Pg168-1

1、Pg168-1

package org.hanqi.pn0120;

public class Computer {

    private double neicundx=10;

    public double getNeicundx()
    {
        return neicundx;
    }

    public void setNeicundx(double neicundx)
    {
        this.neicundx = neicundx;
    }

    public Computer()
    {

    }

    public static void main(String[] args)
    {
        Computer myComputer=new Computer();

         myComputer.setNeicundx(4);

        System.out.println("内存大小="  +myComputer.getNeicundx());
    }
}

课后练习

package org.hanqi.pn0120;

public class Text3 {

    public static void main(String[] args) {

        Computer myComputer1=new Computer();    

        System.out.println("myComputer1内存大小=" +myComputer1.getNeicundx());

    }
}

2、Pg167 单例模式的应用

package org.hanqi.pn0120;

public class Emperor {
    private static Emperor emperor=null;

    private Emperor()
    {    

    }
    public static Emperor getInstance()
    {
        if(emperor==null)
        {
            emperor=new Emperor();
        }
        return emperor;
    }
    public void getName()
    {
        System.out.println("我是皇帝：明日科技");
    }
}

单例模式的应用

package org.hanqi.pn0120;

public class Test {

    public static void main(String[] args) {

        System.out.println("创建皇帝1对象：");

        Emperor emperor1=Emperor.getInstance();

        emperor1.getName();

        System.out.println("创建皇帝2对象：");

        Emperor emperor2=Emperor.getInstance();

        emperor2.getName();

        System.out.println("创建皇帝3对象：");

        Emperor emperor3=Emperor.getInstance();

        emperor3.getName();

    }

}

单例模式的应用