Add tests for Maven wrapper

java/integration-tests-lib/maven_wrapper_test_utils.py

@@ -0,0 +1,12 @@
+import sys
+import os.path
+
+def check_maven_wrapper_exists(expected_version):
+  if not os.path.exists(".mvn/wrapper/maven-wrapper.jar"):
+    print("Maven wrapper jar file expected but not found", file = sys.stderr)
+    sys.exit(1)
+  with open(".mvn/wrapper/maven-wrapper.properties", "r") as f:
+    content = f.read()
+    if ("apache-maven-%s-" % expected_version) not in content:
+      print("Expected Maven wrapper to fetch version %s, but actual properties file said:\n\n%s" % (expected_version, content), file = sys.stderr)
+      sys.exit(1)