phonebook.java

java 教程相应的代码 全是自己写的内附注释 很容易看明白的

package demo.chapter09;

import java.util.HashMap;

public class PhoneBook {

	private static volatile PhoneBook me;

	private HashMap<String, Contect> map;
	private PhoneBook() {
		this.map = new HashMap<String, Contect>();
	}
	
	public static PhoneBook getInstance() {
		if (me == null)
			synchronized (PhoneBook.class) {
				if (me == null)
					me = new PhoneBook();
			}
		return me;
	}
	
	public Contect getContect(String name) {
		return map.get(name);
	}
	
	public void putContect(Contect t) {
		map.put(t.getName(), t);
	}
}