mapdemo.java

本java源程序包括了大量的学习程序（共27章）方便大家学习

package test;
import java.util.*;
public class MapDemo 
{
	public static void main(String argv[])
	{
		Map employers = new LinkedHashMap(10,0.75f,true);
		//定义Map对象employers，并设定其初始大小为10，容量超过75%自动增加，按顺序自动插入数据
		//以下将10个Employer对象加入到Map对象中
		employers.put("1111-01",new Employer("zhang",26,"male","manager",3000.0f));
		employers.put("1111-02",new Employer("li",25,"female","leader",2000.0f));
		employers.put("1111-03",new Employer("wang",24,"male","employer",1000.0f));
		employers.put("1111-04",new Employer("zhao",23,"female","employer",1000.0f));

		Set set = employers.entrySet();
		//将Map对象employers使用entrySet()方法转换成Set对象
		Iterator iterator = set.iterator();
        //将Set对象set使用iterator()方法转换成Iterator对象
		for(int i=0;i<employers.size();i++)
		{
			if(iterator.hasNext()) 
			{
				Map.Entry me= (Map.Entry)iterator.next();
				Employer employer = (Employer)me.getValue();
				//取出Map中对象，并转换为Employer对象
				System.out.println("The information of employer["+i+"]:");//输出该对象对应的key
				//以下输出取出的该对象的属性
				System.out.println("Key in map is:"+me.getKey());
				System.out.println("Name:"+employer.getName());
				System.out.println("Age:"+employer.getAge());
				System.out.println("Sex:"+employer.getSex());
				System.out.println("Post:"+employer.getPost());
				System.out.println("Salary:"+employer.getsalary());
				System.out.println();				
			}
		}
	    Employer a = (Employer)employers.get("1111-02");
	    //取出Map中键值key为"1111-02"所对应的对象，并转换为Employer的对象
	    System.out.print(a.getName());
		System.out.println("The information of employer key in map is \"1111-02\":");	
		System.out.println("Name:"+a.getName());
		System.out.println("Age:"+a.getAge());
		System.out.println("Sex:"+a.getSex());
		System.out.println("Post:"+a.getPost());
		System.out.println("Salary:"+a.getsalary());
		System.out.println();	
	}
}
class Employer  //雇员类，包含了雇员的部分属性和方法
{
	private String name;   //雇员的姓名
	private int age;       //雇员的年龄
	private String sex;    //雇员的性别
	private String post;   //雇员的职位
	private float salary;  //雇员的薪水
	public Employer(){}    //雇员类的默认构造方法
	public Employer(String name,int age,String sex,String post,float salary)
	{ //雇员类的构造方法，该构造方法可以初始化雇员类的对象
		this.name = name;
		this.age = age;
		this.sex = sex;
		this.post = post;
		this.salary = salary;
	}
	public String getName()  //得到雇员姓名的方法
	{
		return name;
	}
	public void setName(String str)  //设置雇员姓名的方法
	{
		this.name = str;
	}
	public int getAge()    //得到雇员年龄的方法
	{
		return age;
	}
	public void setAge(int age)  //设置雇员年龄的方法
	{
		this.age = age;
	}
	public String getSex()   //得到雇员性别的方法
	{
		return sex;
	}
	public void setSex(String sex)  //设置雇员性别的方法
	{
		this.sex = sex;
	}
	public String getPost()  //得到雇员职位的方法
	{
		return sex;
	}
	public void setPost(String post)  //设置雇员职位的方法
	{
		this.post = post;
	}
	public float getsalary()  //得到雇员薪水的方法
	{
		return salary;
	}
	public void setSalary(float salary)  //设置雇员薪水的方法
	{
		this.salary = salary;
	}		
}