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import java.io.*;
import java.util.*;

public class B322通讯录 {
    private static Map<String,people> namemap = new HashMap<>();
    private static Map<String,people> phonemap = new HashMap<>();
    private static List<people> list = new ArrayList<>();



    public static void add() throws IOException{
        Scanner scan = new Scanner(System.in);
        System.out.println("输入名字");
        String name = scan.nextLine();
        System.out.println("输入电话");
        String phone = scan.nextLine();
        System.out.println("输入地址");
        String address =scan.nextLine();
        System.out.println("输入备注");
        String mark= scan.nextLine();
        people p =new people(name,phone,address,mark);
        list.add(p);
        namemap.put(name,p);
        phonemap.put(phone,p);


        try(OutputStream os = new FileOutputStream("通讯录.txt")){

           try(ObjectOutputStream ss = new ObjectOutputStream(os)){
               ss.writeObject(list);
               ss.writeObject(namemap);
               ss.writeObject(phonemap);
           }
        }
    }

    public static void findName(){
        Scanner scanner = new Scanner(System.in);
        System.out.print("请输入姓名> ");
        String name = scanner.nextLine();

        people p = namemap.get(name);
        if (p == null) {
            System.out.println("查无此人");
        } else {
            System.out.println(p);
        }
    }
    public static void findPhone(){
        Scanner scanner = new Scanner(System.in);
        System.out.print("请输入电话> ");
        String phone = scanner.nextLine();

        people p = phonemap.get(phone);
        if (p == null) {
            System.out.println("查无此人");
        } else {
            System.out.println(p);
        }
    }


    public static void read() throws IOException,ClassNotFoundException {
        Scanner scan = new Scanner(System.in);
        File file = new File("通讯录.txt");
        if(file.exists()) {
            try (InputStream is = new FileInputStream(file)) {
                try (ObjectInputStream ois = new ObjectInputStream(is)) {
                    list = (List<people>) ois.readObject();
                    namemap = (Map<String, people>) ois.readObject();
                    phonemap = (Map<String, people>) ois.readObject();
                    System.out.println(list);

                }
            }
        }
        scan.nextLine();
    }

    public static void main(String[] args) throws IOException, ClassNotFoundException {


        File file = new File("通讯录.txt");
        if(!file.exists()){
            file.createNewFile();
        }

       /* if(file.exists()){
            try(InputStream is = new FileInputStream(file)){
                try(ObjectInputStream ois = new ObjectInputStream(is)){
                    list = (List<people>) ois.readObject();
                    namemap = (Map<String, people>) ois.readObject();
                    phonemap = (Map<String, people>) ois.readObject();
                }
            }
        }*/

        Scanner scan = new Scanner(System.in);
        while(true){
            System.out.println("选择你想要的功能");
            System.out.println("1.添加");
            System.out.println("2.名字找人");
            System.out.println("3.电话找人");
            System.out.println("4.显示当前所有人的名单");
            System.out.println("5.清空通讯录");
            int n = scan.nextInt();
            if(n==1){
                add();
            }
            if(n==2){
                findName();
            }if(n==3){
                findPhone();
            }if(n==4){
                read();
            }if(n==5){
                list.clear();//当顺序表清除后。如果要继续调用4方法，仍然会打印，这表示数据被记录在了文件中。
            }
            scan.nextLine();
        }
    }


}


//=============================================================
 class people implements Serializable {

    String name;

    String number;

    String address;

    String mark;

     public people(String name, String number, String address, String mark) {
         this.name = name;
         this.number = number;
         this.address = address;
         this.mark = mark;
     }

     public people() {
         super();
     }

     @Override
     public int hashCode() {
         return super.hashCode();
     }

     @Override
     public boolean equals(Object obj) {
         return super.equals(obj);
     }

     @Override
     protected Object clone() throws CloneNotSupportedException {
         return super.clone();
     }

     @Override
     protected void finalize() throws Throwable {
         super.finalize();
     }

     @Override
     public String toString() {
         return "people{" +
                 "name='" + name + '\'' +
                 ", number='" + number + '\'' +
                 ", address='" + address + '\'' +
                 ", mark='" + mark + '\'' +
                 '}'+'\n';
     }
  }

En el caso de una ruta absoluta, con el fin de evitar que InvalidClassException cuando deserialización (tipos de excepción no válido), es necesario establecer el serialVersionUID idea generada automáticamente (versión de la serie Id), en la fijación de idea de -Inspecciones (ajuste) (revisión) ----- serialización hay dos opciones palabra UID (número de serie) en cuestiones