diff --git a/core/java_common.mk b/core/java_common.mk index ba475fa33a..35e2923a9f 100644 --- a/core/java_common.mk +++ b/core/java_common.mk @@ -3,8 +3,24 @@ ########################################################### ## Java version ########################################################### +# Use the LOCAL_JAVA_LANGUAGE_VERSION if it is set, otherwise +# use one based on the LOCAL_SDK_VERSION. If it is < 24 +# pass "1.7" to the tools, if it is unset, >= 24 or "current" +# pass "1.8". +# +# The LOCAL_SDK_VERSION behavior is to ensure that, by default, +# code that is expected to run on older releases of Android +# does not use any 1.8 language features that are not supported +# on earlier runtimes (like default / static interface methods). +# Modules can override this logic by specifying +# LOCAL_JAVA_LANGUAGE_VERSION explicitly. ifeq (,$(LOCAL_JAVA_LANGUAGE_VERSION)) - LOCAL_JAVA_LANGUAGE_VERSION := 1.8 + private_sdk_versions_without_any_java_18_support := 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 + ifneq (,$(filter $(LOCAL_SDK_VERSION), $(private_sdk_versions_without_any_java_18_support))) + LOCAL_JAVA_LANGUAGE_VERSION := 1.7 + else + LOCAL_JAVA_LANGUAGE_VERSION := 1.8 + endif endif LOCAL_JAVACFLAGS += -source $(LOCAL_JAVA_LANGUAGE_VERSION) -target $(LOCAL_JAVA_LANGUAGE_VERSION)