keygenerator.java

来自「这是学习java与设计模式一书时所必备的源代码。只有这样才能更加深刻的理解编程的」· Java 代码 · 共 22 行

package com.javapatterns.keygen.ver1;

public class KeyGenerator
{
    private static KeyGenerator keygen =
        new KeyGenerator();

    private int key = 1000;

    private KeyGenerator() {}

    public static KeyGenerator getInstance()
    {
        return keygen;
    }

    public synchronized int getNextKey()
    {
        return key++;
    }
}