意思是说你现在的这个类不是抽象类(abstract)，所以你不能在这个类里重写里面的抽象方法 检查是不是拼写错了,你要写的actionPerform方法应该是actionperformed吧?
不过，上边的意思是：XX 不是抽象的，不能重载抽象方法actionPerformed 检查是不是拼写错了,你要写的actionPerform方法应该是actionperformed吧?1
@文心快码overridden method does not throw 'java.text.parseexception 文心快码 在Java编程中,当覆盖(override)一个方法时,关于异常抛出的规则是非常重要的。下面我将详细解释这些规则,并分析你提到的问题,即覆盖的方法没有抛出java.text.ParseException的可能原因,最后提供解决方案。 1. Java中方法覆盖时的异常抛出...
override fun surfaceChanged(holder: SurfaceHolder?, format: Int, width: Int, height: Int) { 可以看到第一个参数是可空参数 , 这个问号总不会是我打上去的吧 ; 这Kotlin 相关的 前后冲突的操作 , Android 官方没少干这事 ; 解决方案 : 在Kotlin 中 , 将所有的重写的函数的可空参数 , 都改为非空...
Pull requests2 Actions Security Insights Additional navigation options New issue Closed francescotarantinoopened this issueNov 8, 2016· 22 comments Closed opened this issueNov 8, 2016· 22 comments mikepenzclosed this ascompletedNov 9, 2016
（某种事物）不是抽象的，不需要抽象方法（来分析处理）。不
public void actionperformed(ActionEvent e) 方法 改为 public void actionPerformed(ActionEvent e) 方法 看
polymorphism works by creating a relationship between classes using inheritance. when a superclass defines a method, its subclasses can override that method to provide their own implementation. at runtime, the appropriate method is called based on the actual type of the object. this dynamic binding...
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