public class Operate implements Serializable {
    public Operate(){
        this.list = new ArrayList<>();
    }
    private List<Person> list ;
    /**-
     * 用户添加记录业务逻辑控制
     */
    public void addLogic(){
        Menu menu =new Menu();
        TelNoteRegex telNoteRegex =new TelNoteRegex();
        while (true){
            menu.addMenu();
            int item = telNoteRegex.menuItemValidate(1,3);
            switch (item){
                case 1:
                    this.addOperation();
                    break;
                case 2:
                    this.showAll();
                    break;
                case 3:
                    return;//主菜单未关闭，return可以关闭当前菜单
            }
        }
    }

    /**
     * 用户查询记录业务逻辑控制
     */
    public void searchLogic() {
        Menu menu = new Menu();
        TelNoteRegex telNoteRegexk = new TelNoteRegex();

        while (true){
            menu.searchMenu();
            int item = telNoteRegexk.menuItemValidate(1,7);
            switch (item){
                case 1: this.searchByName();break;
                case 2:this.searchByAge();break;
                case 3:this.searchBySex();break;
                case 4:this.searchByTelNum();break;
                case 5:this.searchByAdd();break;
                case 6:this.showAll();break;
                case 7:return;
            }
        }
    }
    /**
     * 修改记录业务逻辑控制
     */
    public void modifyLogic(){
        Menu menu =new Menu();
        TelNoteRegex telNoteRegex = new TelNoteRegex();
        while (true){
            menu.modifyMenu();
            int item = telNoteRegex.menuItemValidate(1,3);
            switch (item){
                case 1: this.showAll();break;
                case 2: this.modifyOperation();break;
                case 3: return;
            }
        }
    }
    /**
     * 删除记录业务逻辑控制
     */
    public void deleteLogic(){
        Menu menu =new Menu();
        TelNoteRegex telNoteRegex = new TelNoteRegex();
        while (true) {
            menu.deleteMenu();
            int item = telNoteRegex.menuItemValidate(1,4);
            switch (item){
                case 1:this.showAll();break;
                case 2:this.deleteOperation();break;
                case 3:this.deleteAllOperation();break;
                case 4:return;
            }
        }


    }
    /**
     * 排序记录业务逻辑控制
     */
    public void  orderLogic(){
        Menu menu =new Menu();
        TelNoteRegex telNoteRegex = new TelNoteRegex();
        menu.deleteMenu();
        int item = telNoteRegex.menuItemValidate(1,4);
        switch (item){
            case 1:this.orderName();break;
            case 2:this.orderAge();break;
            case 3:this.orderSex();break;
            case 4:this.showAll();break;
            case 5:return;
        }
    }



    /**
     *  添加新记录信息
     */
    public void addOperation () {
        TelNoteRegex telNoteRegex =new TelNoteRegex();
        String name = telNoteRegex.nameValidate();
        String age = telNoteRegex.ageValidate();
        String address = telNoteRegex.addressValidate();
        String sex = telNoteRegex.sexValidate();
        String telnum = telNoteRegex.telNumValidate();
        Person person =new Person(name,age,sex,telnum,address);
        this.list.add(person);
        person.setId(this.list.size());
        this.OutStream();





    }

    /**
     * 查询全部记录
     */
    public void showAll() {
        this.InStream();
        if (this.list.size()==0){
            System.out.println("没有任何记录");
        }
        for (int i =0;i<this.list.size();i++){
            System.out.println(this.list.get(i));
        }



    }

    /**
     * 按姓名查询记录
     * 姓名必须完全匹配
     */
    public void searchByName() {
        TelNoteRegex telNoteRegex =new TelNoteRegex();
        System.out.println("请输入姓名");
        String searchingName = telNoteRegex.nameValidate();
        for (int i = 0;i<this.list.size();i++){
            if (searchingName.equals(list.get(i).getName())){
                System.out.println(this.list.get(i));
            }else {
                System.out.println("没有此人");
            }
        }




    }

    /**
     * 按年龄查询记录
     */
    public void searchByAge() {
        TelNoteRegex telNoteRegex =new TelNoteRegex();
        System.out.println("请输入年龄");
        String age = telNoteRegex.ageValidate();
        for (int i =0;i<this.list.size();i++){
            if (age.equals(list.get(i).getAge())){
                System.out.println(this.list.get(i));
            }else{
                System.out.println("没有此年龄记录");
            }

        }

    }

    /**
     * 按性别查询记录
     */
    public void searchBySex() {
        TelNoteRegex telNoteRegex =new TelNoteRegex();
        System.out.println("请输入性别");
        String sex = telNoteRegex.sexValidate();
        boolean flag = true;
        for (int i = 0; i<this.list.size();i++){
            if (sex.equals(list.get(i).getSex())){
                System.out.println(this.list.get(i));
                flag  = false;
            }
            if (flag){
                System.out.println("没有此性别记录");
            }

        }

    }

    /**
     * 按电话号码查询记录
     */
    public void searchByTelNum() {
        TelNoteRegex telNoteRegex =new TelNoteRegex();
        System.out.println("请输入电话号码");
        String telnum = telNoteRegex.telNumValidate();
        boolean flag = true;
        for (int i = 0; i<this.list.size();i++){
            if (telnum.equals(list.get(i).getTelNum())){
                System.out.println(this.list.get(i));
                flag  = false;
            }
            if (flag){
                System.out.println("没有此电话记录");
            }

        }

    }

    /**
     * 按地址查询记录
     */
    public void searchByAdd() {
        TelNoteRegex telNoteRegex =new TelNoteRegex();
        System.out.println("请输入地址");
        String add = telNoteRegex.addressValidate();
        boolean flag = true;
        for (int i = 0; i<this.list.size();i++){
            if (add.equals(list.get(i).getAddress())){
                System.out.println(this.list.get(i));
                flag  = false;
            }
            if (flag){
                System.out.println("没有此地址记录");
            }

        }

    }

    /**
     * 修改指定记录
     */
    public void modifyOperation() {
        TelNoteRegex telNoteRegex =new TelNoteRegex();
        Menu menu = new Menu();
        //对序号验证，在有效范围内
        System.out.println("请输入记录的序号");
        int itemNum = telNoteRegex.menuItemValidate(1,this.list.size());
        switch (itemNum){
            case 1:
                String name = telNoteRegex.nameValidate();
                this.list.get(itemNum-1).setName(name);
                this.OutStream();
                break;
            case 2:
                String age = telNoteRegex.ageValidate();
                this.list.get(itemNum-1).setAge(age);
                this.OutStream();
                break;
            case 3:
                String sex = telNoteRegex.sexValidate();
                this.list.get(itemNum-1).setSex(sex);
                this.OutStream();
                break;
            case 4:
                String telnum = telNoteRegex.telNumValidate();
                this.list.get(itemNum-1).setTelNum(telnum);
                this.OutStream();
                break;
            case 5:
                String address = telNoteRegex.addressValidate();
                this.list.get(itemNum-1).setAddress(address);
                this.OutStream();
                break;
            case 6:return;
        }


    }

    /**
     * 删除指定记录
     */
    public void deleteOperation() {
        TelNoteRegex telNoteRegex =new TelNoteRegex();
        System.out.println("请输入记录的序号");
        int itemnub = telNoteRegex.menuItemValidate(1,this.list.size());
        this.list.remove(itemnub-1);
        //重新
        for (int i = 0;i<this.list.size();i++){
                this.list.get(i).setId(i+1);
            }
        this.OutStream();
        System.out.println("删除成功");
    }


    /**
     * 删除全部记录
     */
    public void deleteAllOperation() {
        this.list.clear();
        this.OutStream();
        System.out.println("您的电话本已清除");

    }

    /**
     * 按用户姓名排序记录
     */
    public void orderName() {
        Collections.sort(this.list,new OrderByName());
        for (int i =0; i<this.list.size();i++){
            this.list.get(i).setId(i+1);
        }

    }

    /**
     * 按用户年龄排序记录
     */
    public void orderAge() {
        Collections.sort(this.list,new OrderByAge());
        for (int i =0; i<this.list.size();i++) {
            this.list.get(i).setId(i + 1);
        }
    }

    /**
     * 按用户性别排序记录
     */
    public void orderSex() {
        Collections.sort(this.list, new OrderBySex());
        for (int i = 0; i < this.list.size(); i++) {
            this.list.get(i).setId(i + 1);
        }
    }



    /**
     * 排序器只能对在电话本中所存储的记录进行排序，不具备通用性，所以定义成Operatr的内部类
     * 按姓名排序的比较器
     */
    class OrderByName implements Comparator<Person> {

        @Override
        public int compare(Person o1, Person o2) {
            return o1.getName().compareTo(o2.getName());
        }
    }
    class OrderByAge implements  Comparator<Person>{

        @Override
        public int compare(Person o1, Person o2) {
            return o1.getAge().compareTo(o2.getAge());
        }
    }
    class OrderBySex implements  Comparator<Person>{

        @Override
        public int compare(Person o1, Person o2) {
            return o1.getSex().compareTo(o2.getSex());
        }
    }
    public  void OutStream(){
        ObjectOutputStream oos = null;

        try{
            oos = new ObjectOutputStream( new FileOutputStream("e:/My/存.txt"));
            for (int i =0;i<this.list.size();i++){
                oos.writeObject(this.list.get(i));
                oos.flush();
            }
        }catch (Exception e){
            e.printStackTrace();
        }finally {
            try {
                if(oos != null){
                    oos.close();
                }
            }catch (Exception e){
                e.printStackTrace();
            }
        }
    }
    public  void InStream(){
        ObjectInputStream ois = null;

        try{
            ois = new ObjectInputStream( new FileInputStream("e:/My/存.txt"));

            Person person = (Person) ois.readObject();
            System.out.println(person);

        }catch (Exception e){
            e.printStackTrace();
        }finally {
            try {
                if(ois != null){
                    ois.close();
                }
            }catch (Exception e){
                e.printStackTrace();
            }
        }
    }
}

老师这里我实现了课堂作业电话本项目实现了存取，但是在使用时会读取了TXT文件后还会判断为没有记录

 The JRE_HOME environment variable is not defined correctly This environment variable is needed to r

老师你好安装tomcat以后点击start之后cmd命令框闪退所以自己慢慢一步步用cd进入了tomcat最后报错就是上面这个，我的 jdk是1.8而tomcat是7所以不存在兼容问题那么闪退是什么原因呢

老师，我的所有貌似都没有问题，可是按了F12后查看源码，并没有所对应的文件啊

package cn.jscn.game;

import java.io.*;

public class test05 {
    public static void main(String[] args) throws IOException {
        FileInputStream fis =new FileInputStream("D:\\a.txt");
        FileOutputStream fos =new FileOutputStream("D:\\a3.txt");
        BufferedInputStream bis =new BufferedInputStream(fis);
        BufferedOutputStream bos =new BufferedOutputStream(fos);
        byte[]bs=new byte[1024];
        int len=0;
        while((len=bis.read())!=-1){
            bos.write(bs,0,len);
        }
        bis.close();
        bos.close();
    }
}

运行后不报错，但是复制后的a3文件里面没有内容，这是为什么？

老师好，为什么我这里的结果和老师的视频结果不太一样，我这里是一维数组，视频里死二维数组。

老师这两种方法run出来的结果都一样，是说明这两种方法没有区别吗

老师，我的程序就因为User类不在同一个包下就一直报错。看到下面的回答，说server和client的User类必须再同一个包下并且同名，为什么要完全一致？

老师，这里面的map.entrySet()方法返回的Set<Map.Entry<String,String>>,这个Entry是Map的内部接口，里面的getKey和getValue方法都是抽象方法，没有具体实现类，那怎么能直接调用？

这个需求用线程联合的方式是不是也可以实现

com.bjsxtjava.io.BufferedReaderjava.io.IOExceptionjava.io.InputStreamReaderjava.io.PrintWriterjava.net.InetSocketAddressjava.net.ServerSocketjava.net.Socketjava.util.ScannerSend1 Thread{
    Socket Scanner (Socket socketScanner scanner){
        .= socket.= scanner}
    () {
        .sendMsg()}
    (){
PrintWriter pw = {
            pw = PrintWriter(..getOutputStream())() {
                String msg = .nextLine()pw.println(msg)pw.flush()}
        }(Exception e){
            e.printStackTrace()}{
            (!= ) {
                .close()}
            (pw != ) {
                pw.close()}
            (.!= ) {
                {
                    ..close()} (IOException e) {
                    e.printStackTrace()}
            }
        }
    }
}
Receive1 Thread{
    Socket (Socket socket){
        .= socket}
    () {
        .receiveMsg()}
    (){
        BufferedReader br = {
            br = BufferedReader(InputStreamReader(..getInputStream()))() {
                String msg = br.readLine()System..println(+msg)}
        }(Exception e){
            e.printStackTrace()}{
            (br != ) {
                {
                    br.close()} (IOException e) {
                    e.printStackTrace()}
            }
            (.!= ) {
                {
                    ..close()} (IOException e) {
                    e.printStackTrace()}
            }
        }
    }
}
GoodTCP {
    (String[] args) {
        Scanner scanner = ServerSocket serverSocket = Socket socket = {
            scanner = Scanner(System.)System..println()String str = scanner.nextLine()String[] arr = str.split()(.equals(arr[])) {
                System..println(+arr[]+)serverSocket = ServerSocket(Integer.(arr[]))socket = serverSocket.accept()System..println()}{
                socket = Socket(arr[]Integer.(arr[]))System..println()}
            Send1(socketscanner).start()Receive1(socket).start()} (Exception e) {
            e.printStackTrace()}{
            (serverSocket != ) {
                {
                    serverSocket.close()} (IOException e) {
                    e.printStackTrace()}
            }
        }
    }
}

报错异常：

请输入：server,<port>或者：<ip>,<port>

127.0.0.1,8888

java.net.ConnectException: Connection refused: connect

at java.net.DualStackPlainSocketImpl.connect0(Native Method)

at java.net.DualStackPlainSocketImpl.socketConnect(DualStackPlainSocketImpl.java:75)

at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:476)

at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:218)

at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:200)

at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:162)

at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:394)

at java.net.Socket.connect(Socket.java:606)

at java.net.Socket.connect(Socket.java:555)

at java.net.Socket.<init>(Socket.java:451)

at java.net.Socket.<init>(Socket.java:228)

at com.bjsxt.GoodTCP.main(GoodTCP.java:129)

Process finished with exit code 0

getDeclaredConstructor(Class<?>... parameterTypes)中形参Class<?>... parameterTypes是什么意思

请问是否有Java8的中文文档

老师，视频里面说，放馒头时，满了会等待；取馒头时，没有馒头会等待。这2个条件好像永远不能同时满足吧？缓冲区只有一个，要不就是满了，要不就没有满。怎么会对生产者来说是满了，对消费者来说是空了呢？很迷糊

老师，receive的作用是等待客户端发送消息是吗？

String str=new String(dp.getData(),0,dp.getLength());是有什么作用？

dp.getData(),0,dp.getLength()分别代表了什么意思？

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.ServerSocket;
import java.net.Socket;

public class ChatRoomServer {

   //定义公共数据区
   public static String buf;
   public static void main(String[] args) {
       System.out.println("Chat  Server Version 1.0");
       System.out.println("Listen at 8888");
       try (ServerSocket ss = new ServerSocket(8888)) {

           while(true){
               Socket socket = ss.accept();
               System.out.println("连接到 "+socket.getInetAddress());
               new ChatReceive(socket).start();
               new ChatSend(socket).start();
           }
       } catch (IOException e) {
           throw new RuntimeException(e);
       }



   }
}

class ChatReceive extends Thread{
   private Socket socket;
   public ChatReceive(Socket socket){
       this.socket = socket;
   }

   @Override
   public void run() {
          doChatReceive();
   }



   public  void doChatReceive(){
        try(BufferedReader bf = new BufferedReader(new InputStreamReader(socket.getInputStream()))){
            while(true){
                String str = bf.readLine();
                synchronized ("abc"){
                    ChatRoomServer.buf = "["+socket.getInetAddress()+"]"+ str;
                    "abc".notifyAll();
                }
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
   }
}

class ChatSend extends Thread{
   private Socket socket;
   public ChatSend (Socket socket){
       this.socket = socket;
   }

   @Override
   public void run() {
       sendMsg();
   }
   private  void sendMsg() {
        try(PrintWriter pw = new PrintWriter(socket.getOutputStream())){
            while (true) {
                synchronized ("abc "){
                  //先让发送消息的线程处于等待状态
                    "abc".wait();
                    //将公共数据区中的消息发送给客户端
                    pw.println(ChatRoomServer.buf);
                    pw.flush();

                }

            }
        }catch (Exception e){
            e.printStackTrace();
        }
   }
}

老师想问一下连接后客户端一直循环输出null是什么问题呢？