--- a/make/RunTestsPrebuiltSpec.gmk	Thu Oct 11 14:44:23 2018 -0700
+++ b/make/RunTestsPrebuiltSpec.gmk	Fri Oct 12 17:45:44 2018 -0700
@@ -124,7 +124,7 @@
 JMOD := $(FIXPATH) $(JMOD_CMD)
 JARSIGNER := $(FIXPATH) $(JARSIGNER_CMD)
 
-BUILD_JAVA := $(JAVA)
+BUILD_JAVA := $(JDK_IMAGE_DIR)/bin/JAVA
 ################################################################################
 # Some common tools. Assume most common name and no path.
 AWK := awk