设计Account 对象如下: private long id; private double balance; private String password; 要求完善设计,使得该Account 对象能够自动分配id。 给定一个List 如下:
package homework005; public class Account { private long id; private double balance; private String password; public long getId() { return id; } public void setId(long id) { this.id = id; } public double getBalance() { return balance; } public void setBalance(double balance) { this.balance = balance; } public String getPassword() { return password; } public void setPassword(String password) { this.password = password; } public Account(long id, double balance, String password) { super(); this.id = id; this.balance = balance; this.password = password; } public Account() { super(); } @Override public String toString() { return "Account [id=" + id + ", balance=" + balance + ", password=" + password + "]"; } public Account(double balance, String password) { super(); this.balance = balance; this.password = password; } }
package homework005; import java.util.ArrayList; import java.util.HashMap; import java.util.List; import java.util.Map; public class Ls { public static void main(String[] args) { List<Account> list = new ArrayList<>(); list.add(new Account(10.00,"1234")); list.add(new Account(15.00,"5678")); list.add(new Account(0,"1010")); Map<Long, Account> map = new HashMap<>(); for(int i =0;i<=list.size()-1;i++) { map.put((long) i, list.get(i)); } for(long k:map.keySet()) { System.out.println("id="+k+" balance="+map.get(k).getBalance()); } } }