maven实现学生管理系统
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2022-05-06 16:08:36
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项目结构
pom.xml
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.jd</groupId>
<artifactId>xueshengguanlixitong</artifactId>
<packaging>war</packaging>
<version>0.0.1-SNAPSHOT</version>
<name>xueshengguanli Maven Webapp</name>
<url>http://maven.apache.org</url>
<dependencies>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>3.8.1</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>javax.servlet</groupId>
<artifactId>javax.servlet-api</artifactId>
<version>3.1.0</version>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>log4j</groupId>
<artifactId>log4j</artifactId>
<version>1.2.17</version>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>6.0.6</version>
</dependency>
</dependencies>
<build>
<finalName>xueshengguanlixitong</finalName>
</build>
<profiles>//以下代码是为了实现lambda表达式的简化
<profile>
<id>jdk1.8</id>
<activation>
<activeByDefault>true</activeByDefault>
<jdk>1.8</jdk>
</activation>
<properties>
<maven.compiler.source>1.8</maven.compiler.source>
<maven.compiler.target>1.8</maven.compiler.target>
<maven.compiler.compilerVersion>1.8</maven.compiler.compilerVersion>
</properties>
</profile>
</profiles>
</project>
工具：
log4j.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
db.properties：存放连接数据库时的用到的数据，这样修改连接的设备时不需从java文件中修改
db.user_name = root;
db.password = root;
db.url =jdbc:mysql://127.0.0.1:3306/test1;
PropertiesTool：架起DBLink和db.properties之间的桥梁
package com.jd.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);//将inputStream通过 load方法把key
} catch (IOException e) {
e.printStackTrace();
}
}
public static void main(String [] ages) {
String userName = properties.getProperty("db.username");
System.out.print(userName);
}
public static String getValue(String key) {
return properties.getProperty(key);
}
}
IRowMapper：函数式接口
package com.jd.tool.db.aa;
import java.sql.ResultSet;
public interface IRowMapper {
void rowMapper(ResultSet rs);
}
DBLink：jdbc用到的方法
package com.jd.tool.db.aa;
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.jd.tool.PropertiesTool;
/**
* sql管理工具类
*
* @author SONG
*/
public class DBLink {
private static Logger logger = Logger.getLogger(DBLink.class);
/*try {
Class.forName("com.mysql.jdbc.Driver");
String url = "jdbc:mysql://127.0.0.1:3306/test1";
connection=DriverManager.getConnection(url, "root", "root");
statement = connection.createStatement();
long result = statement.executeLargeUpdate(sql);
statement.close();//如果上面代码出现异常，则该行代码及其下面代码无法执行，所以资源无法释放；比如sql语句语法错误，则statement和connection无法释放
connection.close();*/
/**
* 获取数据库连接
*
*@author SONG
*/
private static Connection getConnection() {
try {
Class.forName("com.mysql.jdbc.Driver");
String userName = PropertiesTool.getValue("db.username");
String password =PropertiesTool.getValue("db.password");
String url = PropertiesTool.getValue("db.url");
return DriverManager.getConnection(url, userName,password);
} catch (Exception e) {
// TODO Auto-generated catch block
logger.debug(e.getMessage(),e);
}
return null;
}
/**
* 查询数据
*
*@author SONG
*/
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
//此处的rowMapper就是一个形参，到时候接口实现类里的实参再传给它
Connection connection =null;
Statement statement =null;
ResultSet resultSet =null;
try {
connection = getConnection();
statement = connection.createStatement();
resultSet = statement.executeQuery(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 {
close(resultSet,statement,connection);
}
}
/**
* 查询数据
*
*@author SONG
*/
public void select(String sql,IRowMapper rowMapper, Object ...pramas ) {//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
//此处的rowMapper就是一个形参，到时候接口实现类里的实参再传给它
Connection connection =null;
Statement statement =null;
ResultSet resultSet =null;
PreparedStatement preparedStatement =null;
try {
connection = getConnection();
preparedStatement = connection.prepareStatement(sql);//含有？占位符的sql
for (int i = 0; i < pramas.length; i++) {
preparedStatement.setObject(i+1, pramas[i]);//为？赋值
}
resultSet = preparedStatement.executeQuery();
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 {
close(resultSet,preparedStatement,connection);
}
}
/**
* 判断sql语句能否查出数据
*
*@author SONG
*/
public boolean exist(String sql) {//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
//此处的rowMapper就是一个形参，到时候接口实现类里的实参再传给它
Connection connection =null;
Statement statement =null;
ResultSet resultSet =null;
try {
connection = getConnection();
statement = connection.createStatement();
resultSet = statement.executeQuery(sql);
return resultSet.next();
} catch (Exception e) {
logger.debug(e.getMessage(),e);
}finally {
try {
if(resultSet!=null){
resultSet.close();
}
} catch (SQLException e) {
e.printStackTrace();
}
close(resultSet,statement,connection);
}
return false;
}
/**
* 判断sql语句能否查出数据
*
*@author SONG
*/
public boolean exist(String sql,Object ...pramas) {//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
//此处的rowMapper就是一个形参，到时候接口实现类里的实参再传给它
Connection connection =null;
PreparedStatement preparedStatement =null;
ResultSet resultSet =null;
try {
connection = getConnection();
preparedStatement = connection.prepareStatement(sql);//含有？占位符的sql
for (int i = 0; i < pramas.length; i++) {
preparedStatement.setObject(i+1, pramas[i]);//为？赋值
}
resultSet = preparedStatement.executeQuery();
return resultSet.next();
} catch (Exception e) {
logger.debug(e.getMessage(),e);
}finally {
close(resultSet,preparedStatement,connection);
}
return false;
}
/**
* 修改（insert delete update）数据
*
*@author SONG
*/
public boolean update(String sql) {
Connection connection=null;
Statement statement=null;
try {
connection=getConnection();
statement = connection.createStatement();
long result = statement.executeLargeUpdate(sql);
return result>0;
} catch (Exception e) {
logger.debug(e.getMessage(),e);
}finally {
close(statement,connection);
}
return false;
}
/**
* 修改（insert delete update）数据
*
*@author SONG
*/
public static boolean update(String sql,Object ...pramas) {
Connection connection=null;
PreparedStatement preparedStatement=null;
try {
connection = getConnection();
preparedStatement=connection.prepareStatement(sql);//含有？占位符的sql
for (int i = 0; i < pramas.length; i++) {
preparedStatement.setObject(i+1, pramas[i]);//为？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 SONG
*/
private static void close(Statement statement,Connection connection) {
try {
if(statement!=null) {
statement.close();
}
} catch (SQLException e) {
e.printStackTrace();
}
try {
if(connection!=null) {
connection.close();
}
} catch (SQLException e) {
logger.debug(e.getMessage(),e);
}
}
/**
* 释放资源
*
*@author SONG
*/
private static void close(ResultSet resultSet,Statement statement,Connection connection) {
try {
if(resultSet!=null){
resultSet.close();
}
} catch (SQLException e) {
logger.debug(e.getMessage(),e);
}
close(statement,connection);
}
}
Main：实现功能
package com.jd.client;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.Scanner;
import javax.swing.tree.RowMapper;
import com.jd.tool.db.DBLink;
import com.jd.tool.db.IRowMapper;
public class Main {
private static IRowMapper rowMapper;
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("请输入学号");
String id = scanner.next();
String sql = "select id from user_info where id = ?";
if (new DBLink().exist(sql,id)) {
System.out.println("已经有该学号，重新输入");
return;
}
System.out.println("请输入姓名");
String name = scanner.next();
System.out.println("请输入电话");
String mobile = scanner.next();
System.out.println("请输入地址");
String address = scanner.next();
sql = "insert into user_info(id,name,mobile,address) value(?,?,?,?)";
if (new DBLink().update(sql, id,name,mobile,address)) {
System.out.println("添加成功");
return;
}
System.out.println("添加失败");
break;
}
case 2:{
System.out.println("请输入学号");
String id = scanner.next();
/*String sql = "select id from user_info where id = ?";
if (!new DBLink().exist(sql,id)) {
System.out.println("没有该学号，重新输入");
return;
}*///这里如果有该学号，下面一定删除成功，反之一定失败，所以，这个判断可以不要，直接删了
String sql = "delete from user_info 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("请输入学号");
String id = scanner.next();
String sql = "select id from user_info where id = ?";
if (!new DBLink().exist(sql,id)) {
System.out.println("没有该学号，重新输入");
return;
}
System.out.println("请输入新姓名");
String name = scanner.next();
System.out.println("请输入新电话");
String mobile = scanner.next();
System.out.println("请输入新地址");
String address = scanner.next();
sql="update user_info set name =?,mobile = ?,address = ? where id = ?";
if (new DBLink().update(sql, name,mobile,address,id)) {
System.out.println("更改成功");
return;
}
System.out.println("更改失败");
break;
}
case 4:{
System.out.println("请输入学号");
final String id = scanner.next();
String sql = "select id from user_info where id = ?";
if (!new DBLink().exist(sql,id)) {
System.out.println("没有该学号，重新输入");
return;
}
sql = "select id,name,mobile,address from user_info where id = ?";
//lambda表达式简化
/*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);
}
System.out.println("查询失败");
} catch (SQLException e) {
e.printStackTrace();
}
}
};
IRowMapper rowMapper = new RowMapper();
new DBLink().select(sql,rowMapper,id);*/
//lambda表达式进一步简化
/*IRowMapper rowMapper =(rs)->{
try {
if (rs.next()) {
String name = rs.getString("name");
String mobile = rs.getString("mobile");
String address = rs.getString("address");
System.out.println(id+","+name+","+mobile+","+address);
}
System.out.println("查询失败");
} catch (SQLException e) {
e.printStackTrace();
}
};
new DBLink().select(sql,rowMapper,id);*/
new DBLink().select(sql,(rs)->{
try {
if (rs.next()) {
String name = rs.getString("name");
String mobile = rs.getString("mobile");
String address = rs.getString("address");
System.out.println(id+","+name+","+mobile+","+address);
}
System.out.println("查询失败");
} catch (SQLException e) {
e.printStackTrace();
}
},id);
break;
}
default:
System.out.println("I'm Sorry,there is not the "+option+" option,please try again.");
}
}
}
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