@Override
    public String toString() {
      StringBuilder sb = new StringBuilder("echo_args(");
      boolean first = true;

      sb.append("message:");
      if (this.message == null) {
        sb.append("null");
      } else {
        sb.append(this.message);
      }
      first = false;
      sb.append(")");
      return sb.toString();
    }
Returns true if field corresponding to fieldID is set (has been assigned a value) and false otherwise
agent-module/agent-testweb/thrift-plugin-testweb/src/main/java/com/pinpoint/test/plugin/dto/EchoService.java