Java这是什么错误啊？？？？急死了！！

来源：百度知道 编辑：UC知道 时间：2024/07/03 01:29:56
运行之后出现这么多错误，是在执行鼠标动作监听器时出现的
Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
at Calculator.getResult(Calculator.java:306)
at Calculator.actionPerformed(Calculator.java:193)
at javax.swing.AbstractButton.fireActionPerformed(Unknown Source)
at javax.swing.AbstractButton$Handler.actionPerformed(Unknown Source)
at javax.swing.DefaultButtonModel.fireActionPerformed(Unknown Source)
at javax.swing.DefaultButtonModel.setPressed(Unknown Source)
at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(Unknown Source)
at java.awt.Component.processMouseEvent(Unknown Source)
at javax.swing.JComponent.processMouseEvent(Unknown Source)
at java.awt.Component.processEvent(Unknown Source)
at java.awt.Container.processEvent(Unknown Source)
at java.awt.Component.dispatchEventImpl(Unknown Source)
at java.awt.Container.dispatchEventImpl(Unknown Source)
at java.awt.Component.dispatchEven

空指针异常，检查变量或参数是不是没有初始化！或者在引用外部资源时把资源名写错了..

空指针异常：可能设置鼠标监听器时的监听对象有问题
里面某些对象应用没得到赋值
要看源代码，才能找出具体问题

空指针异常
我连代码都不知道怎么知道你怎么错了呢？

下次直接贴代码 别贴异常

空指针异常