briup_JDBC_自建工具类

1.操作的环境 STS,mysql,oracle

orcle 所操作的数据库名为 ORCL 表为 m_stu

表结构如下

 mysql  的表为：my_stu

 表结构如下

 工具类完整代码

package com.briup.jdbc;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;

import com.mysql.jdbc.PreparedStatement;
import com.sun.javafx.geom.AreaOp.AddOp;

public class jdbcUtils {
    // 获取连接
    public static Connection getConnection(String str) {

        if ("mysql".equals(str)) {
            try {
                Class.forName("com.mysql.jdbc.Driver");
                String url = "jdbc:mysql://127.0.0.1:3306/my_database?characterEncoding=UTF-8";
                String username = "root";
                String password = "yue170305";
                try {
                    Connection conn = DriverManager.getConnection(url, username, password);
                    System.out.println("连接到mysql数据库");
                    return conn;
                } catch (SQLException e) {
                    e.printStackTrace();
                }
            } catch (ClassNotFoundException e) {
                e.printStackTrace();
            }

        }
        if ("oracle".equals(str)) {
            try {
                Class.forName("oracle.jdbc.driver.OracleDriver");
                String url = "jdbc:oracle:thin:@localhost:1521:ORCL";
                String username = "scott";
                String password = "yue170305";
                try {
                    Connection conn = DriverManager.getConnection(url, username, password);
                    System.out.println("连接到orcle数据库");
                    return conn;
                } catch (SQLException e) {
                    e.printStackTrace();
                }
            } catch (ClassNotFoundException e) {
                e.printStackTrace();
            }

        }
        return null;

    }

    // 删除数据
    public static void delete(Connection conn, String sql) {
        try {
            Statement statement = conn.createStatement();
            try {
                statement.execute(sql);
                System.out.println("删除数据成功!");
            } catch (Exception e) {
                System.err.println("出现问题了" + e.getMessage());
                e.printStackTrace();
            } finally {
                close(statement, null, conn);
            }
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }
    //修改一条数据
    public static void Update(Connection conn, String sql) {
        try {
            Statement statement = conn.createStatement();
            try {
                statement.execute(sql);
                System.out.println("修改数据成功");
            } catch (Exception e) {
                System.err.println("出现问题了" + e.getMessage());
                e.printStackTrace();
            } finally {
                close(statement, null, conn);
            }

        } catch (SQLException e) {
            e.printStackTrace();
        }
    }
    //查询记录
    public static void select(Connection conn, String sql) {
            try {
                Statement statement = conn.createStatement();
                ResultSet res = statement.executeQuery(sql);
                while(res.next()) {
                    int id=res.getInt("id");
                    String name=res.getString("name");
                    int age=res.getInt("age");
                    String sex=res.getString("sex");
                    System.out.println("id="+id+","+"name="+name+","+"age="+age+","+"sex="+sex);
                }
            } catch (SQLException e) {
                e.printStackTrace();
            }finally {
                close(null, null, conn);
            }
        
    }
    // 添加一条数据
    public static void add(Connection conn, String sql) {
        try {
            Statement statement = conn.createStatement();
            try {
                statement.execute(sql);
                System.out.println("插入数据成功!");
            } catch (Exception e) {
                System.err.println("出现问题了" + e.getMessage());
                e.printStackTrace();
            } finally {
                close(statement, null, conn);
            }

        } catch (SQLException e) {
            e.printStackTrace();
        }
    }
    
    // 关闭连接
    public static void close(Statement st, ResultSet rs, Connection conn) {
        if (st != null) {
            try {
                st.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
        if (rs != null) {
            try {
                rs.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
        if (conn != null) {
            try {
                conn.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }

    }
    
}

测试类代码

package com.briup.jdbc;

import java.sql.Connection;

public class Test {
    public static void main(String[] args) {
        //连接到mysql数据库
//        Connection connection = jdbcUtils.getConnection("mysql");
//        String sql="insert into my_stu values(8,'dadaming',108,'m')";
        //jdbcUtils.add(connection, sql);
        
        //删除数据(mysql)
//        String sql2="delete from my_stu where id=1";
//        jdbcUtils.delete(connection, sql2);
        
        //连接到oracle数据库
        Connection connection2 = jdbcUtils.getConnection("oracle");
        String sql1="insert into m_stu values(7,'lifd',15,'n')";
        String sql2="delete from m_stu where id=1";
        String sql3=" update m_stu "
                    + "set name='李悦'"
                    + "where id=1";
        String sql4="select * from m_stu";
        //jdbcUtils.add(connection2, sql1);
        //jdbcUtils.delete(connection2, sql2);
        //jdbcUtils.Update(connection2, sql3);
        jdbcUtils.select(connection2, sql4);
        
    }
}