这个版泵的银行管理系统，相对于以前的银行管理系统没有太大的变化，在原来版本的银行管理系统上加入了抽象类，同时加入了其他类型账户。
一.个人银行管理账户0.4
1.在使用体会this时，注意this所指向的对象或者指向的内容，
import static java.lang.Math.*;
public class Account{
private String id; //帐号
private double balance; //余额
private static double total; //所有账户的总金额
//供派生类调用的构造函数，id为账户
protected Account(final Date date, final String id) {
this.id=id;
this.balance=0;
date.show();
System.out.println("\t#"+id+ " created");
}
//记录一笔帐，date为日期，amount为金额，desc为说明
void record(final Date date, double amount, final String desc) {
amount = floor(amount * 100 + 0.5) / 100; //保留小数点后两位
balance += amount;
total += amount;
date.show();
System.out.println("\t#"+"\t"+amount+"\t"+balance+"\t"+desc);
}
//报告错误信息
void error(final String msg) {
System.out.println("Error(#"+id+"):"+msg);
}
public final String getId() { return id; }
public double getBalance() { return balance; }
public static double getTotal() { return total;}
//显示账户信息
void show() {
System.out.println(id+ "\tBalance: "+balance);
}
public static void main(String args[]) {
Date date=new Date(2008, 11, 1); //起始日期
//建立几个账户
SavingsAccount sa1=new SavingsAccount(date, "S3755217", 0.015);
SavingsAccount sa2=new SavingsAccount(date, "02342342", 0.015);
CreditAccount ca=new CreditAccount(date, "C5392394", 10000, 0.0005, 50);
//11月份的几笔账目
sa1.deposit(new Date(2008, 11, 5), 5000, "salary");
ca.withdraw(new Date(2008, 11, 15), 2000, "buy a cell");
sa2.deposit(new Date(2008, 11, 25), 10000, "sell stock 0323");
//结算信用卡
ca.settle(new Date(2008, 12, 1));
//12月份的几笔账目
ca.deposit(new Date(2008, 12, 1), 2016, "repay the credit");
sa1.deposit(new Date(2008, 12, 5), 5500, "salary");
//结算所有账户
sa1.settle(new Date(2009, 1, 1));
sa2.settle(new Date(2009, 1, 1));
ca.settle(new Date(2009, 1, 1));
//输出各个账户信息
System.out.println("\n");
sa1.show();System.out.println("\n");
sa2.show();System.out.println("\n");
ca.show(); System.out.println("\n");
System.out.println("Total:"+getTotal());
}
static class Date {
private int year; //年
private int month; //月
private int day; //日
private int totalDays;
final int DAYS_BEFORE_MONTH[] = { 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 365 };//该日期是从公元元年1月1日开始的第几天
public Date(int year, int month, int day) {
this.year=year;
this.month=month;
this.day=day;
if (day <= 0 || day > getMaxDay()) {
System.out.println("\"Invalid date: \"");
show();
System.out.println("\n");
System.exit(1);
}
int years = year - 1;
totalDays = years * 365 + years / 4 - years / 100 + years / 400
+ DAYS_BEFORE_MONTH[month - 1] + day;
if (isLeapYear() && month > 2) totalDays++;//用年、月、日构造日期{
}
int getYear() { return year; }
int getMonth() { return month; }
int getDay() { return day; }
int getMaxDay() {
if (isLeapYear() && month == 2)
return 29;
else
return DAYS_BEFORE_MONTH[month]- DAYS_BEFORE_MONTH[month - 1];//获得当月有多少天
}
boolean isLeapYear(){ //判断当年是否为闰年
return year % 4 == 0 && year % 100 != 0 || year % 400 == 0;
}
void show() {//输出当前日期
System.out.println(getYear()+"-"+getMonth()+"-"+getDay());
}
//计算两个日期之间差多少天
int distance(final Date date) {
return totalDays - date.totalDays;
}
}
static class SavingsAccount extends Account { //储蓄账户类
private Accumulator acc; //辅助计算利息的累加器
private double rate; //存款的年利率
//构造函数
public SavingsAccount(final Date date, final String id, double rate) {
super(date,id);
this.rate=rate;
this.acc=new Accumulator(date,0);
}
public double getRate() { return rate; }
//存入现金
public void deposit(final Date date, double amount, final String desc) {
record(date, amount, desc);
acc.change(date, getBalance());
}
//取出现金
void withdraw(final Date date, double amount, final String desc) {
record(date, amount, desc);
acc.change(date, getBalance());
}
//结算利息，每年1月1日调用一次该函数
void settle(final Date date) {
double interest = acc.getSum(date) * rate //计算年息
/ date.distance(new Date(date.getYear() - 1, 1, 1));
if (interest != 0)
record(date, interest, "interest");
acc.reset(date, getBalance());
}
}
static class CreditAccount extends Account { //信用账户类
private Accumulator acc; //辅助计算利息的累加器
private double credit; //信用额度
private double rate; //欠款的日利率
private double fee; //信用卡年费
private double getDebt() { //获得欠款额
double balance = getBalance();
return (balance < 0 ? balance : 0);
}
//构造函数
public CreditAccount(final Date date, final String id, double credit, double rate, double fee) {
super(date, id);
this.credit=credit;
this.rate=rate;
this.fee=fee;
this.acc=new Accumulator(date,0);
}
public double getCredit(){ return credit; }
public double getRate(){ return rate; }
public double getFee(){ return fee; }
public double getAvailableCredit(){ //获得可用信用
if (getBalance() < 0)
return credit + getBalance();
else
return credit;
}
//存入现金
public void deposit(final Date date, double amount, final String desc) {
record(date, amount, desc);
acc.change(date, getDebt());
}
//取出现金
public void withdraw(final Date date, double amount, final String desc) {
if (amount - getBalance() > credit) {
error("not enough credit");
} else {
record(date, -amount, desc);
acc.change(date, getDebt());
}
}
//结算利息和年费，每月1日调用一次该函数
void settle(final Date date) {
double interest = acc.getSum(date) * rate;
if (interest != 0)
record(date, interest, "interest");
if (date.getMonth() == 1)
record(date, -fee, "annual fee");
acc.reset(date, getDebt());
}
void show() {
super.show();
System.out.println("\tAvailable credit:" + getAvailableCredit());
}
}
class Accumulator { //将某个数值按日累加
private Date lastDate; //上次变更数值的时期
private double value; //数值的当前值
private double sum; //数值按日累加之和
//构造函数，date为开始累加的日期，value为初始值
public Accumulator(final Date date, double value) {
this.lastDate=date;
this.value=value;
this.sum=0;
}
//获得到日期date的累加结果
public double getSum(final Date date){
return sum + value * date.distance(lastDate);
}
//在date将数值变更为value
public void change(final Date date, double value) {
sum = getSum(date);
lastDate = date;
this.value = value;
}
//初始化，将日期变为date，数值变为value，累加器清零
public void reset(final Date date, double value) {
lastDate = date;
this.value = value;
sum = 0;
}
}
个人银行账户管理系统0.5
1.在对代码转换的时候对show（）函数有很大的困难，show函数定义为抽象类的产生了困惑，试过将show函数设置为抽象类，但是在通过子类调用这个抽象方法的时候就会产生错误，对于Java来说，抽象方法是只能声明函数和参数，具体的实现过程在子类中实现。
2.在实现从键盘读取输入可以用Scanner这个类，也可以用标准输入流。
import static java.lang.Math.*;
import java.util.Scanner;
abstract public class Account{
private String id; //帐号
private double balance; //余额
static double total; //所有账户的总金额
//供派生类调用的构造函数，id为账户
protected Account(final Date date, final String id) {
this.id=id;
this.balance=0;
date.show();
System.out.println("\t#"+id+"created");
}
//记录一笔帐，date为日期，amount为金额，desc为说明
protected void record(final Date date, double amount,final String desc) {
amount = floor(amount * 100 + 0.5) / 100; //保留小数点后两位
balance += amount;
total += amount;
date.show();
System.out.println("\t#"+id+"\t"+amount+"\t"+balance+"\t"+desc);
}
//报告错误信息
protected void error(final String msg) {
System.out.println("Error(#"+id+ "): " +msg);
}
public final String getId(){ return id; }
public double getBalance() { return balance; }
public static double getTotal() { return total; }
//存入现金，date为日期，amount为金额，desc为款项说明
abstract public void deposit(final Date date, double amount,final String desc);
//取出现金，date为日期，amount为金额，desc为款项说明
abstract public void withdraw(final Date date, double amount, final String desc);
//结算（计算利息、年费等），每月结算一次，date为结算日期
abstract public void settle(final Date date);
//显示账户信息
public void show() {
System.out.println(id+ "\tBalance: " +balance);
}
public static void main(String args[]){
Date date=new Date(2008, 11, 1); //起始日期
//建立几个账户
SavingsAccount sa1=new SavingsAccount(date, "S3755217", 0.015);
SavingsAccount sa2=new SavingsAccount(date, "02342342", 0.015);
CreditAccount ca=new CreditAccount(date, "C5392394", 10000, 0.0005, 50);
Account accounts[] = { sa1, sa2, ca };
final int n = 3; //账户总数
System.out.println("(d)deposit (w)withdraw (s)show (c)change day (n)next month (e)exit");
char cmd;
do {
//显示日期和总金额
date.show();
System.out.println("\tTotal: "+getTotal()+ "\tcommand> ");
int index, day;
double amount;
String desc;
cmd= new java.util.Scanner(System.in).next().charAt(0);
switch (cmd) {
case 'd': //存入现金
Scanner input1=new Scanner(System.in);
Scanner input2=new Scanner(System.in);
index=input1.nextInt();
amount=input2.nextDouble();
desc=new java.util.Scanner(System.in).next();
accounts[index].deposit(date, amount, desc);
break;
case 'w':
Scanner input3=new Scanner(System.in);
Scanner input4=new Scanner(System.in);//取出现金
index=input3.nextInt();
amount=input4.nextDouble();
desc=new java.util.Scanner(System.in).next();
accounts[index].withdraw(date, amount, desc);
break;
case 's': //查询各账户信息
for (int i = 0; i < n; i++) {
System.out.println("["+i+"] ");
accounts[i].show();
System.out.println('\n');
}
break;
case 'c'://改变日期
Scanner input5=new Scanner(System.in);
day=input5.nextInt();
if (day < date.getDay())
System.out.println( "You cannot specify a previous day");
else if (day > date.getMaxDay())
System.out.println("Invalid day");
else
date =new Date(date.getYear(), date.getMonth(), day);
break;
case 'n': //进入下个月
if (date.getMonth() == 12)
date = new Date(date.getYear() + 1, 1, 1);
else
date = new Date(date.getYear(), date.getMonth() + 1, 1);
for (int i = 0; i < n; i++)
accounts[i].settle(date);
break;
}
} while (cmd != 'e');
}
}
class SavingsAccount extends Account { //储蓄账户类
private Accumulator acc; //辅助计算利息的累加器
private double rate; //存款的年利率
//构造函数
public SavingsAccount(final Date date, final String id, double rate) {
super(date,id);
this.rate=rate;
this.acc=new Accumulator(date,0);
}
public double getRate(){ return rate; }
public void deposit(final Date date, double amount, final String desc) {
record(date, amount, desc);
acc.change(date, getBalance());
}
public void withdraw(final Date date, double amount,final String desc) {
if (amount > getBalance()) {
error("not enough money");
} else {
record(date, -amount, desc);
acc.change(date, getBalance());
}
}
public void settle(final Date date) {
if (date.getMonth() == 1) { //每年的一月计算一次利息
double interest = acc.getSum(date) * rate
/ date.distance(new Date(date.getYear() - 1, 1, 1));
if (interest != 0)
record(date, interest, "interest");
acc.reset(date, getBalance());
}
}
}
class CreditAccount extends Account { //信用账户类
private Accumulator acc; //辅助计算利息的累加器
private double credit; //信用额度
private double rate; //欠款的日利率
private double fee; //信用卡年费
private double getDebt(){ //获得欠款额
double balance = getBalance();
return (balance < 0 ? balance : 0);
}
//构造函数
public CreditAccount(final Date date, final String id, double credit, double rate, double fee) {
super(date,id);
this.credit=credit;
this.rate=rate;
this.fee=fee;
this.acc=new Accumulator(date,0);
}
public double getCredit(){ return credit; }
public double getRate() { return rate; }
public double getFee() { return fee; }
public double getAvailableCredit() { //获得可用信用
if (getBalance() < 0)
return credit + getBalance();
else
return credit;
}
public void deposit(final Date date, double amount, final String desc) {
record(date, amount, desc);
acc.change(date, getDebt());
}
public void withdraw(final Date date, double amount,final String desc) {
if (amount - getBalance() > credit) {
error("not enough credit");
} else {
record(date, -amount, desc);
acc.change(date, getDebt());
}
}
public void settle(final Date date) {
double interest = acc.getSum(date) * rate;
if (interest != 0)
record(date, interest, "interest");
if (date.getMonth() == 1)
record(date, -fee, "annual fee");
acc.reset(date, getDebt());
}
public void show() {
super.show();
System.out.println("\tAvailable credit:"+getAvailableCredit());
}
}
class Date {
int DAYS_BEFORE_MONTH[] = { 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 365 };//日期类
private int year; //年
private int month; //月
private int day; //日
private int totalDays; //该日期是从公元元年1月1日开始的第几天
public Date(int year, int month, int day) {
this.year=year;
this.month=month;
this.day=day;
if (day <= 0 || day > getMaxDay()) {
System.out.println( "Invalid date: ");
show();
System.out.println('\n');
System.exit(1);
}
int years = year - 1;
totalDays = years * 365 + years / 4 - years / 100 + years / 400
+ DAYS_BEFORE_MONTH[month - 1] + day;
if (isLeapYear() && month > 2) totalDays++;//用年、月、日构造日期
}
int getYear() { return year; }
int getMonth() { return month; }
int getDay() { return day; }
int getMaxDay() {
if (isLeapYear() && month == 2)
return 29;
else
return DAYS_BEFORE_MONTH[month]- DAYS_BEFORE_MONTH[month - 1];//获得当月有多少天
}
boolean isLeapYear() { //判断当年是否为闰年
return year % 4 == 0 && year % 100 != 0 || year % 400 == 0;
}
void show() {
System.out.println(getYear()+"-"+getMonth()+"-"+getDay());//输出当前日期
}
//计算两个日期之间差多少天
int distance(final Date date) {
return totalDays - date.totalDays;
}
}
class Accumulator { //将某个数值按日累加
private Date lastDate; //上次变更数值的时期
private double value; //数值的当前值
private double sum; //数值按日累加之和
//构造函数，date为开始累加的日期，value为初始值
public Accumulator(final Date date, double value) {
this.lastDate=date;
this.value=value;
this.sum=0;
}
//获得到日期date的累加结果
public double getSum(final Date date) {
return sum + value *date.distance(lastDate);
}
//在date将数值变更为value
void change( Date date, double value) {
sum = getSum(date);
lastDate = date;
this.value = value;
}
//初始化，将日期变为date，数值变为value，累加器清零
void reset(final Date date, double value) {
lastDate = date;
this.value = value;
sum = 0;
}
}
个人银行专户管理系统0.6
1.在修改代码的过程就卡在这里，在这个版本的银行账户管理系统中加入C++ 的模板，但是在Java中是没有C++中向template模板的，所以产生了困惑。最后决定用ArrayList这个类来解决这个问题。
import static java.lang.Math.*;
import java.util.ArrayList;
import java.util.Scanner;
abstract public class Account {
private String id; //帐号
private double balance; //余额
private static double total=0; //所有账户的总金额
//供派生类调用的构造函数，id为账户
protected Account(final Date date, final String id) {
this.id=id;
this.balance=0;
date.show();
System.out.println("\t#"+id+"created");
}
//记录一笔帐，date为日期，amount为金额，desc为说明
protected void record(final Date date, double amount, final String desc) {
amount = floor(amount * 100 + 0.5) / 100; //保留小数点后两位
balance += amount;
total += amount;
date.show();
System.out.println("\t#"+id+"\t"+amount+"\t"+balance+"\t"+desc);
}
//报告错误信息
protected void error(final String msg) {
System.out.println("Error(#"+id+"): "+msg);
}
public final String getId() { return id; }
public double getBalance() { return balance; }
public static double getTotal() { return total; }
//存入现金，date为日期，amount为金额，desc为款项说明
abstract void deposit(final Date date, double amount, final String desc);
//取出现金，date为日期，amount为金额，desc为款项说明
abstract void withdraw(final Date date, double amount,final String desc) ;
//结算（计算利息、年费等），每月结算一次，date为结算日期
abstract void settle(final Date date);
//显示账户信息
public void show() {
System.out.println(id+"\tBalance: "+balance);
}
public static void main(String args[]) {
Date date=new Date(2008, 11, 1);
ArrayList <Account> accounts=new ArrayList();//起始日期
System.out.println( "(a)add account (d)deposit (w)withdraw (s)show (c)change day (n)next month (e)exit" );
char cmd;
do {
//显示日期和总金额
date.show();
System.out.println("\tTotal: " +getTotal()+ "\tcommand> ");
char type;
int index, day;
double amount, credit, rate, fee;
String id, desc;
cmd=new java.util.Scanner(System.in).next().charAt(0);
switch (cmd) {
case 'a': //增加账户
type=new java.util.Scanner(System.in).next().charAt(0);
id=new java.util.Scanner(System.in).next();
if (type == 's') {
rate=new java.util.Scanner(System.in).nextDouble();
accounts.add(new SavingsAccount(date, id, rate));
} else {
credit=new java.util.Scanner(System.in).nextDouble();
rate=new java.util.Scanner(System.in).nextDouble();
fee=new java.util.Scanner(System.in).nextDouble();
accounts.add(new CreditAccount(date, id, credit,rate,fee));
}
break;
case 'd': //存入现金
index=new java.util.Scanner(System.in).nextInt();
amount=new java.util.Scanner(System.in).nextDouble();
desc=new java.util.Scanner(System.in).next();
accounts.get(index).deposit(date, amount, desc);
break;
case 'w': //取出现金
index=new java.util.Scanner(System.in).nextInt();
amount=new java.util.Scanner(System.in).nextDouble();
desc=new java.util.Scanner(System.in).next();
accounts.get(index).withdraw(date, amount, desc);
break;
case 's': //查询各账户信息
for (int i = 0; i < accounts.size(); i++) {
System.out.println("["+i+"] ");
accounts.get(i).show();
System.out.println('\n');
}
break;
case 'c': //改变日期
day=new java.util.Scanner(System.in).nextInt();
if (day < date.getDay())
System.out.println("You cannot specify a previous day");
else if (day > date.getMaxDay())
System.out.println("Invalid day");
else
date = new Date(date.getYear(), date.getMonth(), day);
break;
case 'n': //进入下个月
if (date.getMonth() == 12)
date = new Date(date.getYear() + 1, 1, 1);
else
date = new Date(date.getYear(), date.getMonth() + 1, 1);
for (int i = 0; i < accounts.size(); i++)
accounts.get(i).settle(date);
break;
}
} while (cmd != 'e');
}
}
class SavingsAccount extends Account { //储蓄账户类
private Accumulator acc; //辅助计算利息的累加器
private double rate; //存款的年利率
//构造函数
public SavingsAccount(final Date date, final String id, double rate) {
super(date,id);
this.rate=rate;
this.acc=new Accumulator(date,0);
}
public double getRate() { return rate; }
public void deposit(final Date date, double amount, final String desc) {
record(date, amount, desc);
acc.change(date, getBalance());
}
public void withdraw(final Date date, double amount, final String desc) {
if (amount > getBalance()) {
error("not enough money");
} else {
record(date, -amount, desc);
acc.change(date, getBalance());
}
}
public void settle(final Date date) {
if (date.getMonth() == 1) { //每年的一月计算一次利息
double interest = acc.getSum(date) * rate
/date.distance(new Date(date.getYear() - 1, 1, 1));
if (interest != 0)
record(date, interest, "interest");
acc.reset(date, getBalance());
}
}
}
class CreditAccount extends Account { //信用账户类
private Accumulator acc; //辅助计算利息的累加器
private double credit; //信用额度
private double rate; //欠款的日利率
private double fee; //信用卡年费
private double getDebt() { //获得欠款额
double balance = getBalance();
return (balance < 0 ? balance : 0);
}
//构造函数
public CreditAccount(final Date date, final String id, double credit, double rate, double fee) {
super(date,id);
this.credit=credit;
this.rate=rate;
this.fee=fee;
this.acc=new Accumulator(date,0);
}
public double getCredit() { return credit; }
public double getRate() { return rate; }
public double getFee() { return fee; }
public double getAvailableCredit() { //获得可用信用
if (getBalance() < 0)
return credit + getBalance();
else
return credit;
}
public void deposit(final Date date, double amount, final String desc) {
record(date, amount, desc);
acc.change(date, getDebt());
}
public void withdraw(final Date date, double amount, final String desc) {
if (amount - getBalance() > credit) {
error("not enough credit");
} else {
record(date, -amount, desc);
acc.change(date, getDebt());
}
}
public void settle(final Date date) {
double interest = acc.getSum(date) * rate;
if (interest != 0)
record(date, interest, "interest");
if (date.getMonth() == 1)
record(date, -fee, "annual fee");
acc.reset(date, getDebt());
}
public void show() {
super.show();
System.out.println("\tAvailable credit:"+getAvailableCredit());
}
}
class Date {
int DAYS_BEFORE_MONTH[] = { 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 365 };//日期类
private int year; //年
private int month; //月
private int day; //日
private int totalDays; //该日期是从公元元年1月1日开始的第几天
public Date(int year, int month, int day) {
this.year=year;
this.month=month;
this.day=day;//用年、月、日构造日期
if (day <= 0 || day > getMaxDay()) {
System.out.println("Invalid date: ");
show();
System.out.println('\n');
System.exit(1);
}
int years = year - 1;
totalDays = years * 365 + years / 4 - years / 100 + years / 400
+ DAYS_BEFORE_MONTH[month - 1] + day;
if (isLeapYear() && month > 2) totalDays++;
}
public int getYear() { return year; }
public int getMonth() { return month; }
public int getDay() { return day; }
public int getMaxDay() { //获得当月有多少天
if (isLeapYear() && month == 2)
return 29;
else
return DAYS_BEFORE_MONTH[month]- DAYS_BEFORE_MONTH[month - 1];
}
public boolean isLeapYear() { //判断当年是否为闰年
return year % 4 == 0 && year % 100 != 0 || year % 400 == 0;
}
public void show() {
System.out.println(getYear() +"-"+getMonth()+"-"+getDay());
}//输出当前日期
//计算两个日期之间差多少天
public int distance(final Date date) {
return totalDays - date.totalDays;
}
}
class Accumulator { //将某个数值按日累加
private Date lastDate; //上次变更数值的时期
private double value; //数值的当前值
private double sum; //数值按日累加之和
//构造函数，date为开始累加的日期，value为初始值
public Accumulator(final Date date, double value){
this.lastDate=date;
this.value=value;
this.sum=0;
}
//获得到日期date的累加结果
public double getSum(final Date date){
return sum + value *date.distance(lastDate);
}
//在date将数值变更为value
public void change(final Date date, double value) {
sum = getSum(date);
lastDate = date;
this.value = value;
}
//初始化，将日期变为date，数值变为value，累加器清零
public void reset(final Date date, double value) {
lastDate = date;
this.value = value;
sum = 0;
}
}
希望能过给有帮助的人，像我一样的。
