javaJDBC工具类

package jdbc01;

import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.util.Properties;
public class jdbcTool {//连接数据库和关闭流的工具类
    public Connection connect() throws IOException, SQLException {
        Properties properties = new Properties();
        properties.load(new FileInputStream("mysql02.properties"));
        String url = properties.getProperty("url");
        String user = properties.getProperty("user");
        String password = properties.getProperty("password");
        Connection connection = DriverManager.getConnection(url,user,password);
        return connection;
    }
    public void ShutDown(Connection connection) throws SQLException {
        connection.close();
    }
}

package jdbc01;

import java.io.FileNotFoundException;
import java.io.IOException;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.SQLException;
import java.util.Scanner;

public class jdbcText {//工具类练习
    public static void main(String[] args) throws SQLException, IOException {
        Scanner input = new Scanner(System.in);
        jdbcTool jdbcTool = new jdbcTool();
        Connection connect = jdbcTool.connect();
        System.out.println("请输入要删除的用户名：");
        String name = input.nextLine();
        String sql = "delete  from admin where name=?";
        PreparedStatement preparedStatement = connect.prepareStatement(sql);
        preparedStatement.setString(1,name);
        int j = preparedStatement.executeUpdate();
        System.out.println(j>0?"删除成功":"删除失败");
        jdbcTool.ShutDown(connect);
    }
}

基础内容就剩去一个连接过程

package jdbc01;

import com.alibaba.druid.pool.DruidDataSourceFactory;

import javax.sql.DataSource;
import java.io.FileInputStream;
import java.io.IOException;
import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.Properties;

public class jdbcUtil {//德鲁伊工具类
    private static DataSource ds;
    static {
        Properties properties = new Properties();
        try {
            properties.load(new FileInputStream("src\\druid.properties"));
            ds= DruidDataSourceFactory.createDataSource(properties);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
  //编写方法
    public static Connection getConnection() throws SQLException {
        return ds.getConnection();
    }
    //编写关闭连接，不是直接关闭而是把连接放回连接池
    public static void close(ResultSet resultSet, Statement statement,Connection connection){
        try {
            if(resultSet!=null){
                resultSet.close();
            }
            if(statement!=null){
                statement.close();
            }
            if(connection!=null){
                connection.close();
            }
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }
}