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  • Java中静态数据的初始化顺序

    Java的类中的数据成员中包含有静态成员(static)时,静态数据成员的初始化顺序是怎样的呢?

    【程序实例1】

    import java.util.*;
    import java.lang.*;
    import java.io.*;
    
    /* Name of the class has to be "Main" only if the class is public. */
    
    class Bowl {
        Bowl(int marker) {
            System.out.println("Bowl("+marker+")");
        }
        void f1(int marker) {
            System.out.println("f1("+marker+")");
        }
    }
    
    class Table {
        static Bowl bowl1=new Bowl(1);
        Table() {
            System.out.println("Table()");
            bowl2.f1(1);
        }
        void f2(int marker){
            System.out.println("f2("+marker+")");
        }
        static Bowl bowl2=new Bowl(2);
    }
    
    class Cupboard {
        Bowl bowl3=new Bowl(3);
        static Bowl bowl4=new Bowl(4);
        Cupboard() {
            System.out.println("Cupboard()");
            bowl4.f1(2);
        }
        void f3(int marker) {
            System.out.println("f3("+marker+")");
        }
        static Bowl bowl5=new Bowl(5);
    }
    
    class Ideone
    {
        public static void main (String[] args) //throws java.lang.Exception
        {
            System.out.println("Creating new Cupboard() in main");
            new Cupboard();
            System.out.println("Creating new Cupboard() in main");
            new Cupboard();
            table.f2(1);
            cupboard.f3(1);
        }
        
        static Table table=new Table();
        static Cupboard cupboard=new Cupboard();
    }

    【运行结果】

    Bowl(1)
    Bowl(2)
    Table()
    f1(1)
    Bowl(4)
    Bowl(5)
    Bowl(3)
    Cupboard()
    f1(2)
    Creating new Cupboard() in main
    Bowl(3)
    Cupboard()
    f1(2)
    Creating new Cupboard() in main
    Bowl(3)
    Cupboard()
    f1(2)
    f2(1)
    f3(1)
    

     从上面的执行结果可以看出:

      在初始化变量时,Java中static数据成员初始化优先于局部变量,先按定义的顺序初始化静态变量,然后是局部变量,最后执行类的构造函数。

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  • 原文地址:https://www.cnblogs.com/acode/p/5311240.html
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