java_gen: clean filename handling
diff --git a/Makefile b/Makefile
index 556b44e..dceb3e6 100644
--- a/Makefile
+++ b/Makefile
@@ -68,9 +68,9 @@
 
 java: .loxi_ts.java
 
-.loxi_ts.java: ${LOXI_JAVA_FILES} ${LOXI_TEMPLATE_FILES} ${INPUT_FILES}
+.loxi_ts.java: ${LOXI_PY_FILES} ${LOXI_TEMPLATE_FILES} ${INPUT_FILES}
 	./loxigen.py --install-dir=${LOXI_OUTPUT_DIR} --lang=java
-	cd loxi_output/openflowj; mvn package
+	cd ${LOXI_OUTPUT_DIR}/openflowj; mvn package
 	touch $@