package collections_example;
import java.util.*;
/**
*
* @author andy
*/
//定义Person类
class Person{
private String name;
private int age;
Person(String name, int age){
this.name=name;
this.age=age;
}
//重写Person类的toString()方法
@Override
public String toString(){
return “[name=”+this.name+”,age=”+this.age+”]”;
}
}
//定义一个HashMapSon类，它继承HashMap类
class HashMapSon<K,V> extends HashMap {
//重写HashMapSon类的toString()方法
@Override
public String toString(){
Set<Map.Entry<K,V>> keyset = this.entrySet();
Iterator<Map.Entry<K,V>> i = keyset.iterator();
if(!i.hasNext())
return “”;
StringBuffer buffer = new StringBuffer();
//buffer.append(“{“);