泛型与集合实验

泛型与集合实验

有10名员工，其属性有工号和工资。编写一个程序，使用TreeMap<K,V>，分别按照工号和工资排序输出所有员工的信息。

提示：TreeMap<K,V>以下两个成员方法可供使用：

public Set keySet()

Returns a Set view of the keys contained in this map. The set's iterator returns the keys in ascending order.

public Collection values()

Returns a Collection view of the values contained in this map. The collection's iterator returns the values in ascending order of the corresponding keys.

import java.util.*;
class salary implements Comparable {
    double key=0;
    salary(double d) {
        key=d;
    }
    public int compareTo(Object b) {
        salary disc=(salary)b;
        if((this.key-disc.key)==0)
            return -1;
        else
            return (int)((this.key-disc.key)*1000);
    }
}
class Number{
    int number;
    double price;
    Number(int m,double e) {
        number=m;
        price=e;
    }
}
public class t5 {
    public static void main(String args[ ]) {
        TreeMap<salary,Number>  treemap= new TreeMap<salary,Number>();
        int amount[]={12,23,15,17,24,19,22,18,20,25,10};
        double price[]={40,20,10,80,30,22,38,32,25,16};
        Number UDisc[]=new Number[10];
        for(int k=0;k<UDisc.length;k++) {
            UDisc[k]=new Number(amount[k],price[k]);
        }
        salary key[]=new salary[10];
        for(int k=0;k<key.length;k++) {
            key[k]=new salary(UDisc[k].number);        }
        for(int k=0;k<UDisc.length;k++) {
            treemap.put(key[k],UDisc[k]);                 }
        int number=treemap.size();
        Collection<Number> collection=treemap.values();
        Iterator<Number> iter=collection.iterator();
        System.out.println("按照工号排列：");
        System.out.println("工号"+"   "+"工资");
        while(iter.hasNext()) {
            Number disc=iter.next();
            System.out.println(+disc.number+"     "+disc.price+"千元");       }
        treemap.clear();
        for(int k=0;k<key.length;k++) {
            key[k]=new salary(UDisc[k].price);       }
        for(int k=0;k<UDisc.length;k++) {
            treemap.put(key[k],UDisc[k]);       }
        number=treemap.size();
        collection=treemap.values();
        iter=collection.iterator();
        System.out.println("按照工资排列：");
        System.out.println("工资"+"        "+"工号");
        while(iter.hasNext()) {
            Number disc=iter.next();
            System.out.println(disc.price+"千元"+"     "+disc.number);
        }
    }
}