java_header_libs) \
-    $(full_java_bootclasspath_libs) \
-    $(layers_file) \
-    $(annotation_processor_deps) \
-    $(NORMALIZE_PATH) \
-    $(JAR_ARGS) \
-    | $(SOONG_JAVAC_WRAPPER)
-	$(transform-java-to-classes.jar)
+ifdef enable_sharding
+$(foreach x,$(shard_idx_list),\
+  $(eval $(call save-sharded-java-source-list,$(x),\
+    $(wordlist $(call int_plus,1,$(call int_multiply,$(LOCAL_JAVAC_SHARD_SIZE),$(call int_subtract,$(x),1))),\
+      $(call int_multiply,$(LOCAL_JAVAC_SHARD_SIZE),$(x)),$(sort $(java_sources))))))
+
+# always put dynamically-located .java files (generated by Proto/resource, etc) in a new final shard.
+$(java_source_list_file).shard.$(num_shards): PRIVATE_JAVA_INTERMEDIATE_SOURCES := $(java_intermediate_sources)
+$(java_source_list_file).shard.$(num_shards): $(java_resource_sources) \
+    $(RenderScript_file_stamp) \
+    $(proto_java_sources_file_stamp) \
+    $(LOCAL_ADDITIONAL_DEPENDENCIES) \
+    $(NORMALIZE_PATH)
+	$(hide) rm -f $@
+	$(call dump-words-to-file,$(PRIVATE_JAVA_INTERMEDIATE_SOURCES),$@.tmp)
+	$(call fetch-additional-java-source,$@.tmp)
+	$(hide) tr ' ' '\n' < $@.tmp | $(NORMALIZE_PATH) | sort -u > $@
+
+# Javac sharding with header libs including its own header jar as one of dependency.
+$(foreach x,$(shard_idx_list),\
+  $(eval $(call create-classes-full-debug.jar,$(full_classes_compiled_jar).shard.$(x),\
+    $(java_source_list_file).shard.$(x),\
+      $(full_java_header_libs) $(full_classes_header_jar),$(x),\
+        $(wordlist $(call int_plus,1,$(call int_multiply,$(LOCAL_JAVAC_SHARD_SIZE),$(call int_subtract,$(x),1))),\
+          $(call int_multiply,$(LOCAL_JAVAC_SHARD_SIZE),$(x)),$(sort $(java_sources))))))
+
+# Javac sharding for last shard with additional Java dependencies.
+$(eval $(call create-classes-full-debug.jar,$(full_classes_compiled_jar).shard.$(num_shards),\
+  $(java_source_list_file).shard.$(num_shards),$(full_java_header_libs) $(full_classes_header_jar),$(strip \
+    $(num_shards)),$$(java_resource_sources) $$(RenderScript_file_stamp) \
+      $$(proto_java_sources_file_stamp) $$(LOCAL_ADDITIONAL_DEPENDENCIES)))
+
+$(full_classes_compiled_jar): PRIVATE_SHARDED_JAR_LIST := $(sharded_jar_list)
+$(full_classes_compiled_jar): $(sharded_jar_list) | $(MERGE_ZIPS)
+	$(MERGE_ZIPS) -j $@ $(PRIVATE_SHARDED_JAR_LIST)
+else
+# we can't use single $ for java_sources_deps since it may contain hash '#' sign.
+$(eval $(call create-classes-full-debug.jar,$(full_classes_compiled_jar),\
+  $(java_source_list_file),$(full_java_header_libs),,$$(java_sources_deps)))
+
+endif # ifdef enable_sharding
 
 ifneq ($(TURBINE_ENABLED),false)
 
diff --git a/core/math.mk b/core/math.mk
index 047d046..57cb681 100644
--- a/core/math.mk
+++ b/core/math.mk
@@ -42,6 +42,11 @@
 $(if $(call math_is_number,$(1)),,$(error Only positive integers <= 100 are supported (not $(1))))
 endef
 
+# return a list containing integers ranging from [$(1),$(2)]
+define int_range_list
+$(call _math_check_valid,$(1))$(call _math_check_valid,$(2))$(wordlist $(1),$(2),$(__MATH_NUMBERS))
+endef
+
 #$(call _math_check_valid,0)
 #$(call _math_check_valid,1)
 #$(call _math_check_valid,100)
@@ -75,3 +80,60 @@
 define inc_and_print
 $(strip $(eval $(1) := $($(1)) .)$(words $($(1))))
 endef
+
+_INT_LIMIT_WORDS := $(foreach a,x x,$(foreach b,x x x x x x x x x x x x x x x x,\
+  $(foreach c,x x x x x x x x x x x x x x x x,x x x x x x x x x x x x x x x x)))
+
+define _int_encode
+$(if $(filter $(words x $(_INT_LIMIT_WORDS)),$(words $(wordlist 1,$(1),x $(_INT_LIMIT_WORDS)))),\
+  $(call pretty-error,integer greater than $(words $(_INT_LIMIT_WORDS)) is not supported!),\
+    $(wordlist 1,$(1),$(_INT_LIMIT_WORDS)))
+endef
+
+# _int_max returns the maximum of the two arguments
+# input: two (x) lists; output: one (x) list
+# integer cannot be passed in directly. It has to be converted using _int_encode.
+define _int_max
+$(subst xx,x,$(join $(1),$(2)))
+endef
+
+# first argument is greater than second argument
+# output: non-empty if true
+# integer cannot be passed in directly. It has to be converted using _int_encode.
+define _int_greater-than
+$(filter-out $(words $(2)),$(words $(call _int_max,$(1),$(2))))
+endef
+
+# first argument equals to second argument
+# output: non-empty if true
+# integer cannot be passed in directly. It has to be converted using _int_encode.
+define _int_equal
+$(filter $(words $(1)),$(words $(2)))
+endef
+
+# first argument is greater than or equal to second argument
+# output: non-empty if true
+# integer cannot be passed in directly. It has to be converted using _int_encode.
+define _int_greater-or-equal
+$(call _int_greater-than,$(1),$(2))$(call _int_equal,$(1),$(2))
+endef
+
+define int_plus
+$(words $(call _int_encode,$(1)) $(call _int_encode,$(2)))
+endef
+
+define int_subtract
+$(if $(call _int_greater-or-equal,$(call _int_encode,$(1)),$(call _int_encode,$(2))),\
+  $(words $(filter-out xx,$(join $(call _int_encode,$(1)),$(call _int_encode,$(2))))),\
+    $(call pretty-error,$(1) subtract underflow $(2)))
+endef
+
+define int_multiply
+$(words $(foreach a,$(call _int_encode,$(1)),$(call _int_encode,$(2))))
+endef
+
+define int_divide
+$(if $(filter 0,$(2)),$(call pretty-error,division by zero is not allowed!),$(strip \
+  $(if $(call _int_greater-or-equal,$(call _int_encode,$(1)),$(call _int_encode,$(2))), \
+    $(call int_plus,$(call int_divide,$(call int_subtract,$(1),$(2)),$(2)),1),0)))
+endef
diff --git a/core/package_internal.mk b/core/package_internal.mk
index 5a1ef05..01e2463 100644
--- a/core/package_internal.mk
+++ b/core/package_internal.mk
@@ -333,6 +333,7 @@
 # Make sure the data-binding process happens before javac and generation of R.java.
 $(R_file_stamp): $(data_binding_stamp)
 $(java_source_list_file): $(data_binding_stamp)
+$(foreach x,$(sharded_java_source_list_files),$(eval $(x): $(data_binding_stamp)))
 $(full_classes_compiled_jar): $(data_binding_stamp)
 endif  # LOCAL_DATA_BINDING
 
@@ -426,6 +427,7 @@
 # The R.java file must exist by the time the java source
 # list is generated
 $(java_source_list_file): $(R_file_stamp)
+$(foreach x,$(sharded_java_source_list_files),$(eval $(x): $(R_file_stamp)))
 
 endif  # need_compile_res
 
diff --git a/core/static_java_library.mk b/core/static_java_library.mk
index ca3b071..c402dce 100644
--- a/core/static_java_library.mk
+++ b/core/static_java_library.mk
@@ -168,6 +168,7 @@
 
 $(LOCAL_BUILT_MODULE): $(R_file_stamp)
 $(java_source_list_file): $(R_file_stamp)
+$(foreach x,$(sharded_java_source_list_files),$(eval $(x): $(R_file_stamp)))
 $(full_classes_compiled_jar): $(R_file_stamp)
 $(full_classes_turbine_jar): $(R_file_stamp)