maven实现学生管理系统

技术2023-05-31 72

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); return； } 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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