Handles missing classes.jar in aar_import gracefully, by creating an empty jar file instead of crashing Bazel.
--
MOS_MIGRATED_REVID=135405636
diff --git a/tools/zip/embedded_jar_extractor.py b/tools/zip/embedded_jar_extractor.py
new file mode 100644
index 0000000..1111b29
--- /dev/null
+++ b/tools/zip/embedded_jar_extractor.py
@@ -0,0 +1,53 @@
+# Copyright 2016 The Bazel Authors. All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""A tool for extracting a jar file from an archive and failing gracefully.
+
+If the jar file is present within the archive, it is extracted into the output
+directory. If not, an empty jar is created in the output directory.
+"""
+
+import os
+import sys
+import zipfile
+
+from third_party.py import gflags
+
+FLAGS = gflags.FLAGS
+
+gflags.DEFINE_string("input_archive", None, "Input archive")
+gflags.MarkFlagAsRequired("input_archive")
+gflags.DEFINE_string("filename", None, "Filename of JAR to extract")
+gflags.MarkFlagAsRequired("filename")
+gflags.DEFINE_string("output_dir", None, "Output directory")
+gflags.MarkFlagAsRequired("output_dir")
+
+
+def ExtractEmbeddedJar(input_archive, filename, output_dir):
+ with zipfile.ZipFile(input_archive, "r") as archive:
+ if filename in archive.namelist():
+ archive.extract(filename, output_dir)
+ else:
+ with zipfile.ZipFile(os.path.join(output_dir, filename), "w") as jar:
+ # All jar files must contain META-INF/MANIFEST.MF.
+ jar.writestr("META-INF/MANIFEST.MF", ("Manifest-Version: 1.0\n"
+ "Created-By: Bazel\n"))
+
+
+def main():
+ ExtractEmbeddedJar(FLAGS.input_archive, FLAGS.filename, FLAGS.output_dir)
+
+if __name__ == "__main__":
+ FLAGS(sys.argv)
+ main()
