build/protoc_java.py

#!/usr/bin/env python
# Copyright (c) 2012 The Chromium Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

"""Generate java source files from protobuf files.

Usage:
    protoc_java.py {protoc} {proto_path} {java_out} {stamp_file} {proto_files}

This is a helper file for the genproto_java action in protoc_java.gypi.

It performs the following steps:
1. Deletes all old sources (ensures deleted classes are not part of new jars).
2. Creates source directory.
3. Generates Java files using protoc.
4. Creates a new stamp file.
"""

import os
import shutil
import subprocess
import sys

def main(argv):
  if len(argv) < 5:
    usage()
    return 1

  protoc_path, proto_path, java_out, stamp_file = argv[1:5]
  proto_files = argv[5:]

  # Delete all old sources.
  if os.path.exists(java_out):
    shutil.rmtree(java_out)

  # Create source directory.
  os.makedirs(java_out)

  # Specify arguments to the generator.
  generator_args = ['optional_field_style=reftypes',
                    'store_unknown_fields=true']
  out_arg = '--javanano_out=' + ','.join(generator_args) + ':' + java_out

  # Generate Java files using protoc.
  ret = subprocess.call(
      [protoc_path, '--proto_path', proto_path, out_arg] + proto_files)

  if ret == 0:
    # Create a new stamp file.
    with file(stamp_file, 'a'):
      os.utime(stamp_file, None)

  return ret

def usage():
  print(__doc__);

if __name__ == '__main__':
  sys.exit(main(sys.argv))