@contextmanager
  def create_jar_builder(self, jar):
    builder = self.JarBuilder(self.context, jar)
    yield builder
    builder.commit_manifest(jar)
Creates a ``JarTask.JarBuilder`` ready for use.
dataset/ETHPy150Open pantsbuild/pants/src/python/pants/backend/jvm/tasks/jar_task.py/JarBuilderTask.create_jar_builder