JAVA使用JDBC连接MySQL数据库

1. 在 pom.xml 文件中加入依赖

    <dependency>
    <groupId>mysql</groupId>
    <artifactId>mysql-connector-java</artifactId>
    <version>6.0.2</version>

2. 编写一个连接、关闭、查询数据库的类

    package com.hu.demo;  
      
    import java.sql.Connection;  
    import java.sql.DriverManager;  
    import java.sql.PreparedStatement;  
    import java.sql.SQLException;  
      
    public class DBHelper {  
        public static final String url = "jdbc:mysql://127.0.0.1/student";  
        public static final String name = "com.mysql.jdbc.Driver";  
        public static final String user = "root";  
        public static final String password = "root";  
      
        public Connection conn = null;  
        public PreparedStatement pst = null;  
      
        public DBHelper(String sql) {  
            try {  
                Class.forName(name);//指定连接类型  
                conn = DriverManager.getConnection(url, user, password);//获取连接  
                pst = conn.prepareStatement(sql);//准备执行语句  
            } catch (Exception e) {  
                e.printStackTrace();  
            }  
        }  
      
        public void close() {  
            try {  
                this.conn.close();  
                this.pst.close();  
            } catch (SQLException e) {  
                e.printStackTrace();  
            }  
        }  
    }  

3. 编写一个 Demo 类来测试下

    package com.hu.demo;  
      
    import java.sql.ResultSet;  
    import java.sql.SQLException;  
      
    public class Demo {  
      
        static String sql = null;  
        static DBHelper db1 = null;  
        static ResultSet ret = null;  
      
        public static void main(String[] args) {  
            sql = "select *from stuinfo";//SQL语句  
            db1 = new DBHelper(sql);//创建DBHelper对象  
      
            try {  
                ret = db1.pst.executeQuery();//执行语句，得到结果集  
                while (ret.next()) {  
                    String uid = ret.getString(1);  
                    String ufname = ret.getString(2);  
                    String ulname = ret.getString(3);  
                    String udate = ret.getString(4);  
                    System.out.println(uid + "	" + ufname + "	" + ulname + "	" + udate );  
                }//显示数据  
                ret.close();  
                db1.close();//关闭连接  
            } catch (SQLException e) {  
                e.printStackTrace();  
            }  
        }  
      
    }