1 /** 2 *homework0926 3 *@author:kai li 4 */ 5 package com.kai.li.homework0926; 6 import java.util.List; 7 import java.util.ArrayList; 8 import java.util.Arrays; 9 import java.util.Collections; 10 import java.util.Random; 11 import java.util.Map; 12 import java.util.HashMap; 13 import static java.util.stream.Collectors.toMap; 14 /** 15 *following class is client 16 */ 17 public class HomeWork0926{ 18 public static void main(String[] args)throws Exception{ 19 20 /** 21 *question four 22 */ 23 24 List<String> strList=new ArrayList<String>(); 25 strList.add("hello"); 26 strList.add("world"); 27 strList.add("learn"); 28 Collections.reverse(strList); 29 System.out.println(strList); 30 31 /** 32 *question five 33 */ 34 35 /*create data source*/ 36 List<Account> accounts=Arrays.asList(new Account(10.00,"1234"),new Account(15.00,"5678"),new Account(0.00,"1010")); 37 Map<Long,Account> accountMap=new HashMap<>(); 38 accountMap=accounts.stream().collect(toMap(i->i.getId(),i->i)); 39 System.out.println(accountMap); 40 41 /** 42 *question six 43 */ 44 45 /*creat data source*/ 46 47 List<Worker> workerList=new ArrayList<>(); 48 workerList.add(new Worker("zhang3",18,3000)); 49 workerList.add(new Worker("li4",25,3500)); 50 workerList.add(new Worker("wang5",22,3200)); 51 52 /*operate*/ 53 54 workerList.add(1,new Worker("zhao6",24,3300)); 55 workerList.remove(3); 56 57 //iterator 58 workerList.stream().forEach(System.out::println); 59 workerList.stream().forEach(Worker::work); 60 } 61 } 62 63 /** 64 *class for question five 65 */ 66 class Account{ 67 private long id; 68 private double balance; 69 private String password; 70 Account(double balance,String password){ 71 Random random=new Random(); 72 this.id=random.nextInt(100000)+100000; 73 this.balance=balance; 74 this.password=password; 75 } 76 public long getId(){ 77 return id; 78 } 79 public double getBalance(){ 80 return balance; 81 } 82 public String getPassword(){ 83 return password; 84 } 85 @Override 86 public String toString(){ 87 return "id:"+id+",balance:"+balance+" "; 88 } 89 } 90 91 /** 92 *class for question six 93 */ 94 class Worker{ 95 private int age; 96 private String name; 97 private double salary; 98 public Worker(){} 99 public Worker(String name,int age,double salary){ 100 this.name=name; 101 this.age=age; 102 this.salary=salary; 103 } 104 public int getAge(){ 105 return age; 106 } 107 public String getName(){ 108 return name; 109 } 110 public double getSalary(){ 111 return salary; 112 } 113 @Override 114 public String toString(){ 115 return "name:"+name+",age:"+age+",salary:"+salary; 116 } 117 public void work(){ 118 System.out.println(name+" work "); 119 } 120 }