【高级Java】高级Java实验
一、反射与动态代理
1、（4分）请通过反射技术，为附件中的Person.class生成相应的.java代码，java代码中的方法的方法体为空，即方法内部代码不用生成。请注意生成的java代码的格式。
2、（3分）请为第1题中Person类创建代理类 PersonProxy，PersonProxy的在代理Person类的所有setter方法时，把方法的调用时间、方法名称写入到文本文件中，每一行日志的格式为：
* 时间：2012-09-01 23：34：24;方法名称：setName;参数：张小平
3、（3分）请用动态代理技术完成第2题
1.1 experiment1
public class Person implements Speakable {private String name;//学生姓名private String Gender;//性别private String id;//身份证号private String tel;//电话public Person() {}public Person(String name, String Gender, String id, String tel) {this.name = name;this.Gender = Gender;this.id = id;this.tel = tel;}public String getName() {return name;}public void setName(String name) {this.name = name;}public String getGender() {return Gender;}public void setGender(String Gender) {this.Gender = Gender;}public String getId() {return id;}public void setId(String id) {this.id = id;}public String getTel() {return tel;}public void setTel(String tel) {this.tel = tel;}@Overridepublic String toString() {return "PersonRefection{" +"name='" + name + '\'' +", sex='" + Gender + '\'' +", id='" + id + '\'' +", tel='" + tel + '\'' +'}';}@Overridepublic void speak(String message) {System.out.println(message);}
}
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.lang.reflect.*;public class PersonRefection {static String pathName = "E:\\学习\\代码\\AdvancedJAVA\\src\\homework2\\experiment2\\Person.java";static FileOutputStream fos;static {try {fos = new FileOutputStream(pathName);} catch (FileNotFoundException e) {e.printStackTrace();}}static Class clazz;static {try {clazz = Class.forName("Person");fos = new FileOutputStream(pathName);} catch (ClassNotFoundException | FileNotFoundException e) {e.printStackTrace();}}public static void getPackage(String pathName) {String packageName = clazz.getPackage().getName();String writePackage = "package " + packageName + ";\n\n";try {fos.write(writePackage.getBytes());} catch (IOException e) {e.printStackTrace();}}public static void main(final String[] args) throws NoSuchMethodException, IOException, ClassNotFoundException, InvocationTargetException, InstantiationException, IllegalAccessException {String pathName = "E:\\学习\\代码\\AdvancedJAVA\\src\\homework2\\experiment2\\Person.java";FileOutputStream fos = new FileOutputStream(pathName);Class clazz = Class.forName("Person");//获取类所在的包名String packageName = clazz.getPackage().getName();String writePackage = "package " + packageName + ";\n\n";fos.write(writePackage.getBytes());//获取类中的权限修饰符及类名并输出String modifier = Modifier.toString(clazz.getModifiers());String className = clazz.getSimpleName();String writeClass = modifier + " class " + className + " {\n";fos.write(writeClass.getBytes());//获取类中所有的字段Field[] fieldArray = clazz.getDeclaredFields();for (Field f : fieldArray) {String mod = Modifier.toString(f.getModifiers());String type = f.getType().getSimpleName();String name = f.getName();String writeField = "\t" + mod + " " + type + " " + name + ";\n";fos.write(writeField.getBytes());}fos.write("\n".getBytes());//获取类中所有的构造方法Constructor[] constructorArray = clazz.getConstructors();for (Constructor c : constructorArray) {String mod = Modifier.toString(c.getModifiers());String writeConstructor = "\t" + mod + " " + className + "(";//获取构造方法里面所有的参数Class[] prams = c.getParameterTypes();int count = 0;for (Class cl : prams) {String pramName = cl.getSimpleName();writeConstructor += pramName + " args" + count;if (count < prams.length - 1) {writeConstructor += ", ";}count++;}writeConstructor += ") {}\n";fos.write(writeConstructor.getBytes());}fos.write("\n".getBytes());//获取类中所有的方法Method[] methodArray = clazz.getDeclaredMethods();for (Method m : methodArray) {String mod = Modifier.toString(m.getModifiers());String type = m.getReturnType().getSimpleName();String name = m.getName();String writeMethod = "\t" + mod + " " + type + " " + name + "(";//与构造方法一样，获取方法里面所有的参数Class[] prams = m.getParameterTypes();int count = 0;for (Class cl : prams) {String pramName = cl.getSimpleName();writeMethod += pramName + " args" + count;if (count < prams.length - 1) {writeMethod += ", ";}count++;}writeMethod += ") {\n";if (type.equals("int") || type.equals("double")) {writeMethod += "\t\treturn 0;\n";} else if (type.equals("boolean")) {writeMethod += "\t\treturn false;\n";} else if (type.equals("void")) {writeMethod += "";} else {writeMethod += "\t\treturn null;\n";}writeMethod += "\t}\n\n";fos.write(writeMethod.getBytes());}fos.write("}".getBytes());}
}
import java.io.IOException;public interface Speakable {public void speak(String message);public void setName(String args0) throws IOException;public void setTel(String args0) throws IOException;public void setGender(String args0) throws IOException;public void setId(String args0) throws IOException;
}
1.2 experiment2
import homework2.experiment1.Person;import java.io.IOException;public class Bootstrap {public static void main(final String[] args) throws IOException {Person person = new Person();PersonProxy personProxy = new PersonProxy(person);personProxy.setId("123");personProxy.setName("魏乐天");}
}public class Person {private String name;private String Gender;private String id;private String tel;public Person() {}public Person(String args0, String args1, String args2, String args3) {}public String toString() {return null;}public String getName() {return null;}public void setName(String args0) {}public String getId() {return null;}public void setGender(String args0) {}public String getTel() {return null;}public void speak(String args0) {}public void setTel(String args0) {}public String getGender() {return null;}public void setId(String args0) {}}import homework2.experiment1.Person;
import homework2.experiment1.Speakable;import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.util.Calendar;//2、（3分）请为第1题中Person类创建代理类 PersonProxy，PersonProxy的在代理Person类的所有setter方法时，把方法的调用时间、方法名称写入到文本文件中，每一行日志的格式为：
// 时间：2012-09-01 23：34：24;方法名称：setName;参数：张小平
public class PersonProxy implements Speakable {Person person;File file = new File("E:\\学习\\代码\\AdvancedJAVA\\src\\homework2\\experiment2\\Log");public PersonProxy(Person person) {this.person = person;}@Overridepublic void speak(String message) {}public void setName(String name) throws IOException {WriteToText(file, "setName", name);this.person.setName(name);}public void setGender(String Gender) throws IOException {WriteToText(file, "setGender", Gender);this.person.setGender(Gender);}public void setId(String id) throws IOException {WriteToText(file, "setId", id);this.person.setId(id);}public void setTel(String tel) throws IOException {WriteToText(file, "setTel", tel);this.person.setTel(tel);}public void WriteToText(File file, String MethodName, String parameter) throws IOException {//如果文件不存在,就动态创建文件if (!file.exists()) {file.createNewFile();}FileWriter fw = null;final String writeDate = "时间:" + this.get_nowDate() + ";" + "方法名称:" + MethodName + ";参数:" + parameter;try {//设置为:True,表示写入的时候追加数据fw = new FileWriter(file, true);//回车并换行fw.write(writeDate + "\r\n");} catch (final IOException e) {e.printStackTrace();} finally {if (fw != null) {fw.close();}}}private String get_nowDate() {Calendar D = Calendar.getInstance();int year = 0;int moth = 0;int day = 0;int hour = 0;int minute = 0;int second = 0;year = D.get(Calendar.YEAR);moth = D.get(Calendar.MONTH) + 1;day = D.get(Calendar.DAY_OF_MONTH);hour = D.get(Calendar.HOUR_OF_DAY);minute = D.get(Calendar.MINUTE);second = D.get(Calendar.SECOND);String now_date = String.valueOf(year) + "-" + String.valueOf(moth)+ "-" + String.valueOf(day) + " " + String.valueOf(hour) + ":"+ String.valueOf(minute) + ":" + String.valueOf(second);return now_date;}}
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.lang.reflect.Constructor;
import java.lang.reflect.Field;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;public class PersonRefection {static String pathName = "E:\\学习\\代码\\AdvancedJAVA\\src\\homework2\\experiment2\\Person.java";static FileOutputStream fos;static {try {fos = new FileOutputStream(pathName);} catch (FileNotFoundException e) {e.printStackTrace();}}public static void main(String[] args) throws IOException, ClassNotFoundException {getPackage();getClazz();getField();getConstructor();getMethod();}/*** 获取包名*/public static void getPackage() throws ClassNotFoundException, FileNotFoundException {String pathName = "E:\\学习\\代码\\AdvancedJAVA\\src\\homework2\\experiment2\\Person.java";Class<?> clazz = Class.forName("homework2.experiment2.Person");String packageName = clazz.getPackage().getName();String writePackage = "package " + packageName + ";\n\n";try {fos.write(writePackage.getBytes());} catch (IOException e) {e.printStackTrace();}}/*** 获取类中的权限修饰符及类名并输出*/public static void getClazz() throws IOException, ClassNotFoundException {String pathName = "E:\\学习\\代码\\AdvancedJAVA\\src\\homework2\\experiment2\\Person.java";Class<?> clazz = Class.forName("homework2.experiment2.Person");String modifier = Modifier.toString(clazz.getModifiers());String className = clazz.getSimpleName();String writeClass = modifier + " class " + className + " {\n";fos.write(writeClass.getBytes());}/*** 获取类中所有的字段*/public static void getField() throws IOException, ClassNotFoundException {String pathName = "E:\\学习\\代码\\AdvancedJAVA\\src\\homework2\\experiment2\\Person.java";Class<?> clazz = Class.forName("homework2.experiment2.Person");Field[] fieldArray = clazz.getDeclaredFields();for (Field f : fieldArray) {String mod = Modifier.toString(f.getModifiers());String type = f.getType().getSimpleName();String name = f.getName();String writeField = "\t" + mod + " " + type + " " + name + ";\n";fos.write(writeField.getBytes());}fos.write("\n".getBytes());}/*** 获取类中所有的构造方法*/public static void getConstructor() throws IOException, ClassNotFoundException {String pathName = "E:\\学习\\代码\\AdvancedJAVA\\src\\homework2\\experiment2\\Person.java";Class<?> clazz = Class.forName("homework2.experiment2.Person");String className = clazz.getSimpleName();Constructor[] constructorArray = clazz.getConstructors();for (Constructor c : constructorArray) {String mod = Modifier.toString(c.getModifiers());String writeConstructor = "\t" + mod + " " + className + "(";//获取构造方法里面所有的参数Class[] prams = c.getParameterTypes();int count = 0;for (Class cl : prams) {String pramName = cl.getSimpleName();writeConstructor += pramName + " args" + count;if (count < prams.length - 1) {writeConstructor += ", ";}count++;}writeConstructor += ") {}\n";fos.write(writeConstructor.getBytes());}fos.write("\n".getBytes());}/*** 获取类中所有的方法*/public static void getMethod() throws IOException, ClassNotFoundException {String pathName = "E:\\学习\\代码\\AdvancedJAVA\\src\\homework2\\experiment2\\Person.java";Class<?> clazz = Class.forName("homework2.experiment2.Person");Method[] methodArray = clazz.getDeclaredMethods();for (Method m : methodArray) {String mod = Modifier.toString(m.getModifiers());String type = m.getReturnType().getSimpleName();String name = m.getName();String writeMethod = "\t" + mod + " " + type + " " + name + "(";//与构造方法一样，获取方法里面所有的参数Class[] prams = m.getParameterTypes();int count = 0;for (Class cl : prams) {String pramName = cl.getSimpleName();writeMethod += pramName + " args" + count;if (count < prams.length - 1) {writeMethod += ", ";}count++;}writeMethod += ") {\n";switch (type) {case "int":case "double":writeMethod += "\t\treturn 0;\n";break;case "boolean":writeMethod += "\t\treturn false;\n";break;case "void":writeMethod += "";break;default:writeMethod += "\t\treturn null;\n";break;}writeMethod += "\t}\n\n";fos.write(writeMethod.getBytes());}fos.write("}".getBytes());}}1.3 experiment3
import homework2.experiment1.Speakable;import java.io.IOException;
import java.lang.reflect.Proxy;public class BootStrap {public static void main(final String[] args) throws IOException {//创建一个真实对象Person person = new Person();//创建一个动态代理对象MyProxy myProxy = new MyProxy(person);//获取被代理类的CLassLoader对象ClassLoader loader = person.getClass().getClassLoader();//动态构造一个代理对象Speakable speakable = (Speakable) Proxy.newProxyInstance(loader,new Class[]{Speakable.class},//接口对象数组，表示我们要给代理对象提供一个怎样的接口，如果提供了这样一组接口数组，就是声明了代理类实现了这些接口，代理类就可以调用接口中声明的所有方法。myProxy);speakable.setGender("man");}
}
import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.lang.reflect.InvocationHandler;
import java.lang.reflect.Method;
import java.util.Calendar;public class MyProxy implements InvocationHandler {File file = new File("E:\\学习\\代码\\AdvancedJAVA\\src\\homework2\\experiment3\\Log");private Object proxied;public MyProxy(Object proxied) {this.proxied = proxied;}@Overridepublic Object invoke(Object proxy, Method method, Object[] args) throws Throwable {//proxy:代理类代理的真实代理对象//method：我们要调用某个对象真实的方法的Method对象//args:代理对象方法传递的参数WriteToText(file, method.getName(), (String) args[0]);method.invoke(this.proxied, args);return null;}public void WriteToText(File file, String MethodName, String parameter) throws IOException {//如果文件不存在,就动态创建文件if (!file.exists()) {file.createNewFile();}FileWriter fw = null;String writeDate = "时间:" + this.get_nowDate() + ";" + "方法名称:" + MethodName + ";参数:" + parameter;try {//设置为:True,表示写入的时候追加数据fw = new FileWriter(file, true);//回车并换行fw.write(writeDate + "\r\n");} catch (IOException e) {e.printStackTrace();} finally {if (fw != null) {fw.close();}}}private String get_nowDate() {Calendar D = Calendar.getInstance();int year = 0;int moth = 0;int day = 0;int hour = 0;int minute = 0;int second = 0;year = D.get(Calendar.YEAR);moth = D.get(Calendar.MONTH) + 1;day = D.get(Calendar.DAY_OF_MONTH);hour = D.get(Calendar.HOUR_OF_DAY);minute = D.get(Calendar.MINUTE);second = D.get(Calendar.SECOND);String now_date = String.valueOf(year) + "-" + String.valueOf(moth)+ "-" + String.valueOf(day) + " " + String.valueOf(hour) + ":"+ String.valueOf(minute) + ":" + String.valueOf(second);return now_date;}
}
public class Person implements Speakable {private String name;private String Gender;private String id;private String tel;public Person() {}public Person(String args0, String args1, String args2, String args3) {}public String toString() {return null;}public String getName() {return null;}public void setName(String args0) {}public String getId() {return null;}public void setGender(String args0) {}public String getTel() {return null;}public void speak(String args0) {}public void setTel(String args0) {}public String getGender() {return null;}public void setId(String args0) {}}import java.io.IOException;public interface Speakable {public void speak(String message);public void setName(String args0) throws IOException;public void setTel(String args0) throws IOException;public void setGender(String args0) throws IOException;public void setId(String args0) throws IOException;
}
二、基于数据库的学生管理系统
1、请编程实现基于数据库的学生信息管理程序，程序的功能有：显示所有学生、新增学生、删除学生、修改学生、查找学生（根据学号、姓名、班级、性别、专业、学院等），程序采用命令行方式。
2、请编程实现把从数据库中查询出的学生信息记录集（ResultSet）中的记录转换为学生对象。
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.Statement;//1、请编程实现基于数据库的学生信息管理程序，程序的功能有：显示所有学生、新增学生、删除学生、修改学生、查找学生（根据学号、姓名、班级、性别、专业、学院等），程序采用命令行方式。
// 2、请编程实现把从数据库中查询出的学生信息记录集（ResultSet）中的记录转换为学生对象。/*** 建立与数据库之间的连接会话，所有的操作都是基于这个会话基础上进行的*/
public class MySqlDAO {public static Connection getConnection() throws Exception {String driverName = "com.mysql.cj.jdbc.Driver"; //驱动名称String url = "jdbc:mysql://localhost:3306/student"; //连接字符串String username = "root"; //用户名String password = "lele20011019"; //密码Class.forName(driverName); //加载数据库的驱动，驱动程序自动调用DriverManger中方法将自身注册到管理器中return DriverManager.getConnection(url, username, password);}/*** 获取Statement对象，通过Statement执行SQL语句** @return* @throws Exception*/public static Statement getStatement() throws Exception {return getConnection().createStatement();}/*** 获取PreparedStatement对象，通过PreparedStatement执行SQL语句** @param sql* @return* @throws Exception*/public static PreparedStatement preparedStatement(String sql) throws Exception {return getConnection().prepareStatement(sql);}public static void connectionClose() throws Exception {getConnection().close();}
}
public class Student {private int Id; //学号private String Name; //姓名private String Gender; //性别private String college; //学院private String Major; //专业private int Clazz; //班级public Student() {}public Student(int id, String name, String gender, String college, String major, int Clazz) {this.Id = id;this.Name = name;this.Gender = gender;this.college = college;this.Major = major;this.Clazz = Clazz;}public int getId() {return Id;}public void setId(int id) {this.Id = id;}public String getName() {return Name;}public void setName(String name) {this.Name = name;}public String getGender() {return Gender;}public void setGender(String gender) {if (gender.equals("男") || gender.equals("女")) {this.Gender = gender;} else {try {throw new IllegalAccessException("性别只能为男或女");} catch (IllegalAccessException E) {E.printStackTrace();}}}public String getCollege() {return college;}public void setCollege(String college) {this.college = college;}public String getMajor() {return Major;}public void setMajor(String major) {this.Major = major;}public int getClazz() {return Clazz;}public void setClass(int Clazz) {this.Clazz = Clazz;}
}
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;
import java.util.Scanner;import static homework3.MySqlDAO.connectionClose;public class StudentManagementSystem {static Scanner input = new Scanner(System.in);static ResultSet rs = null;public static void main(String[] args) throws Exception {
// Student student1 = new Student(1, "魏乐天", "男", "两江人工智能学院", "软件工程", 2);
// Student student2 = new Student(2, "茹祎龙", "男", "两江人工智能学院", "软件工程", 2);
// Student student3 = new Student(3, "宋梦洋", "男", "两江人工智能学院", "软件工程", 2);
// Student student4 = new Student(4, "边帝行", "男", "两江人工智能学院", "软件工程", 2);
// Student student5 = new Student(5, "张毅敏", "男", "电子与电气工程学院", "自动化", 1);startSystem();}public static void startSystem() throws Exception {while (true) {int choice;System.out.println("学生管理系统");System.out.println("请选择所需功能");System.out.println("1.创建学生信息");System.out.println("2.删除学生信息");System.out.println("3.修改学生信息");System.out.println("4.查询学生信息");System.out.println("5.退出");choice = input.nextInt();if (choice == 1) {createStudent();} else if (choice == 2) {while (true) {System.out.println("请输入要删除学生的学号(输入-1退出)：");int no = input.nextInt();if (no == -1)break;deleteStudent(no);}} else if (choice == 3) {while (true) {System.out.println("输入要修改学生的学号，如果学号不存在则创建(输入-1退出)");int no = input.nextInt();if (no == -1)break;updateStudent(no);}} else if (choice == 4) {int choice1;while (true) {System.out.println("请输入查询的方式");System.out.println("1.通过学号查询");System.out.println("2.通过姓名查询");System.out.println("3.通过性别查询");System.out.println("4.通过学院查询");System.out.println("5.通过专业查询");System.out.println("6.通过班级查询");System.out.println("7.退出");choice1 = input.nextInt();if (choice1 == 1) {System.out.println("请输入学号：");int xuehao = input.nextInt();selectStudentById(xuehao);} else if (choice1 == 2) {System.out.println("请输姓名：");String name1 = input.next();selectStudentByName(name1);} else if (choice1 == 3) {System.out.println("请输入性别：");String gender1 = input.next();selectStudentByGender(gender1);} else if (choice1 == 4) {System.out.println("请输入学院：");String college1 = input.next();selectStudentByCollege(college1);} else if (choice1 == 5) {System.out.println("请输入专业：");String major1 = input.next();selectStudentByMajor(major1);} else if (choice1 == 6) {System.out.println("请输入班级：");int class1 = input.nextInt();selectStudentByClass(class1);} else {break;}}} else {break;}}}public static void createStudent() throws Exception {System.out.println("请输入你想创建的学生的信息(输入-1退出)：");int no, clazz;String name, gender, college, major;while (true) {System.out.println("学号：");no = input.nextInt();if (no == -1)break;System.out.println("姓名：");name = input.next();if (name.equals("-1"))break;System.out.println("性别：");gender = input.next();if (gender.equals("-1"))break;System.out.println("学院：");college = input.next();if (college.equals("-1"))break;System.out.println("专业：");major = input.next();if (major.equals("-1"))break;System.out.println("班级：");clazz = input.nextInt();if (clazz == -1)break;Student newStudent = new Student(no, name, gender, college, major, clazz);insertStudent(newStudent);}}public static boolean tableNameExist(String tableName) throws Exception {String sql = "select TABLE_NAME from INFORMATION_SCHEMA.TABLES where TABLE_SCHEMA='student' and TABLE_NAME='" + tableName + "'";PreparedStatement ps = MySqlDAO.preparedStatement(sql);ps.execute();ResultSet rs = ps.executeQuery();rs.close();ps.close();connectionClose();return rs.next();}/*** 建表*/public static void createTable(String tableName) throws Exception {String sql = "create table " + tableName + "(No int primary key, name char(20),gender char(4),college char(100),major char(100),Class int)";if (!tableNameExist(tableName)) {PreparedStatement ps = MySqlDAO.preparedStatement(sql);ps.execute();ps.close();} else {try {throw new Exception("该表已经存在");} catch (Exception E) {E.printStackTrace();}}}/*** 插入学生信息*/public static void insertStudent(Student student) throws Exception {String sql = "insert into student values(?,?,?,?,?,?)";PreparedStatement ps = MySqlDAO.preparedStatement(sql);ps.setInt(1, student.getId());ps.setString(2, student.getName());ps.setString(3, student.getGender());ps.setString(4, student.getCollege());ps.setString(5, student.getMajor());ps.setInt(6, student.getClazz());ps.execute();ps.close();connectionClose();}/*** 删除学生信息*/public static void deleteStudent(int no) throws Exception {String sql = "delete from student where No=?";PreparedStatement ps = MySqlDAO.preparedStatement(sql);ps.setInt(1, no);ps.execute();ps.close();connectionClose();}/*** 更新学生信息*/public static void updateStudent(int no) throws Exception {int clazz;String name, gender, college, major;deleteStudent(no);System.out.println("姓名：");name = input.next();System.out.println("性别：");gender = input.next();System.out.println("学院：");college = input.next();System.out.println("专业：");major = input.next();System.out.println("班级：");clazz = input.nextInt();Student newStudent = new Student(no, name, gender, college, major, clazz);insertStudent(newStudent);}/*** 打印学生信息*/public static void printInformation(ResultSet rs) throws SQLException {while (rs.next()) {System.out.println("id: " + rs.getInt("no"));System.out.println("name: " + rs.getString("name"));System.out.println("gender: " + rs.getString("gender"));System.out.println("college: " + rs.getString("college"));System.out.println("major: " + rs.getString("major"));System.out.println("class: " + rs.getInt("class"));System.out.println();}}public static void executeToRs(PreparedStatement ps) throws Exception {rs = ps.executeQuery();ps.close();connectionClose();}/*** 通过id查询学生信息*/public static void selectStudentById(int id) throws Exception {String sql = "select * from student where no = " + id;PreparedStatement ps = MySqlDAO.preparedStatement(sql);executeToRs(ps);printInformation(rs);ps.close();connectionClose();}/*** 通过name查询学生信息*/public static void selectStudentByName(String name) throws Exception {String sql = "select * from student where name = " + name;PreparedStatement ps = MySqlDAO.preparedStatement(sql);executeToRs(ps);printInformation(rs);ps.close();connectionClose();}/*** 通过性别查询学生信息*/public static void selectStudentByGender(String gender) throws Exception {String sql = "select * from student where gender = " + gender;PreparedStatement ps = MySqlDAO.preparedStatement(sql);executeToRs(ps);printInformation(rs);ps.close();connectionClose();}/*** 通过学院查询学生信息*/public static void selectStudentByCollege(String college) throws Exception {String sql = "select * from student where college = " + college;PreparedStatement ps = MySqlDAO.preparedStatement(sql);executeToRs(ps);printInformation(rs);ps.close();connectionClose();}/*** 通过专业查询学生信息*/public static void selectStudentByMajor(String major) throws Exception {String sql = "select * from student where major = " + major;PreparedStatement ps = MySqlDAO.preparedStatement(sql);executeToRs(ps);printInformation(rs);ps.close();connectionClose();}/*** 通过班级查询学生信息*/public static void selectStudentByClass(int clazz) throws Exception {String sql = "select * from student where class = " + clazz;PreparedStatement ps = MySqlDAO.preparedStatement(sql);executeToRs(ps);printInformation(rs);ps.close();connectionClose();}public static void rsToObject(ResultSet rs) throws SQLException {List<Student> students = new ArrayList<>();while (rs.next()) {int no = rs.getInt("no");String name = rs.getString("name");String gender = rs.getString("gender");String college = rs.getString("college");String major = rs.getString("major");int clazz = rs.getInt("class");students.add(new Student(no, name, gender, college, major, clazz));}}}
三、注解、
3.1 experiment1
1.创建Person类，Person的属性有：
* String name 姓名
* String sex 性别
* Integer age 年龄,
* String idNo 身份证号
* Boolean isMarried 是否已婚
* 请生成相应的getter、setter方法。请编写注解@Label，表示所注解对象的中文名称，√
* 请把@Label注解标注在Person类和Person的每个属性上面。√
* 请编写PersonInput类，负责提示录入人员的相关属性，提示必须是注解@Label所标注的中文名称。√
* 请编写PersonDisplay，负责显示人员信息，显示时的属性名称必须为注解@Label所标注的中文名称√，
* PersonInput类与PersonDisplay类实现了共同的接口PersonAction，接口PersonAction有方法process，方法process的签名为：public Person process(Person person);√
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;@Target({ElementType.FIELD, ElementType.TYPE})
@Retention(RetentionPolicy.RUNTIME)
public @interface Label {String value();
}
//注解处理器接口
public interface PersonAction {public Person process(Person person) throws IllegalAccessException;
}
public class Person {@Label("姓名")String name; //姓名@Label("性别")String sex; //性别@Label("年龄")Integer age; //年龄@Label("身份证号")String idNo; //身份证号@Label("是否已婚")Boolean isMarried; //是否已婚public Person() {}public Person(String name, String sex, Integer age, String idNo, boolean isMarried) {this.name = name;this.sex = sex;this.age = age;this.idNo = idNo;this.isMarried = isMarried;}public String getName() {return name;}public void setName(String name) {this.name = name;}public String getSex() {return sex;}public void setSex(String sex) {this.sex = sex;}public Integer getAge() {return age;}public void setAge(Integer age) {this.age = age;}public String getIdNo() {return idNo;}public void setIdNo(String idNo) {this.idNo = idNo;}public Boolean isMarried() {return isMarried;}public void setMarried(Boolean married) {isMarried = married;}
}
import java.lang.reflect.Field;/*** 负责显示人员信息，显示时的属性名称必须为注解@Label所标注的中文名称，*/
public class PersonDisplay implements PersonAction {@Overridepublic Person process(Person person) throws IllegalAccessException {Class clazz = person.getClass();Field[] fields = clazz.getDeclaredFields();for (Field field : fields) {//获取Label注解的value值if (field.isAnnotationPresent(Label.class)) {String name = field.getAnnotation(Label.class).value();System.out.print(name + ":");}//获取属性的值Object obj = field.get(person);System.out.println(obj);}return person;}
}
import java.lang.reflect.Field;
import java.util.Scanner;/*** 负责提示录入人员的相关属性，提示必须是注解@Label所标注的中文名称。*/
public class PersonInput implements PersonAction {@Overridepublic Person process(Person person) throws IllegalAccessException {Scanner input = new Scanner(System.in);Class clazz = person.getClass();//获取Class对象Field[] fields = clazz.getDeclaredFields();//通过Class对象获取Field对象//遍历获取的person对象的所有字段for (Field field : fields) {Object obj = field.get(person);if (obj == null) {String s = field.getAnnotation(Label.class).value();System.out.print("请输入" + s + ":");String s1 = input.next();if (field.getType().getName().contains("String")) {//获取的字段是String类型field.set(person, s1);} else if (field.getType().getName().contains("Integer")) {//获取的字段是Integer类型field.set(person, Integer.parseInt(s1));} else if (field.getType().getName().contains("Boolean")) {//获取字段是Boolean类型field.set(person, Boolean.parseBoolean(s1));}}}return person;}
}public class text {public static void main(String[] args) throws IllegalAccessException {Person person = new Person();PersonInput personInput = new PersonInput();personInput.process(person);PersonDisplay personDisplay = new PersonDisplay();personDisplay.process(person);}
}3.2 experiment2
2.在第一题目的基础上，编写注解@Column,
// 属性有Label 表示类的属性的显示名称，
// Nullable 表示是否允许属性值为空，
// MaxLength 表示文本属性的最大长度，
// MinLength表示文本属性的最小长度，
// MaxValue表示最大值，
// MinValue表示最小值，
// 把注解@Column加在Person类的每个属性上，在输入Person时根据注解@Column的配置进行校验。
// 第一题的@Label只标注在类上。根据注解生成Person类对应的数据库表创建语句，以及生成数据库表的删除、新增、修改SQL语句。
// 并利用JDBC，实现数据库操作。
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;// 2.在第一题目的基础上，编写注解@Column,
// 属性有Label 表示类的属性的显示名称，
// Nullable 表示是否允许属性值为空，
// MaxLength 表示文本属性的最大长度，
// MinLength表示文本属性的最小长度，
// MaxValue表示最大值，
// MinValue表示最小值，
// 把注解@Column加在Person类的每个属性上，在输入Person时根据注解@Column的配置进行校验。
// 第一题的@Label只标注在类上。根据注解生成Person类对应的数据库表创建语句，以及生成数据库表的删除、新增、修改SQL语句。
// 并利用JDBC，实现数据库操作。
@Target({ElementType.FIELD, ElementType.TYPE})
@Retention(RetentionPolicy.RUNTIME)
public @interface Column {Label label(); // 表示类的属性的显示名称，boolean Nullable() default false;// Nullable 表示是否允许属性值为空int MaxLength() default 100;// MaxLength 表示文本属性的最大长度int MinLength() default 0;// MinLength表示文本属性的最小长度int MaxValue() default 999999999;// MaxValue表示最大值int MinValue() default 0;// MinValue表示最小值}
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;@Target({ElementType.FIELD, ElementType.TYPE})
@Retention(RetentionPolicy.RUNTIME)
public @interface Label {String value();
}package homework4.experiment;import java.lang.reflect.Field;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.util.Scanner;/*** 把注解@Column加在Person类的每个属性上，在输入Person时根据注解@Column的配置进行校验。* 第一题的@Label只标注在类上。根据注解生成Person类对应的数据库表创建语句，以及生成数据库表的删除、新增、修改SQL语句。* 并利用JDBC，实现数据库操作。*/
public class CreateSQL {static PreparedStatement pd = null;static ResultSet rs;static Scanner input = new Scanner(System.in);public String CreateTable(Person person) {Class<? extends Person> clazz = person.getClass();Field[] fields = clazz.getDeclaredFields();Label name = clazz.getAnnotation(Column.class).label();StringBuilder sql = new StringBuilder("create table if not exists " + name.value() + "(\n");for (Field field : fields) {String str = field.getAnnotation(Column.class).label().value();int maxLength = field.getAnnotation(Column.class).MaxLength();//如果时Integer类型if (field.getType().getName().contains("Integer")) {sql.append(str).append(" int,\n");}//如果是Boolean或者String类型if (field.getType().getName().contains("String") || field.getType().getName().contains("Boolean")) {sql.append(str).append(" varchar(").append(maxLength).append("),\n");}//添加主键if (str.equals("身份证号")) {sql = new StringBuilder(sql.substring(0, sql.length() - 2));//截取字符串sql.append(" primary key,\n");}}sql = new StringBuilder(sql.substring(0, sql.length() - 2));sql.append("\n);");System.out.println(sql);return sql.toString();}public String InsertInf(Person person) {Class<? extends Person> clazz = person.getClass();Label name = clazz.getAnnotation(Column.class).label();StringBuilder sql = new StringBuilder("insert into " + name.value() + " values(");Field[] fields = clazz.getDeclaredFields();for (int i = 0; i < fields.length; i++) {Field field = fields[i];String value = field.getAnnotation(Column.class).label().value();System.out.println("请输入" + value + ": ");String str = input.next();//根据注解@Column的配置进行校验if (!isTrue(field, str)) {i--;continue;}//判断性别输入是否输入正确if (value.equals("性别")) {if (!str.equals("男") && !str.equals("女")) {System.out.println("您输入的性别不符合规范请重新输入！");i--;continue;}}//判断是否结婚输入是否正确if (value.equals("是否结婚")) {if (!str.equals("是") && !str.equals("否")) {System.out.println("您输入的结婚情况不符合规范请重新输入！");i--;continue;}}if (!isContainNum(str)) {sql.append("'").append(str).append("'").append(", ");} else {sql.append(str).append(", ");}}sql = new StringBuilder(sql.substring(0, sql.length() - 2));sql.append(");");System.out.println(sql);return sql.toString();}public String deleteInf(Person person) {Class<? extends Person> clazz = person.getClass();Label name = clazz.getAnnotation(Column.class).label();StringBuilder sql = new StringBuilder("delete from " + name.value() + " where ");Field[] fields = clazz.getDeclaredFields();String value = fields[0].getAnnotation(Column.class).label().value();System.out.println("请输入您要删除的" + value + ": ");String str = input.next();if (!isContainNum(str)) {sql.append(value).append(" = ").append("'").append(str).append("'");} elsesql.append(value).append(" = ").append(str).append(";");System.out.println(sql);return sql.toString();}//更新操作public String updateInf(Person person) {Class<? extends Person> clazz = person.getClass();Label tableName = clazz.getAnnotation(Column.class).label();String sql = "update " + tableName.value() + " set ";Field[] fields = clazz.getDeclaredFields();String[] values = new String[fields.length];System.out.println("请输入要修改的姓名:");String str2 = input.nextLine();System.out.println("请选择您要修改的属性:");for (int i = 0; i < values.length; i++) {values[i] = fields[i].getAnnotation(Column.class).label().value();System.out.println((i + 1) + "--" + values[i]);}String choice = input.nextLine();int choiceNum = Integer.parseInt(choice);String str1;while (true) {System.out.println("请输入修改后的值:");str1 = input.nextLine();if (isTrue(fields[choiceNum - 1], str1)) {break;}}switch (choiceNum) {case 1:if (!isContainNum(str1)) {sql += values[0] + " = " + "\"" + str1 + "\"";} else {sql += values[0] + " = " + str1;}break;case 2:if (!isContainNum(str1)) {sql += values[1] + " = " + "\"" + str1 + "\"";} else {sql += values[1] + " = " + str1;}break;case 3:if (!isContainNum(str1)) {sql += values[2] + " = " + "\"" + str1 + "\"";} else {sql += values[2] + " = " + str1;}break;case 4:if (!isContainNum(str1)) {sql += values[3] + " = " + "\"" + str1 + "\"";} else {sql += values[3] + " = " + str1;}break;case 5:if (!isContainNum(str1)) {sql += values[4] + " = " + "\"" + str1 + "\"";} else {sql += values[4] + " = " + str1;}break;default:break;}if (!isContainNum(str2)) {sql += " where " + fields[0].getAnnotation(Column.class).label() + " = " + "\"" + str2 + "\"";} else {sql += " where " + fields[0].getAnnotation(Column.class).label() + " = " + str2;}System.out.println(sql);return sql;}//根据注解@Column的配置进行校验public boolean isTrue(Field f, String str) {String value = f.getAnnotation(Column.class).label().value();boolean nullable = f.getAnnotation(Column.class).Nullable();int maxLength = f.getAnnotation(Column.class).MaxLength();int minLength = f.getAnnotation(Column.class).MinLength();int maxValue = f.getAnnotation(Column.class).MaxValue();int minValue = f.getAnnotation(Column.class).MinValue();if (!nullable && str.isEmpty()) {System.out.println("输入的信息不能为空！请重新输入");return false;}if (maxLength == 0) {int num;try {num = Integer.parseInt(str);} catch (Exception e) {System.out.println("您输入的" + value + "不符合规范！请重新输入");return false;}if (num < minValue || num > maxValue) {System.out.println("您输入的" + value + "不符合规范！请重新输入");return false;}} else {int len = str.length();if (len > maxLength || len < minLength) {System.out.println("您输入的" + value + "不符合规范！请重新输入");return false;}}return true;}public static boolean isContainNum(String str) {for (int i = 0; i < str.length(); i++) {if (str.charAt(i) > '0' && str.charAt(i) < '9') {return true;}}return false;}
}
public class demo {public static void main(String[] args) {Person person = new Person();Class<? extends Person> c = person.getClass();Label l = c.getAnnotation(Column.class).label();System.out.println(l.value());}
}package homework4.experiment;import java.sql.PreparedStatement;
import java.sql.SQLIntegrityConstraintViolationException;
import java.util.Scanner;/*** 把注解@Column加在Person类的每个属性上，在输入Person时根据注解@Column的配置进行校验。* 第一题的@Label只标注在类上。根据注解生成Person类对应的数据库表创建语句，以及生成数据库表的删除、新增、修改SQL语句。* 并利用JDBC，实现数据库操作。*/
public class ExecuteSQL {static PreparedStatement ps = null;static CreateSQL sql = new CreateSQL();static Scanner input = new Scanner(System.in);static Person person = new Person();public static void main(String[] args) throws Exception {mainMenu();closeConnection();}public static void mainMenu() throws Exception {System.out.println("请选择您要进行的操作：");System.out.println("1--自动生成表Person");System.out.println("2--增加数据");System.out.println("3--删除数据");System.out.println("4--修改数据");System.out.println("5--退出程序");Scanner sc = new Scanner(System.in);int choice = sc.nextInt();switch (choice) {case 1:createTable();mainMenu();break;case 2:insert();mainMenu();break;case 3:delete();mainMenu();break;case 4:update();mainMenu();break;case 5:break;default:System.out.println("请输入正确的选项！");mainMenu();break;}}//建表public static void createTable() throws Exception {System.out.println("生成表中......");String create = sql.CreateTable(person);ps = MySqlDAO.preparedStatement(create);ps.executeUpdate();System.out.println("成功生成");}//向表中添加信息public static void insert() throws Exception {try {String insertSQL = sql.InsertInf(person);ps = MySqlDAO.preparedStatement(insertSQL);ps.executeUpdate();} catch (SQLIntegrityConstraintViolationException e) {System.out.println("您输入的身份证号码有重复，请重新输入");insert();}}//删除信息1public static void delete() throws Exception {String deleteSQL = sql.deleteInf(person);ps = MySqlDAO.preparedStatement(deleteSQL);ps.executeUpdate();}//更新信息public static void update() throws Exception {String updateSQL = sql.updateInf(person);ps = MySqlDAO.preparedStatement(updateSQL);ps.executeUpdate();}public static void closeConnection() throws Exception {ps.close();MySqlDAO.getConnection().close();}}
package homework4.experiment;import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;public class MySqlDAO {public static Connection getConnection() throws Exception {String driverName = "com.mysql.cj.jdbc.Driver";String url = "jdbc:mysql://localhost:3306/demo";String userName = "root";String password = "";//自行填写密码Class.forName(driverName);Connection con = DriverManager.getConnection(url, userName, password);return con;}public static PreparedStatement preparedStatement(String sql) throws Exception {return getConnection().prepareStatement(sql);}
}
package homework4.experiment;/*** 1.创建Person类，Person的属性有：* String name 姓名* String sex 性别* Integer age 年龄,* String idNo 身份证号* Boolean isMarried 是否已婚* 请生成相应的getter、setter方法。请编写注解@Label，表示所注解对象的中文名称，√* 请把@Label注解标注在Person类和Person的每个属性上面。√* 请编写PersonInput类，负责提示录入人员的相关属性，提示必须是注解@Label所标注的中文名称。√* 请编写PersonDisplay，负责显示人员信息，显示时的属性名称必须为注解@Label所标注的中文名称√，* PersonInput类与PersonDisplay类实现了共同的接口PersonAction，接口PersonAction有方法process，方法process的签名为：public Person process(Person person);√*/
@Column(label = @Label("Person"))
public class Person {@Column(label = @Label("姓名"))String name; //姓名@Column(label = @Label("性别"))String sex; //性别@Column(label = @Label("年龄"), MaxValue = 120)Integer age; //年龄@Column(label = @Label("身份证号"))String idNo; //身份证号@Column(label = @Label("是否已婚"))Boolean isMarried; //是否已婚public Person() {}public Person(String name, String sex, Integer age, String idNo, boolean isMarried) {this.name = name;this.sex = sex;this.age = age;this.idNo = idNo;this.isMarried = isMarried;}public String getName() {return name;}public void setName(String name) {this.name = name;}public String getSex() {return sex;}public void setSex(String sex) {this.sex = sex;}public Integer getAge() {return age;}public void setAge(Integer age) {this.age = age;}public String getIdNo() {return idNo;}public void setIdNo(String idNo) {this.idNo = idNo;}public Boolean isMarried() {return isMarried;}public void setMarried(Boolean married) {isMarried = married;}
}
四、TCP、UDP
4.1 experiment1
请分别采用TCP、UDP协议编程实现一对一的文件上传。
TCP：
import java.io.*;
import java.net.InetAddress;
import java.net.Socket;public class Client {public static void main(String[] args) throws Exception {//1.创建一个socket连接Socket socket = new Socket(InetAddress.getByName("localhost"), 9000);//2.创建一个输出流OutputStream os = socket.getOutputStream();//3.文件流,读入文件FileInputStream fis = new FileInputStream(new File("E:\\学习\\代码\\AdvancedJAVA\\src\\homework5\\experiment1\\header-logo.png"));//4.写出文件byte[] buffer = new byte[1024];int lens;while ((lens = fis.read(buffer)) != -1) {os.write(buffer, 0, lens);}//通知服务器，我已经传输完了，已经结束了。socket.shutdownOutput();//我已经传输完了// 确定服务器接收完毕，才能够断开连接InputStream is = socket.getInputStream();ByteArrayOutputStream baos = new ByteArrayOutputStream();byte[] buffer2 = new byte[1024];int lens2;while ((lens2 = is.read(buffer2)) != -1) {baos.write(buffer2, 0, lens2);}System.out.println(baos.toString());//5.关闭资源baos.close();fis.close();os.close();socket.close();}
}
import java.io.*;
import java.net.ServerSocket;
import java.net.Socket;
import java.nio.charset.StandardCharsets;public class Server {public static void main(String[] args) throws IOException {//1创建服务ServerSocket serverSocket = new ServerSocket(9000);//2监听客户端的连接Socket socket = serverSocket.accept();//阻塞式监听，会一直等待客户端。//3获取输入流InputStream is = socket.getInputStream();//4文件输出,管道输出流FileOutputStream fos = new FileOutputStream(new File("receive.png"));byte[] buffer = new byte[1024];int lens;while ((lens = is.read(buffer)) != -1) {fos.write(buffer, 0, lens);}//通知客户端我接受完毕了OutputStream os = socket.getOutputStream();os.write("我接收完毕了，你可以断开了".getBytes(StandardCharsets.UTF_8));//关闭资源os.close();fos.close();is.close();socket.close();serverSocket.close();}
}
UDP：
import java.io.FileOutputStream;
import java.net.DatagramPacket;
import java.net.DatagramSocket;public class receive {public static void main(String[] args) throws Exception {//开放端口DatagramSocket socket = new DatagramSocket(9090);//接收数据（包）byte[] buffer = new byte[1024];DatagramPacket packet = new DatagramPacket(buffer, 0, buffer.length);//接收socket.receive(packet);//将得到的packet进行拆包int len = packet.getLength();byte[] data = packet.getData();String str = new String(data, 0, len);//利用FileOutputStream将数据写入到文件中String targetPath = "E:\\学习\\代码\\AdvancedJAVA\\src\\homework5\\experiment1\\21.png";FileOutputStream fos = new FileOutputStream(targetPath);fos.write(str.getBytes());//关闭相关流System.out.println("文件上传完毕");fos.close();socket.close();//关闭连接socket.close();}
}
import java.io.FileInputStream;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetAddress;//不需要连接服务器
public class send {public static void main(String[] args) throws Exception {//1.建立一个socketDatagramSocket socket = new DatagramSocket();//2.建立一个包//发送给谁InetAddress localhost = InetAddress.getByName("localhost");int port = 9090;FileInputStream fis = new FileInputStream("E:\\学习\\代码\\AdvancedJAVA\\src\\homework5\\experiment1\\2.png");byte[] buffer = new byte[1024];int lens;String str = "";while ((lens = fis.read(buffer)) != -1) {str += new String(buffer, 0, lens);}buffer = str.getBytes();DatagramPacket packet = new DatagramPacket(buffer, buffer.length, localhost, port);//3.发送包socket.send(packet);//关闭流socket.close();}
}
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetAddress;//不需要连接服务器
public class UDPClient {public static void main(String[] args) throws Exception {//建立一个SocketDatagramSocket socket = new DatagramSocket();//建个包String msg = "你好啊，服务器!";//发送给谁InetAddress address = InetAddress.getByName("localhost");int port = 9090;//数据，数据的起始长度，要发送给谁DatagramPacket packet = new DatagramPacket(msg.getBytes(), 0, msg.getBytes().length, address, port);//发送包socket.send(packet);//关闭socket.close();}
}
import java.net.DatagramPacket;
import java.net.DatagramSocket;public class UDPReceive {public static void main(String[] args) throws Exception {//开放端口DatagramSocket socket = new DatagramSocket(9090);//接收数据（包）byte[] buffer = new byte[1024];DatagramPacket packet = new DatagramPacket(buffer, 0, buffer.length);//接收socket.receive(packet);System.out.println(packet.getAddress().getHostAddress());System.out.println(new String(packet.getData(), 0, packet.getLength()));socket.close();}
}
4.2 experiment2
2.编写一对多的聊天程序，程序由服务器和客户端两部分构成，两部分的交互方式如下：
a.客户端发送命令：<register name=”xu”/> 给服务器端注册用户，服务器端如果允许注册，则返回消息：<result command=”register” state=”ok” />，否则返回消息：<result command=”register” state=”error” message=”” />
b.客户端发送命令：<login name=”xu”/> 给服务器端进行登录, 服务器端如果允许登录，则返回消息：<result command=” login ” state=”ok” />，否则返回消息：<result command=”login” state=”error” message=”” />；
c.客户端发送命令：<message from=”xu” to=”zhang” message=”this is a test”> 给服务器端，服务器端收到命令后返回消息：<result command=” message ” state=”ok” />；
d.服务器向指定客户端发送命令：<message from=”xu” to=”zhang” message=”this is a test”>，如果客户端收到消息，则返回：<result command=” message ” state=”ok” />，如果message命令中的 from属性为空，则表示由服务器发送的消息。
e.客户端发送命令：<logout name=”xu”/> 给服务器端进行注销登录, 服务器端如果允许注销登录，则返回消息：<result command=” logout ” state=”ok” />，否则返回消息：<result command=”loginout” state=”error” message=”” />；
程序可以采用GUI，也可采用命令行的方式。
package homework5.experiment2;import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.InetAddress;
import java.net.Socket;
import java.util.Scanner;public class Client01 {private static String user;public static void main(String[] args) throws IOException {System.out.println("————————欢迎来到魏乐天设计的聊天界面窗口————————");Socket socket = new Socket(InetAddress.getByName("localhost"), 8888);Scanner scanner = new Scanner(System.in);while (true) {InputStreamReader reader = new InputStreamReader(socket.getInputStream());BufferedReader bufferedReader = new BufferedReader(reader);PrintWriter writer = new PrintWriter(socket.getOutputStream());System.out.println("输入相应数字选择您要进行的操作");System.out.println("1--注册用户");System.out.println("2--登陆账户");System.out.println("3--发送信息");System.out.println("4--登出账户");System.out.println("5--接收信息");System.out.println("其他数字--退出系统");int choice = scanner.nextInt();String instruction = "";if (choice == 1) {System.out.print("请输入您想要注册的账户名称:");String name = scanner.next();instruction = "<register name=\"" + name + "\"/> ";writer.println(instruction);writer.flush();} else if (choice == 2) {System.out.print("请输入您想要登录的账户名称:");user = scanner.next();instruction = "<login name=\"" + user + "\"/>";writer.println(instruction);writer.flush();} else if (choice == 3) {System.out.print("请输入您想要发送的用户名称:");String toUser = scanner.next();System.out.println(toUser);System.out.println("你说:");String message = scanner.next();System.out.println(message);instruction = "<message from=\"" + user + "\" to=\"" + toUser + "\" message=\"" + message + "\">";writer.println(instruction);writer.flush();} else if (choice == 4) {System.out.print("请输入您想要登出的账户:");String name = scanner.next();instruction = "<logout name=\"" + name + "\"/>";writer.println(instruction);writer.flush();} else if (choice == 5) {System.out.println("等待接受消息中...");String response0 = bufferedReader.readLine();String[] strings = response0.split("\"");String fromUser = strings[7];String message = strings[5];System.out.println(fromUser + "说:" + message);continue;} else {instruction = "<quit>";writer.println(instruction);writer.flush();break;}String response = bufferedReader.readLine();String[] strings = response.split("\"");String command = strings[1];String state = strings[3];if (command.equals("register")) {if (state.equals("ok")) {System.out.println("注册成功！");} else {System.out.println("已存在该用户，注册失败请重新注册");}} else if (command.equals("login")) {if (state.equals("ok")) {System.out.println("登陆成功！");} else {System.out.println("该用户不存在(或重复登陆)，请重新登录");}} else if (command.equals("logout")) {if (state.equals("ok")) {System.out.println("成功退出账户！");} else {System.out.println("该账户不存在(未登录)，请重试");}} else if (command.equals("message")) {if (state.equals("ok")) {System.out.println("成功发送消息！");} else {System.out.println("您对话的用户不存在(未登录),请重试");}}}socket.close();System.out.println("---成功退出系统---");}
}package homework5.experiment2;import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.InetAddress;
import java.net.Socket;
import java.util.Scanner;public class Client02 {private static String user;public static void main(String[] args) throws IOException {System.out.println("————————欢迎来到魏乐天设计的聊天界面窗口————————");Socket socket = new Socket(InetAddress.getByName("localhost"), 8888);Scanner scanner = new Scanner(System.in);while (true) {InputStreamReader reader = new InputStreamReader(socket.getInputStream());PrintWriter writer = new PrintWriter(socket.getOutputStream());BufferedReader bufferedReader = new BufferedReader(reader);System.out.println("请选择您要进行的操作");System.out.println("1--注册用户");System.out.println("2--登陆账户");System.out.println("3--发送信息");System.out.println("4--登出账户");System.out.println("5--接收信息");System.out.println("其他数字--退出系统");int choice = scanner.nextInt();String instruction = "";if (choice == 1) {System.out.print("请输入您想要注册的账户名称:");String name = scanner.next();instruction = "<register name=\"" + name + "\"/> ";writer.println(instruction);writer.flush();} else if (choice == 2) {System.out.print("请输入您想要登录的账户名称:");user = scanner.next();instruction = "<login name=\"" + user + "\"/>";writer.println(instruction);writer.flush();} else if (choice == 3) {System.out.print("请输入您想要发送的用户名称:");String toUser = scanner.next();System.out.println(toUser);System.out.println("你说:");String message = scanner.next();System.out.println(message);instruction = "<message from=\"" + user + "\" to=\"" + toUser + "\" message=\"" + message + "\">";System.out.println(instruction);writer.println(instruction);writer.flush();} else if (choice == 4) {System.out.print("请输入您想要登出的账户:");String name = scanner.next();instruction = "<logout name=\"" + name + "\"/>";writer.println(instruction);writer.flush();} else if (choice == 5) {System.out.println("等待接受消息中...");String response0 = bufferedReader.readLine();String[] strings = response0.split("\"");String fromUser = strings[7];String message = strings[5];System.out.println(fromUser + "说:" + message);continue;} else {instruction = "<quit>";writer.println(instruction);writer.flush();break;}String response = bufferedReader.readLine();String[] strings = response.split("\"");String command = strings[1];String state = strings[3];if (command.equals("register")) {if (state.equals("ok")) {System.out.println("注册成功！");} else {System.out.println("已存在该用户，注册失败请重新注册");}} else if (command.equals("login")) {if (state.equals("ok")) {System.out.println("登陆成功！");} else {System.out.println("该用户不存在(或重复登陆)，请重新登录");}} else if (command.equals("logout")) {if (state.equals("ok")) {System.out.println("成功退出账户！");} else {System.out.println("该账户不存在(未登录)，请重试");}} else if (command.equals("message")) {if (state.equals("ok")) {System.out.println("成功发送消息！");} else {System.out.println("您对话的用户不存在(未登录),请重试");}}}socket.close();System.out.println("---成功退出系统---");}
}package homework5.experiment2;import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.InetAddress;
import java.net.Socket;
import java.util.Scanner;public class Client03 {private static String user;public static void main(String[] args) throws IOException {System.out.println("————————欢迎来到魏乐天设计的聊天界面窗口————————");Socket socket = new Socket(InetAddress.getByName("localhost"), 8888);Scanner scanner = new Scanner(System.in);while (true) {InputStreamReader reader = new InputStreamReader(socket.getInputStream());BufferedReader bufferedReader = new BufferedReader(reader);PrintWriter writer = new PrintWriter(socket.getOutputStream());System.out.println("请选择您要进行的操作");System.out.println("1--注册用户");System.out.println("2--登陆账户");System.out.println("3--发送信息");System.out.println("4--登出账户");System.out.println("5--接收信息");System.out.println("其他数字--退出系统");int choice = scanner.nextInt();String instruction = "";if (choice == 1) {System.out.print("请输入您想要注册的账户名称:");String name = scanner.next();instruction = "<register name=\"" + name + "\"/> ";writer.println(instruction);writer.flush();} else if (choice == 2) {System.out.print("请输入您想要登录的账户名称:");user = scanner.next();instruction = "<login name=\"" + user + "\"/>";writer.println(instruction);writer.flush();} else if (choice == 3) {System.out.print("请输入您想要发送的用户名称:");String toUser = scanner.next();System.out.println(toUser);System.out.println("你说:");String message = scanner.next();System.out.println(message);instruction = "<message from=\"" + user + "\" to=\"" + toUser + "\" message=\"" + message + "\">";writer.println(instruction);writer.flush();} else if (choice == 4) {System.out.print("请输入您想要登出的账户:");String name = scanner.next();instruction = "<logout name=\"" + name + "\"/>";writer.println(instruction);writer.flush();} else if (choice == 5) {System.out.println("等待接受消息中...");String response0 = bufferedReader.readLine(); //当没有客户端发送消息时会在这里阻塞，直到收到消息String[] strings = response0.split("\"");String fromUser = strings[7];String message = strings[5];System.out.println(fromUser + "说:" + message);continue;} else {instruction = "<quit>";writer.println(instruction);writer.flush();break;}String response = bufferedReader.readLine();String[] strings = response.split("\"");String command = strings[1];String state = strings[3];if (command.equals("register")) {if (state.equals("ok")) {System.out.println("注册成功！");} else {System.out.println("已存在该用户，注册失败请重新注册");}} else if (command.equals("login")) {if (state.equals("ok")) {System.out.println("登陆成功！");} else {System.out.println("该用户不存在(或重复登陆)，请重新登录");}} else if (command.equals("logout")) {if (state.equals("ok")) {System.out.println("成功退出账户！");} else {System.out.println("该账户不存在(未登录)，请重试");}} else if (command.equals("message")) {if (state.equals("ok")) {System.out.println("成功发送消息！");} else {System.out.println("您对话的用户不存在(未登录),请重试");}}}socket.close();System.out.println("---成功退出系统---");}
}package homework5.experiment2;import java.io.IOException;
import java.io.PrintWriter;
import java.net.ServerSocket;
import java.net.Socket;
import java.util.Hashtable;public class Server {//利用图存储用户的登录状态static Hashtable<String, Boolean> user = new Hashtable<>();//利用图存储用户登录的客户端static Hashtable<String, PrintWriter> client = new Hashtable<>();public static void main(String[] args) throws IOException {//服务器在本机8888端口进行监听，等待连接ServerSocket serverSocket = new ServerSocket(8888);System.out.println("服务器在本机8888端口进行监听，等待连接...");while (true) {Socket socket = serverSocket.accept();System.out.println("成功监听到客户端" + socket.getPort());SocketHandler handler = new SocketHandler(socket);Thread thread = new Thread(handler);thread.start();}}
}
package homework5.experiment2;import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.Socket;public class SocketHandler implements Runnable {private Socket socket;public SocketHandler(Socket socket) {this.socket = socket;}@Overridepublic void run() {try {InputStreamReader reader = new InputStreamReader(socket.getInputStream());BufferedReader bufferedReader = new BufferedReader(reader);PrintWriter writer = new PrintWriter(socket.getOutputStream());PrintWriter toWriter = null;while (true) {String request = bufferedReader.readLine();if (request == null) {continue;}String line = "";String[] strings = request.split("\"");String name = strings[1];if (request.startsWith("<register")) {if (!Server.user.containsKey(name)) {Server.user.put(name, false);line = "<result command=\"register\" state=\"ok\" />";} else {line = "<result command=\"register\" state=\"error\" message=\"\" />";}writer.println(line);writer.flush();} else if (request.startsWith("<login")) {if (Server.user.containsKey(name) && !Server.user.get(name)) {line = "<result command=\"login\" state=\"ok\" />";Server.user.put(name, true);Server.client.put(name, writer);} else {line = "<result command=\"login\" state=\"error\" message=\"\"/>";}writer.println(line);writer.flush();} else if (request.startsWith("<message")) {String toUser = strings[3];String message = strings[5];if (Server.user.containsKey(toUser) && Server.user.get(toUser)) {toWriter = Server.client.get(toUser);System.out.println(toUser);System.out.println(toWriter);line = "<result command= \"message\" state=\"ok\" message = \"" + message + "\" form = \"" + name + "\"/>";toWriter.println(line);toWriter.flush();} else {line = "<result command= \"message\" state=\"error\" message=\"\" />";}writer.println(line);writer.flush();} else if (request.startsWith("<logout")) {if (Server.user.containsKey(name) && Server.user.get(name)) {Server.user.put(name, true);line = "<result command= \"logout\" state=\"ok\" />";} else {line = "<result command=\"logout\" state=\"error\" message=\"\" />";}writer.println(line);writer.flush();break;}}//关闭相关流writer.close();toWriter.close();bufferedReader.close();socket.close();} catch (IOException e) {e.printStackTrace();}}
}
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