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java Equals方法不能很好地处理Throwable

我有一些外部提供的回调要运行。由于它们可以包含任何内容,我更愿意冒险捕捉它们,从而从任何可恢复的错误中恢复

回调执行的某些阶段允许抛出错误,除非错误在一行中重复两次。在这种情况下,它们被标记为无效,除非用户手动启动,否则无法再运行

这就是处理以下问题的方法:

  /**
   * Sets whether the bot is disabled due to error or not. If error has occured during 
   * getWindow, the bot will be disabled immediatelly. If the error occured during canRun() or run()
   * the bot will only be disabled if the error is repetitive.
   * @param error error that occured
   * @param phase phase of execution in which the error occured
   * @return true if this error is not significant enough to cancel this bot
   */
  public boolean continueOnError(Throwable error, ExecutionPhase phase) {
    System.err.println("Error "+error+" caught in robot "+this.getClass().getName());
    System.err.println("Last: "+lastError+((error.equals(lastError)?" which is the same as last":" which is defferent than last")));
    if(phase == ExecutionPhase.GET_WINDOW || (error.equals(lastError) && phase==errorPhase)) {
      //Remember last
      setLastError(error, phase);
      //If robot state listener is listening, inform it about this event
      if(listener!=null)
        listener.disabledByError(error);
      //Disable the robot - on attempt to run, it will throw RobotDisabledException
      return !(errorDisabled = true);
    }
    //Rememeber last
    setLastError(error, phase);
    //The robot can remain running, but next same error will turn it down
    return true;
  }

我知道这是一种原始的方法,但我需要从某个地方开始。这段代码的问题是Throwable上的equals方法总是返回false。请参见此方法生成的输出:

Error java.lang.Error: TEST ERROR caught in robot cz.autoclient.robots.LaunchBot
Last: java.lang.Error: TEST ERROR which is defferent than last
Error java.lang.Error: TEST ERROR caught in robot cz.autoclient.robots.LaunchBot
Last: java.lang.Error: TEST ERROR which is defferent than last
Error java.lang.Error: TEST ERROR caught in robot cz.autoclient.robots.LaunchBot
Last: java.lang.Error: TEST ERROR which is defferent than last
Error java.lang.Error: TEST ERROR caught in robot cz.autoclient.robots.LaunchBot
Last: java.lang.Error: TEST ERROR which is defferent than last

为什么会这样


共 (1) 个答案

  1. # 1 楼答案

    Throwable重写equals(),问题在于ErrorLastError实例可能是两个具有相同值的不同Throwable实例