Q1: why we should initialize final field before completion of new instance? final means no changeable in java enviroment, the java compiler urges us follow the security violation. Q2: how to resolve the error above? actually, it is because factors pe…
Java allows the creation of blank finals, which are fields that are declared as final but are not given an initialization value. In all case, the blank final must be initialized before it is used, and the compilers ensures this. However, blank finals…
/** * An empty table instance to share when the table is not inflated. */ static final Entry<?,?>[] EMPTY_TABLE = {}; final 修饰的类不能被继承 final 修饰的方法不能被重写 final 修饰的变量不能被重新赋值 不能被二次赋值 The final field Test1.PERSON_LIST cannot be assigned 不能不赋值 The blank fi…
final关键字在java中是一个很重要的关键字,其实按照其字面意思理解,就可以一窥这个关键字端倪,final的本意是最终的.所谓最终的,其最重要的特征就是不能修改,由此衍生出的许多细节均应以这个特征作为基础. final可以修饰类.方法.变量.变量包括成员变量和局部变量. 1.修饰类 final修饰过的类不能被继承,如下的代码在ide中是会报错的. final class Father{ } //The type son cannot subclass the final class Fath…
package cn.temptation; public class Sample01 { public static void main(String[] args) { // 继承关系的子类可以重写父类给它的成员方法 // 有时,父类不希望它的成员方法被子类重写(覆盖),对于这种要求,如何处理? // 答:首先会想到把public 改为 private,但是这样会导致外部无法调用该方法.所以,Java提供了 final 关键字 // final 使用格式: // 修饰符 final 成员方…
