class Jars::Installer

def do_install(vendor_dir, write_require_file)
  if !spec.require_paths.include?(vendor_dir) && vendor_dir
    raise "vendor dir #{vendor_dir} not in require_paths of gemspec #{spec.require_paths}"
  end
  target_dir = File.join(@mvn.basedir, vendor_dir || spec.require_path)
  jars_file = File.join(target_dir, "#{spec.name}_jars.rb")
  # write out new jars_file it write_require_file is true or
  # check timestamps:
  # do not generate file if specfile is older then the generated file
  if !write_require_file &&
     File.exist?(jars_file) &&
     File.mtime(@mvn.specfile) < File.mtime(jars_file)
    # leave jars_file as is
    jars_file = nil
  end
  deps = install_dependencies
  self.class.write_require_jars(deps, jars_file)
  self.class.vendor_jars(deps, target_dir) if vendor_dir
end