======第四周答题活动====== - 黑马程序员技术交流社区

package ts;
import java.io.BufferedReader;
import java.io.FileReader;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.Calendar;
import java.util.List;
import java.io.*;
public class Library {
public static ArrayList userList = new ArrayList();
public ArrayList getUserList()
{
return userList;
}
//将userList.txt中的信息保存至集合userList中
public static void loadUserList()
{
try
{
BufferedReader bufr = new BufferedReader(new FileReader("userList.txt"));
String line = null;
do
{
User user = new User();
for(int i = 0 ;i<3 ; i++)
{
if( i == 0)
{
line = bufr.readLine();
user.setUserName(line);
}
else if(i == 1)
{
line = bufr.readLine();
user.setTime(line);
}
else if(i == 2)
{
line = bufr.readLine();
//System.out.println(line);
if(line == null)
return;
Integer c = new Integer(line);
user.setCount(c);
}
}
userList.add(user);
}while(line != null);
}
catch (Exception e)
{
e.printStackTrace();
}
}
//将userList中的信息存入userList.txt中
public static void saveToTxt(ArrayList userList) throws Exception
{
FileWriter fw = new FileWriter("userList.txt",false);
fw.write("");
fw.flush();
System.out.println("文件已经清空！");
fw.close();
if(userList.size() == 0)
{
System.out.println("没有要保存的信息");
return;
}
BufferedWriter bufw = new BufferedWriter(new FileWriter("userList.txt",true));
for(int i = 0 ;i<userList.size(); i++)
{
User user = (User) userList.get(i);
String line1 = user.getUserName();
String line2 = user.getTime();
Integer line3 = user.getCount();
String l3 = line3.toString();
bufw.write(line1);
bufw.newLine();
bufw.write(line2);
bufw.newLine();
bufw.write(l3);
bufw.newLine();
bufw.flush();
}
System.out.println("信息保存完毕！！");
bufw.close();
}
//还书
public static void acceptReturn(String userName)
{
try
{
Calendar c = Calendar.getInstance();
int year = c.get(Calendar.YEAR);
int month = c.get(Calendar.MONTH);
int day = c.get(Calendar.DATE);
loadUserList();
for(int i = 0 ; i<userList.size(); i++)
{
User user = (User) userList.get(i);
//该用户借过书才能还书
if(user.getUserName().equals(userName))
{
System.out.println("借书时间："+user.getTime());
System.out.println("还书时间："+year+"/"+month+"/"+day);
//显示借书的借了多久，将年和月截取出来，只计算月数
String time = user.getTime();
String [] ymd = time.split("/");
//超过3个月罚款5元
if(year == new Integer(ymd[0]))
{
int borrMonth = new Integer(ymd[1]);
int overMonth = month - borrMonth;
System.out.println("已经借书"+overMonth+"月");
if(overMonth > 3)
{
int m = overMonth - 3;
System.out.println("超限"+m+"月"+",罚款"+m*1+"元");
userList.remove(i);
saveToTxt(userList);
System.out.println("还书完毕！！");
}
else
{
System.out.println("按时还书了！！！");
userList.remove(i);
saveToTxt(userList);
System.out.println("还书完毕！！");
}
}
else
{
System.out.println("超过一年，罚款10元");
userList.remove(i);
saveToTxt(userList);
System.out.println("还书完毕！！");
}
}
else
{
System.out.println("您没有借书！！");
}
}
}
catch (Exception e)
{
e.printStackTrace();
}
}
//登录后借书
public static void lend(String userName)
{
try
{
System.out.println("输入要借的书名：");
BufferedReader bufr =
new BufferedReader(new InputStreamReader(System.in));
String bookName = bufr.readLine();
boolean flag = searchBook(bookName);//看书是否存在
if(flag)
{
Library library = new Library();
library.yesOrNo(userName);//用户是否借书
}
else
System.out.println("该书不存在");
}
catch (Exception e)
{
e.printStackTrace();
}
}
//看该书是否存在
public static boolean searchBook(String bookName) throws Exception
{
BufferedReader br = new BufferedReader(new FileReader("book.txt"));
boolean flag = false;
String line = null;
//从文件中读取并
while((line = br.readLine())!=null)
{
if(line.equals(bookName))
{
flag = true;
break;
}
}
br.close();
return flag;
}
//借书
public static void yesOrNo(String userName)throws Exception
{
System.out.println("该书存在,是否要借？（是Y，不是N）");
BufferedReader bufr =
new BufferedReader(new InputStreamReader(System.in));
String yesOrNo = bufr.readLine();
if(yesOrNo.equals("Y"))
{
System.out.println(userName);
userBorrow(userName);
}
else if(yesOrNo.equals("N"))
{
System.out.println("没有借该书");
}
else
System.out.println("输入有误，请按照提示输入");
}
public static void userBorrow(String userName) throws Exception
{
//将用户信息添加进去
Calendar c = Calendar.getInstance();
String time = c.get(Calendar.YEAR)+"/"+c.get(Calendar.MONTH)+"/"+c.get(Calendar.DATE);
System.out.println(time);
//遍历集合，看该用户是否借书了
boolean flag = false;
User userFlag = null;
loadUserList();
for(int i = 0 ; i<userList.size(); i++)
{
User user = (User) userList.get(i);
//该用户曾经借过书
if(user.getUserName().equals(userName))
{
flag = true;
userFlag = user;
}
}
if(flag)
{
if(userFlag.getCount()<3)
{
int count = userFlag.getCount()+1;
userFlag.setCount(count);
userFlag.setTime(time);
saveToTxt(userList);
userList.clear();
System.out.println("借书成功");
}
else
{
System.out.println("已经借3次，不能再借！！！");
}
}
//该用户没有借过书
else
{
System.out.println("没有借书，或者借书都已经归还");
User userNew = new User();
userNew.setTime(time);
userNew.setUserName(userName);
userNew.setCount(1);
userList.add(userNew);
saveToTxt(userList);
userList.clear();
System.out.println("借书成功！！！");
}
}
}

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package ts;
public class User {
private String userName;
private String time;
private int count;
User()
{
}
User(String userName, String time, int count)
{
this.userName = userName;
this.time = time;
this.count = count;
}
public String getUserName()
{
return userName;
}
public void setUserName(String userName)
{
this.userName = userName;
}
public String getTime()
{
return time;
}
public void setTime(String time )
{
this.time = time;
}
public int getCount()
{
return count;
}
public void setCount(int count)
{
this.count = count;
}
}

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/**
*当前为了测试方便，将超期时间设计为20秒；
* 2013年7月14日下午6:26:50
* BookManager.java
* Administrator
* 1、假设书库只有一本书，书名Java，其他信息自设
2、这个系统具有借书和还书的功能
3、当借书时，要记录住借书人的姓名，借书时间，借书次数（每人只能借3次，且有书没还之前不能借书）
4、设定一个还书期限，当还书时，显示借了多久，如果超过期限，提示要借书人交一定的超限金额。
5、借书人先输入自己的名字，如果不存在，提示他是否需要注册，如果不注册就不能借书。
注册时，删除输入的用户名中的空格，并存储相关信息（如有没有借书，借书时间，借书次数）。
6、根据用户从键盘输入的进行相应操作
（可能用到知识点：面向对象，IO流操作，集合、配置文件，时间类，接口等）
*/
package com.itheima.test;
import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.OutputStream;
import java.io.RandomAccessFile;
import java.io.Serializable;
import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;
/**
* @author Administrator
* @time 2013年7月14日下午6:26:50
*/
public class BookManager {
//定义存储读者信息和书籍信息的位置
private File readersDir=new File("D:/temp/BookManager/Readers");
private File booksDir=new File("D:/temp/BookManager/Books");
private void init() throws Exception{
//初始化，若没有文件夹，就创建，若得不到Java的书籍信息，就创建一个份java的书籍信息
if(!readersDir.exists())
readersDir.mkdirs();
if(!booksDir.exists())
booksDir.mkdirs();
Book book=(Book)getResource("Java", booksDir);
if(book==null){
book=new Book("Java", "JavaWriter");
writeResource("Java",booksDir,book);
}
}
public BookManager()throws Exception{
//初始化
init();
//程序开始了
begin();
}
public void begin()throws Exception{
System.out.println("用户名中的空格将会自动清除！");
System.out.println("请出入用户名： ");
String name=ask();
String order="";
//读取用户信息，若用户为空，就提示注册用户
Reader reader=(Reader) getResource(name, readersDir);
if(reader==null)
{
System.out.println("该用户名不存在，是否注册？不注册将无法使用本系统功能，输入1注册，输入其他退出系统");
order=ask();
if(order.equals("1"))
{
reader=new Reader(name);
writeResource(name, readersDir, reader);
}
else{
System.exit(0);
}
}
while(true){
System.out.println("您好，"+reader.getName());
Book book=reader.getBook();
//先判断是否有未还的书籍，若有，则提示要还书
if(book!=null){
System.out.println("当前已经借一本书，书名为"+book.getName()+",输入1还书，输入over退出，不还书将无法借书，输入其他无效");
order=ask();
if(order.equals("1"))
{
//还书完成后，存储信息
reader.returnbook(book);
writeResource(name, readersDir, reader);
writeResource(book.getName(), booksDir, book);
}
}//如果读者已经接了三本书了，就不让他使用系统了
else if(reader.getTimes()>2)
{
System.out.println("你已经借过三次书了，且没有书未还，业务功能已经全部完成，系统退出");
System.exit(0);
}
else{
System.out.println("当前未借书，已经借书"+reader.getTimes()+"次,还可以借书"+(3-reader.getTimes())+"次,输入1借书，输入over退出，输入其他无效");
order=ask();
if(order.equals("1"))
{
System.out.println("请输入书名，书名中空格将被清除");
order=ask();
book=(Book) getResource(order, booksDir);
//判断是存在书籍
if(book==null)
{
System.out.println("书库中没有名为"+order+"的书");
}else{
//书籍已经被借走了
if(book.getReader()!=null)
{
System.out.println("该书已经被借走，您可以选择其他书籍借阅");
}
else{
//书籍未被借走
System.out.println(book.toString());
System.out.println("是否借书？输入1确认，输入over退出，输入其他无效");
order=ask();
if(order.equals("1")){
//存储信息
reader.borrow(book);
writeResource(name, readersDir, reader);
writeResource(book.getName(), booksDir, book);
SimpleDateFormat sdf = new SimpleDateFormat("yyyy年MM月dd日 HH点mm分ss秒");
System.out.println("借书成功，借书时间为"+sdf.format(new Date(reader.getBorrowTime())));
}
}
}
}
}
}
}
public Object getResource(String name ,File file) throws Exception{
//读取一个资源的信息，比如读者的信息，比如书籍的信息
File objectFile=new File(file, name+".dat");
if(objectFile.exists())
{
InputStream is=new FileInputStream(objectFile);
ObjectInputStream ois=new ObjectInputStream(is);
Object object =(Object)ois.readObject();
ois.close();
is.close();
return object;
}
return null;
}
public void writeResource(String name,File file,Object obj) throws Exception{
//存储读者书籍信息
File objectFile=new File(file, name+".dat");
OutputStream ops=new FileOutputStream(objectFile);
ObjectOutputStream oos=new ObjectOutputStream(ops);
oos.writeObject(obj);
oos.close();
ops.close();
}
BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
public String ask() throws Exception{
//从键盘获取用户输入，并且去除空格，判断是否为over
String message=br.readLine();
message=message.replaceAll(" ", "");
if(message.equals("over"))
{
System.out.println("退出系统，再见");
System.exit(0);
}
return message;
}
public static void main(String[] args) throws Exception {
new BookManager();
}
}
class Book implements Serializable{
private String name;
private String writer;
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getWriter() {
return writer;
}
public void setWriter(String writer) {
this.writer = writer;
}
public Reader getReader() {
return reader;
}
public void setReader(Reader reader) {
this.reader = reader;
}
public Book(String name,String writer){
this.name=name;
this.writer=writer;
}
private Reader reader;
/* (non-Javadoc)
* @see java.lang.Object#toString()
*/
@Override
public String toString() {
//输出书籍信息
return "书名 :"+name+" 作者："+writer;
}
}
class Reader implements Serializable{
private String name;
private long borrowTime;
private int times=0;
private Book book;
public String getName() {
return name;
}
/**
@function:
* @data:2013-7-16下午2:57:06
* @author Administrator
* @param book
*/
public void returnbook(Book book) {
//还书操作，并且计算是否超期，这里为了便于演示，超期时间设置为20秒；
this.book=null;
book.setReader(null);
long time=(System.currentTimeMillis()-this.borrowTime)/1000;
long extendstime=(time-20)>0?time-20:0;
Date date=new Date(borrowTime);
SimpleDateFormat sdf = new SimpleDateFormat("yyyy年MM月dd日 HH点mm分ss秒");
System.out.println("借书时间"+sdf.format(date)+",本次借书"+time+"秒，超期"+extendstime+"秒,应付"+extendstime*0.01+"元");
}
public void setName(String name) {
this.name = name;
}
public long getBorrowTime() {
return borrowTime;
}
public void setBorrowTime(long borrowTime) {
this.borrowTime = borrowTime;
}
public int getTimes() {
return times;
}
public void setTimes(int times) {
this.times = times;
}
public Book getBook() {
return book;
}
public void setBook(Book book) {
this.book = book;
}
public Reader(String name){
this.name=name;
}
public void borrow(Book book){
//借书操作
this.book=book;
book.setReader(this);
times++;
this.borrowTime=System.currentTimeMillis();
}
}

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package ts;
import java.io.BufferedReader;
import java.io.InputStreamReader;
//系统入口
public class BookManagementSystem
{
public static void main(String[] args)
{
while(true)
{
System.out.println("1.登录 2.注册 3.退出");
BufferedReader bufr =
new BufferedReader(new InputStreamReader(System.in));
try
{
String num = bufr.readLine();
if( num.equals("1"))
{
System.out.println("输入用户名：");
String userName = bufr.readLine();
Login login = new Login();//定义一个登录类，管理用户登录后的操作
login.receive(userName);//该操作接收到输入的用户名后对其判断
}
else if(num.equals("2"))
{
System.out.println("输入要注册的用户名：");
String registerName = bufr.readLine();
Register register = new Register();//获取用户名并将其写入到user.txt中
register.receive(registerName);//获取用户名并将其写入到user.txt中
}
else if(num.equals("3"))
{
System.out.println("退出成功");
break;
}
else
System.out.println("输入有误，请按需求输入 1 2 3");
}
catch (Exception e)
{
e.printStackTrace();
}
}
}
}

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package ts;
import java.io.BufferedReader;
import java.io.FileReader;
import java.io.InputStreamReader;
//登录
public class Login {
public static void receive(String userName)
{
try
{
BufferedReader bufr = new BufferedReader(new FileReader("user.txt"));
boolean flag = false;
String line = null;
//遍历user.txt,看用户是否存在
while((line = bufr.readLine())!=null)
{
if(line.equals(userName))
{
flag = true;
break;
}
}
bufr.close();
if(flag)
{
while(true)
{
BufferedReader br =
new BufferedReader(new InputStreamReader(System.in));
System.out.println(userName+",已登录");
System.out.println("请选择：1.借书 2.还书 3.退出");
String num = br.readLine();
if(num.equals("1"))
{
System.out.println("开始借书");
Library library = new Library();
library.lend(userName);//开始在图书馆借书
continue;
}
else if(num.equals("2"))
{
System.out.println(userName+"开始还书");
Library library = new Library();
library.acceptReturn(userName);//开始在图书馆借书
continue;
}
else if(num.equals("3"))
{
System.out.println("退出成功");
break;
}
else
{
System.out.println("输入有误，请输入1 或者2 或者3");
break;
}
}
}
else
{
System.out.println(userName+",用户名不存在，请注册");
return;
}
}
catch (Exception e)
{
e.printStackTrace();
}
}
}

复制代码

package ts;
import java.io.BufferedReader;
import java.io.FileReader;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.Calendar;
import java.util.List;
import java.io.*;
public class Library {
public static ArrayList userList = new ArrayList();
public ArrayList getUserList()
{
return userList;
}
public static void loadUserList()
{
try
{
BufferedReader bufr = new BufferedReader(new FileReader("userList.txt"));
String line = null;
do
{
User user = new User();
for(int i = 0 ;i<4 ; i++)
{
if( i == 0)
{
line = bufr.readLine();
user.setUserName(line);
}
else if(i == 1)
{
line = bufr.readLine();
user.setTime(line);
}
else if(i == 2)
{
line = bufr.readLine();
if(line == null)
return;
Integer c = new Integer(line);
user.setCount(c);
}
else if(i == 3)
{
line = bufr.readLine();
if(line.equals("0"))
{
user.setBorrowOrNot(0);
}
else if(line.equals("1"))
{
user.setBorrowOrNot(1);
}
}
}
userList.add(user);
}while(line != null);
}
catch (Exception e)
{
e.printStackTrace();
}
}
public static void saveToTxt(ArrayList userList) throws Exception
{
FileWriter fw = new FileWriter("userList.txt",false);
fw.write("");
fw.flush();
System.out.println("文件已经清空！");
fw.close();
if(userList.size() == 0)
{
System.out.println("没有要保存的信息");
return;
}
BufferedWriter bufw = new BufferedWriter(new FileWriter("userList.txt",true));
for(int i = 0 ;i<userList.size(); i++)
{
User user = (User) userList.get(i);
String line1 = user.getUserName();
String line2 = user.getTime();
Integer line3 = user.getCount();
String l3 = line3.toString();
Integer line4 = user.getBorrowOrNot();
String l4 = line4.toString();
bufw.write(line1);
bufw.newLine();
bufw.write(line2);
bufw.newLine();
bufw.write(l3);
bufw.newLine();
bufw.write(l4);
bufw.newLine();
bufw.flush();
}
System.out.println("信息保存完毕！！");
bufw.close();
}
public static void acceptReturn(String userName)
{
try
{
Calendar c = Calendar.getInstance();
int year = c.get(Calendar.YEAR);
int month = c.get(Calendar.MONTH);
int day = c.get(Calendar.DATE);
userList.clear();
loadUserList();
boolean flag = false;
for(int i = 0 ; i<userList.size(); i++)
{
User user = (User) userList.get(i);
System.out.println(user.getUserName());
if(user.getUserName().equals(userName))
{
flag = true;
if( user.getBorrowOrNot() == 1)//有书未还
{
System.out.println("借书时间："+user.getTime());
System.out.println("还书时间："+year+"/"+month+"/"+day);
String time = user.getTime();
String [] ymd = time.split("/");
if(year == new Integer(ymd[0]))
{
int borrMonth = new Integer(ymd[1]);
int overMonth = month - borrMonth;
System.out.println("已经借书"+overMonth+"月");
if(overMonth > 3)
{
int m = overMonth - 3;
System.out.println("超限"+m+"月"+",罚款"+m*1+"元");
User currUser = (User) userList.get(i);
currUser.setBorrowOrNot(0);
saveToTxt(userList);
userList.clear();
System.out.println("还书完毕！！");
break;
}
else
{
System.out.println("按时还书了！！！");
User currUser = (User) userList.get(i);
currUser.setBorrowOrNot(0);
saveToTxt(userList);
userList.clear();
System.out.println("还书完毕！！");
break;
}
}
else
{
System.out.println("超过一年，罚款10元");
User currUser = (User) userList.get(i);
currUser.setBorrowOrNot(0);//将是否借书标记为否
saveToTxt(userList);
userList.clear();
System.out.println("还书完毕！！");
break;
}
}
else if(user.getBorrowOrNot() == 0)
{
System.out.println("借书已还，无需再还！！！");
break;
}
}
}
if(!flag)
{
System.out.println("您从没有借过书！！！");
return;
}
}
catch (Exception e)
{
e.printStackTrace();
}
}
//登录后借书
public static void lend(String userName)
{
try
{
if(judgeUserName(userName) == null)
{
System.out.println("输入要借的书名：");
BufferedReader bufr =
new BufferedReader(new InputStreamReader(System.in));
String bookName = bufr.readLine();
boolean flag = searchBook(bookName);
if(flag)
{
newUseryesOrNo(userName);
}
else
System.out.println("该书不存在");
}
else if(judgeUserName(userName) != null)
{
User user = judgeUserName(userName);
if(user.getBorrowOrNot() == 1)
{
System.out.println("有书未还，不能借书");
return;
}
else if(user.getBorrowOrNot() == 0)
{
if(user.getCount() >= 3)
{
System.out.println("借书次数超过3次，不能再借");
}
else //可以借书了
{
System.out.println("输入要借的书名：");
BufferedReader bufr =
new BufferedReader(new InputStreamReader(System.in));
String bookName = bufr.readLine();
boolean flag = searchBook(bookName);//看书是否存在
if(flag)
{
oldUseryesOrNo(userName);//用户是否借书
}
else
System.out.println("该书不存在");
}
}
}
}
catch (Exception e)
{
e.printStackTrace();
}
}
public static void oldUserBorrow(String userName)
{
userList.clear();
loadUserList();
User user = null;
Calendar c = Calendar.getInstance();
String time = c.get(Calendar.YEAR)+"/"+c.get(Calendar.MONTH)+"/"+c.get(Calendar.DATE);
for(int i = 0; i<userList.size(); i++)
{
user = (User) userList.get(i);
if(user.getUserName().equals(userName))
{
user.setTime(time);
user.setBorrowOrNot(1);//改为1表示借书未还
user.setCount(user.getCount()+1);
try
{
saveToTxt(userList);
userList.clear();
System.out.println("借书成功");
}
catch (Exception e)
{
e.printStackTrace();
}
}
}
}
//用户是否曾经借过书
public static User judgeUserName(String userName)
{
User user = null;
userList.clear();
loadUserList();
for(int i = 0; i<userList.size(); i++)
{
user = (User) userList.get(i);
if(user.getUserName().equals(userName))
{
return user;
}
}
return null;
}
//看该书是否存在
public static boolean searchBook(String bookName) throws Exception
{
BufferedReader br = new BufferedReader(new FileReader("book.txt"));
boolean flag = false;
String line = null;
//从文件中读取并
while((line = br.readLine())!=null)
{
if(line.equals(bookName))
{
flag = true;
break;
}
}
br.close();
return flag;
}
//借书
public static void newUseryesOrNo(String userName)throws Exception
{
System.out.println("该书存在,是否要借？（是Y，不是N）");
BufferedReader bufr =
new BufferedReader(new InputStreamReader(System.in));
String yesOrNo = bufr.readLine();
if(yesOrNo.equals("Y"))
{
System.out.println(userName);
newUserBorrow(userName);
}
else if(yesOrNo.equals("N"))
{
System.out.println("没有借该书");
}
else
System.out.println("输入有误，请按照提示输入");
}
public static void oldUseryesOrNo(String userName)throws Exception
{
System.out.println("该书存在,是否要借？（是Y，不是N）");
BufferedReader bufr =
new BufferedReader(new InputStreamReader(System.in));
String yesOrNo = bufr.readLine();
if(yesOrNo.equals("Y"))
{
System.out.println(userName);
oldUserBorrow(userName);
}
else if(yesOrNo.equals("N"))
{
System.out.println("没有借该书");
}
else
System.out.println("输入有误，请按照提示输入");
}
public static void newUserBorrow(String userName) throws Exception
{
//将用户信息添加进去
Calendar c = Calendar.getInstance();
String time = c.get(Calendar.YEAR)+"/"+c.get(Calendar.MONTH)+"/"+c.get(Calendar.DATE);
System.out.println(time);
System.out.println("第一次借书");
User userNew = new User();
userNew.setTime(time);
userNew.setUserName(userName);
userNew.setCount(1);
userNew.setBorrowOrNot(1);
userList.add(userNew);
saveToTxt(userList);
userList.clear();
System.out.println("借书成功！！！");
}
}

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