diff --git a/core/combo/javac.mk b/core/combo/javac.mk
index 41ebc57..122d8bc 100644
--- a/core/combo/javac.mk
+++ b/core/combo/javac.mk
@@ -16,12 +16,17 @@
   endif
 endif
 
-ifeq ($(OVERRIDE_ANDROID_JAVA_HOME),)
-ANDROID_JAVA_HOME := prebuilts/jdk/jdk8/$(HOST_PREBUILT_TAG)
-else
-# Use this build toolchain instead of the bundled one.
-ANDROID_JAVA_HOME := $(OVERRIDE_ANDROID_JAVA_HOME)
+ifneq ($(OVERRIDE_ANDROID_JAVA_HOME),)
+  # Use this build toolchain instead of the bundled one.
+  ANDROID_JAVA_HOME := $(OVERRIDE_ANDROID_JAVA_HOME)
+else # !OVERRIDE_ANDROID_JAVA_HOME
+  ifneq ($(EXPERIMENTAL_USE_OPENJDK9),)
+    ANDROID_JAVA_HOME := prebuilts/jdk/jdk9/$(HOST_PREBUILT_TAG)
+  else
+    ANDROID_JAVA_HOME := prebuilts/jdk/jdk8/$(HOST_PREBUILT_TAG)
+  endif
 endif
+
 ANDROID_JAVA_TOOLCHAIN := $(ANDROID_JAVA_HOME)/bin
 export JAVA_HOME := $(abspath $(ANDROID_JAVA_HOME))