完整代码：1.客户类（class person）：package客户管理系统;public class Person {private int num;private String name;private String address;private String sex;public Person(){}public Person(int num,String name,String address,String sex){this.num=num;=name;this.address=address;this.sex=sex;}public void setNum(int num){this.num=num;}public int getNum(){return num;}public void setName(String name){=name;}public String getName(){return name;}public void setAddress(String address){this.address=address;}public String getAddress(){return address;}public void setSex(String sex){this.sex=sex;}public String getSex(){return sex;}public String toString() {return"\t"+num+"\t"+name+"\t"+address+"\t"+sex;}}2.菜单类(class Menu)：package客户管理系统;import java.util.Scanner;public class Menu {Scanner input=new Scanner(System.in);public Menu() {}public int showMenu() {System.out.println("***********************************" );System.out.println("客户管理系统");System.out.println("===================================" );System.out.println("【1】增加");System.out.println("【2】删除");System.out.println("【3】修改");System.out.println("【4】查询");System.out.println("【5】浏览");System.out.println("【6】退出");System.out.println("***********************************" );System.out.print("请选择操作：");return input.nextInt();}public int subMenu() {System.out.println("\t【查询客户】");System.out.println("\t[1]按客户编号查询");System.out.println("\t[2]按客户姓名查询");System.out.println("\t[3]按地址查询");System.out.println("\t[4]退出");System.out.println("\t请选择查询编号");return input.nextInt();}}3.实际操作类（class FileOperate ）：package客户管理系统;import java.io.BufferedReader;import java.io.File;import java.io.FileNotFoundException;import java.io.FileReader;import java.io.IOException;import java.io.PrintWriter;import java.util.ArrayList;import java.util.List;import java.util.Scanner;public class FileOperate {private static String INFO="D:/info.dat"; File file = new File(INFO);Scanner input=new Scanner(System.in);public FileOperate() {if (!file.exists()) {try {file.createNewFile();}catch(IOException e) {e.printStackTrace();}}}public List<Person> getList() throws NumberFormatException,IOException{BufferedReader br=new BufferedReader(newFileReader(file));String msg=null;List<Person> list =new ArrayList<Person>();while ((msg =br.readLine())!=null) {String arr[]=msg.split("\t");int num=Integer.parseInt(arr[0]);String name =arr[1];String address=arr[2];String sex=arr[3];Person person =new Person(num,name,address,sex);list.add(person);}br.close();return list;}private void savelist(List<Person> list)throws FileNotFoundException{PrintWriter pw=new PrintWriter(new File(INFO));for (Person c:list) {pw.format("%d\t %s\t %s\t %s\t\r\n",c.getNum(),c.getName(),c.getAddress(),c.getSex());}pw.close();}public int getper(int num) throws NumberFormatException,IOException{List<Person> list=getList();for (int i=0;i<list.size();i++) {Person per=list.get(i);if(num==per.getNum()) {return i;}}return -1;}//增加public void insert() throwsNumberFormatException,IOException{System.out.println("请输入编号：");int num=input.nextInt();int index=getper(num);if (index!=-1) {System.out.println("此编号已存在！");}else{System.out.println("请输入姓名：");String name=input.next();System.out.println("请输入地址：");String address=input.next();System.out.println("请输入性别：");String sex=input.next();Person person=new Person(num,name,address,sex);List<Person> list=getList();list.add(person);savelist(list);System.out.println("新增成功！");}}//删除public void delete() throws NumberFormatException,IOException{System.out.println("请输入要删除的编号：");int num=input.nextInt();List<Person> list=getList();boolean flag=false;for(int i=0;i<list.size();i++) {Person per=list.get(i);if(num==per.getNum()) {showTitle();System.out.println(per);System.out.println("是否确定删除（Y/N）？");String answer=input.next();if("Y".equalsIgnoreCase(answer)) {list.remove(i);savelist(list);System.out.println("删除成功!");}flag=true;break;}}if (!flag) {System.out.println("该客户不存在！");}}//修改public void update() throws NumberFormatException,IOException{shoAll();System.out.println("请输入编号：\n");int num=input.nextInt();int Id=getper(num);if (Id!=-1) {System.out.println("请输入姓名:");String name=input.next();System.out.println("请输入地址:");String address=input.next();System.out.println("请输入性别:");String sex=input.next();List<Person>list=getList();Person per=list.get(Id);per.setName(name);per.setAddress(address);per.setSex(sex);showTitle();System.out.println(per);savelist(list);System.out.println("修改成功！");}else {System.out.println("编号不存在！");}}//查询public void search() throws NumberFormatException,IOException{boolean flag=true;List<Person>list=getList();if(list.size()!=0) {while(flag) {int slt=new Menu().subMenu();switch (slt) {case 1:System.out.print("\t请输入编号：");findId(input.nextInt());break;case 2:System.out.print("\t请输入姓名：");findName(input.next());break;case 3:System.out.print("\t请输入地址：");findAddress(input.next());break;case 4:flag=quit();break;}}}else {System.out.println("无任何信息！");}}//按编号查询public void findId(int num) throws NumberFormatException,IOException{List<Person>list=getList();boolean flag=false;for (int i=0;i<list.size();i++) {Person per =list.get(i);if(num==per.getNum()) {showTitle();System.out.println(per);flag=true;break;}}if (!flag) {System.out.println("\t该客户不存在！");}}//按姓名查询public void findName(String name) throws NumberFormatException,IOException{List<Person>list=getList();boolean flag=false;for (int i=0;i<list.size();i++) {Person per =list.get(i);if(name.equals(per.getName())) {showTitle();System.out.println(per);flag=true;break;}}if (!flag) {System.out.println("\t该客户不存在！");}}//按地址查找public void findAddress(String address) throws NumberFormatException,IOException{List<Person>list=getList();boolean flag=false;for (int i=0;i<list.size();i++) {Person per =list.get(i);if(address.equals(per.getAddress())) {showTitle();flag=true;System.out.println(per);break;}}if (!flag) {System.out.println("\t该客户不存在！");}}//退出查询public boolean quit() {System.out.println("是否确定退出（Y/N）？");if ("Y".equalsIgnoreCase(input.next())) {System.out.println("退出成功！");return false;}else {return true;}}//浏览public void shoAll() throwsNumberFormatException,IOException{List<Person>list=getList();if (list.size()!=0) {showTitle();for (Person person:list) {System.out.println(person.toString());}}else {System.out.println("无任何信息！");}}public void showTitle() {System.out.println("客户信息为：\n\t编号\t姓名\t地址\t性别");}//退出系统public boolean exit() {System.out.println("是否确定退出（Y/N）？");return!"Y".equalsIgnoreCase(input.next())?true:false;}}4.测试类（class Text）:package客户管理系统;import java.io.IOException;public class Test {public static void main(String[] args) throws NumberFormatException,IOException {Menu m=new Menu();boolean flag=true;FileOperate fo=new FileOperate();while(flag) {int slt=m.showMenu();switch(slt) {case 1:fo.insert();//增加break;case 2:fo.delete();//删除break;case 3:fo.update();//修改break;case 4:fo.search();//查询break;case 5:fo.shoAll();//浏览break;case 6: //退出flag=fo.exit();if(!flag)System.out.println("谢谢使用！");break;}}}}。