9.7（账户类Account）

package hello;

import java.util.Date;

public class Account {
public static void  main(String[] args) {
	//创建对象及初始数据
	Account account1 = new Account();
	account1.setId(1122);
	account1.setBalance(20000);
	account1.setAnnualInterestRate(4.5 / 100);
	
	account1.withDraw(2500);
	account1.deposite(3000);
	
	System.out.println(account1.balance);
	System.out.println(account1.balance * account1.annualInterestRate /12);
	System.out.println(account1.dateCreated);
}
private int id = 0;
private double balance = 0, annualInterestRate = 0;
private Date dateCreated = new Date();
public Account() {
	
}
public Account(int newId, double newBalance) {
	id = newId;
	balance = newBalance;
}

//ID的访问器和修改器
public int getId() {
	return id;
}
public void setId(int newId) {
	id = (newId >= 0) ? newId : 0;
}

public double getBalance() {
	return balance;
}
public void setBalance(double newBalance) {
	balance = (newBalance >= 0) ? newBalance : 0;
}

public double  getAnnualInterestRate() {
	return annualInterestRate;
}
public void setAnnualInterestRate(double newAnnualInterestRate) {
	annualInterestRate = (newAnnualInterestRate >= 0) ? newAnnualInterestRate : 0;
}
double getMonthlyIntererst(double annualInterestRate) {
    return annualInterestRate / 12;	
}
void withDraw(double withDraw) {
	balance -= withDraw;
}
void deposite(double deposite) {
	balance += deposite;
}
}