java-類的載入機制demo(一)
阿新 • • 發佈:2018-11-28
package com.test.testClass; public class Test { private static Test instance = new Test(); private static int x = 0; private static int y; private Test() { x++; y++; } private static Test getInstance() { return instance; } public static void main(String[] args) { Test test = Test.getInstance(); System.out.println(Test.x); System.out.println(Test.y); } }
package com.test.testClass; public class Test { private static int x = 0; private static int y; private static Test instance = new Test(); private Test() { x++; y++; } private static Test getInstance() { return instance; } public static void main(String[] args) { Test test = Test.getInstance(); System.out.println(Test.x); System.out.println(Test.y); } }
上下兩個程式輸出:
上:0 ,1
下:1, 1
原理是:類的載入機制(載入,連線(驗證,準備,解析),初始化)這個過程。