使用Maven工具实现学生管理系统
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2022-05-06 20:30:32
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Main.java
package com.zzu.client;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.Scanner;
import java.util.UUID;
import com.zzu.tool.db.DBLink;
import com.zzu.tool.db.IRowMapper;
public class Main {
public static void main(String[] args) {
System.out.println("*********************************");
System.out.println("*\t\t\t\t*");
System.out.println("*\t欢迎使用学生信息管理系统\t*");
System.out.println("*\t\t\t\t*");
System.out.println("*********************************");
while (true) {
menu();
}
}
static void menu() {
System.out.println("1、添加学生信息");
System.out.println("2、删除学生信息");//学号
System.out.println("3、修改学生信息");//地址传递
System.out.println("4、查询学生信息");//name
System.out.println("请输入操作，以Enter键结束:");
Scanner scanner = new Scanner(System.in);
int option = scanner.nextInt();
switch (option) {
case 1:{
System.out.println("请输入学生姓名");
String name = scanner.next();
System.out.println("请输入学生手机号");
String mobile = scanner.next();
System.out.println("请输入学生地址");
String address = scanner.next();
System.out.println("请输入学生学号");
String id = scanner.next();
String sql ="select id from user_inforrr where id=?";
if(new DBLink().exist(sql ,id)) {
System.out.println("该学号已存在，操作终止！");
return;
}
sql="insert into user_inforrr (name,mobile,address,id) values(?,?,?,?)";
if(new DBLink().update(sql,name,mobile,address,id)) {
System.out.println("添加成功！");
return;
}
System.out.println("添加失败！");
break;
}
case 2:{
System.out.println("请输入学生学号");
String id = scanner.next();
String sql ="select id from user_inforrr where id=?";
if(!new DBLink().exist(sql ,id)) {
System.out.println("该学号不存在，操作终止！");
return;
}
sql ="delete from user_inforrr where id=?";
if(new DBLink().update(sql,id)) {
System.out.println("删除成功！");
return;
}
System.out.println("删除失败！");
break;
}
case 3:{
System.out.println("请输入学生学号");
String id = scanner.next();
String sql ="select id from user_inforrr where id=?";
if(!new DBLink().exist(sql ,id)) {
System.out.println("该学号不存在，操作终止！");
return;
}
System.out.println("请输入新学生姓名");
String name = scanner.next();
System.out.println("请输入新学生手机号");
String mobile = scanner.next();
System.out.println("请输入新学生地址");
String address = scanner.next();
sql = "update user_inforrr set name=?, mobile=?, address=? where id=?";
if(new DBLink().update(sql,name,mobile,address,id)) {
System.out.println("修改成功！");
return;
}
System.out.println("修改失败！");
break;
}
case 4:{
System.out.println("请输入学生学号");
String id = scanner.next();
String sql ="select id,name,mobile,address from user_inforrr where id=?";
class RowMapper implements IRowMapper{
public void rowMapper(ResultSet rs) {
try {
if(rs.next()) {
String id = rs.getString("id");
String name = rs.getString("name");
String mobile = rs.getString("mobile");
String address = rs.getString("address");
System.out.println(id+","+name+","+mobile+","+address);
return;
}
System.out.println("没有找到学生信息");
} catch (SQLException e) {
e.printStackTrace();
}
}
}
IRowMapper rowMapper = new RowMapper();
new DBLink().select(sql, rowMapper,id);
break;
}
default:
System.out.println("I'm Sorry,there is not the "+option+" option,please try again.");
}
}
}DBLink.java
package com.zzu.tool.db;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import org.apache.log4j.Logger;
import com.zzu.tool.PropertiesTool;
/**
* 数据库管理工具类
*
* @author ZhangYutong
*/
public class DBLink {
private Logger logger = Logger.getLogger(DBLink.class);
/**
* 获取数据库连接
*
* @author ZhangYutong
*/
private Connection getConnection() {
try {
Class.forName("com.mysql.jdbc.Driver");//加载驱动
String userName = PropertiesTool.getValue("db.username");
String password = PropertiesTool.getValue("db.password");
String url = PropertiesTool.getValue("db.url");
return DriverManager.getConnection(url, userName, password);//获取连接
} catch (Exception e) {
logger.debug(e.getMessage(), e);
}
return null;
}
/**
* 判断SQL语句是否能查出数据
*
* @author ZhangYutong
*/
public boolean exist(String sql) {
Connection connection = null;
Statement statement =null;
ResultSet resultSet=null;
try {
connection = getConnection();//获取连接
statement = connection.createStatement();
resultSet= statement.executeQuery(sql);//执行sql,将查询的数据存到ResultSet类型的变量中
return resultSet.next();
} catch (Exception e) {
logger.debug(e.getMessage(), e);
}finally {
close(resultSet,statement,connection);
}
return false;
}
/**
* 判断SQL语句是否能查出数据
*
* @author ZhangYutong
*/
public boolean exist(String sql, Object ...params) {
Connection connection = null;
PreparedStatement preparedStatement =null;
ResultSet resultSet=null;
try {
connection = getConnection();//获取连接
preparedStatement = connection.prepareStatement(sql);
for (int i = 0; i < params.length; i++) {
preparedStatement.setObject(i+1, params[i]);
}
resultSet= preparedStatement.executeQuery();//执行sql,将查询的数据存到ResultSet类型的变量中
return resultSet.next();
} catch (Exception e) {
logger.debug(e.getMessage(), e);
}finally {
close(resultSet,preparedStatement,connection);
}
return false;
}
/**
* 查询数据
*
* @author ZhangYutong
*/
public void select(String sql,IRowMapper rowMapper) {//接口无法创建对象，所以rowMapper参数一定指向IRowMapper接口实现类对象
Connection connection = null;
Statement statement =null;
ResultSet resultSet=null;
try {
connection = getConnection();//获取连接
statement = connection.createStatement();
resultSet= statement.executeQuery(sql);//执行sql,将查询的数据存到ResultSet类型的变量中
rowMapper.rowMapper(resultSet);//因为rowMapper参数指向IRowMapper接口实现类对象，所以此处将调用接口实现类中所实现的rowMapper方法 多态
} catch (Exception e) {
logger.debug(e.getMessage(), e);
}finally {//释放资源
close(resultSet,statement,connection);
}
}
/**
* 查询数据
*
* @author ZhangYutong
*/
public void select(String sql,IRowMapper rowMapper,Object ...params) {
Connection connection = null;
PreparedStatement preparedStatement =null;
ResultSet resultSet=null;
try {
connection = getConnection();//获取连接
preparedStatement= connection.prepareStatement(sql);//含有？号占位符的sql
for (int i = 0; i < params.length; i++) {
preparedStatement.setObject(i+1, params[i]);//为？号赋值
}
resultSet= preparedStatement.executeQuery();//执行sql
rowMapper.rowMapper(resultSet);//因为rowMapper参数指向IRowMapper接口实现类对象，所以此处将调用接口实现类中所实现的rowMapper方法 多态
} catch (Exception e) {
logger.debug(e.getMessage(), e);
}finally {//释放资源
close(resultSet,preparedStatement,connection);
}
}
/**
* 修改（insert、update和delete）数据
*
* @author ZhangYutong
*/
public boolean update(String sql) {
Connection connection = null;
Statement statement = null;
try {
connection = getConnection();//获取数据库连接对象，一个对象表示一次数据库连接
statement = connection.createStatement();//获取Statement对象
int result = statement.executeUpdate(sql);//执行sql语句，返回受影响的行数，仅限于数据insert、update和delete
return result>0;//处理结果
} catch (Exception e) {
logger.debug(e.getMessage(), e);
}finally {//即便有异常也会执行代码
close(statement,connection);
}
return false;
}
/**
* 修改（insert、update和delete）数据
*
* @author ZhangYutong
*/
public boolean update(String sql,Object ...params) {
Connection connection= null;
PreparedStatement preparedStatement= null;
try {
connection= getConnection();
preparedStatement= connection.prepareStatement(sql);//含有？号占位符的sql
for (int i = 0; i < params.length; i++) {
preparedStatement.setObject(i+1, params[i]);//为？号赋值
}
return preparedStatement.executeUpdate()>0;
} catch (Exception e) {
logger.debug(e.getMessage(), e);
}finally {
close(preparedStatement,connection);
}
return false;
}
/**
* 释放资源
*
* @author ZhangYutong
*/
private void close(Statement statement,Connection connection) {
try {
if(statement!=null) {//有可能由于异常导致statement没有赋值，比如url出错
statement.close();
}
} catch (SQLException e) {
logger.debug(e.getMessage(), e);
}
try {
if(connection!=null) {
connection.close();
}
} catch (SQLException e) {
logger.debug(e.getMessage(), e);
}
}
/**
* 释放资源
*
* @author ZhangYutong
*/
private void close(ResultSet resultSet,Statement statement,Connection connection) {//重载
try {
if(resultSet!=null) {
resultSet.close();
}
} catch (SQLException e) {
logger.debug(e.getMessage(), e);
}
close(statement,connection);
}
}
IRowMapper.java
package com.zzu.tool.db;
import java.sql.ResultSet;
public interface IRowMapper {
void rowMapper(ResultSet rs);
}
PropertiesTool.java
package com.zzu.tool;
import java.io.IOException;
import java.io.InputStream;
import java.util.Properties;
public class PropertiesTool {
private static Properties properties = new Properties();
static {
InputStream inputStream = PropertiesTool.class.getClassLoader().getResourceAsStream("db.properties");//将db.properties变为javaIO流对象
try {
properties.load(inputStream);
} catch (IOException e) {
e.printStackTrace();
}
}
public static String getValue(String key) {
return properties.getProperty(key);
}
}
db.properties
db.username=root
db.password=root
db.url=jdbc:mysql://localhost:3306/testlog4j.properties
# DEBUG\u8BBE\u7F6E\u8F93\u51FA\u65E5\u5FD7\u7EA7\u522B\uFF0C\u7531\u4E8E\u4E3ADEBUG\uFF0C\u6240\u4EE5ERROR\u3001WARN\u548CINFO \u7EA7\u522B\u65E5\u5FD7\u4FE1\u606F\u4E5F\u4F1A\u663E\u793A\u51FA\u6765
log4j.rootLogger=DEBUG,Console,RollingFile
#\u5C06\u65E5\u5FD7\u4FE1\u606F\u8F93\u51FA\u5230\u63A7\u5236\u53F0
log4j.appender.Console=org.apache.log4j.ConsoleAppender
log4j.appender.Console.layout=org.apache.log4j.PatternLayout
log4j.appender.Console.layout.ConversionPattern= [%-5p]-[%d{yyyy-MM-dd HH:mm:ss}] -%l -%m%n
#\u5C06\u65E5\u5FD7\u4FE1\u606F\u8F93\u51FA\u5230\u64CD\u4F5C\u7CFB\u7EDFD\u76D8\u6839\u76EE\u5F55\u4E0B\u7684log.log\u6587\u4EF6\u4E2D
log4j.appender.RollingFile=org.apache.log4j.DailyRollingFileAppender
log4j.appender.RollingFile.File=D://log.log
log4j.appender.RollingFile.layout=org.apache.log4j.PatternLayout
log4j.appender.RollingFile.layout.ConversionPattern=%d [%t] %-5p %-40.40c %X{traceId}-%m%n
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