java连接mysql

import java.sql.DriverManager;
import java.sql.ResultSet;

import com.mysql.jdbc.Connection;
import com.mysql.jdbc.Statement;


public class JDBCtest {

    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        
        // 声明变量，使用，而后关闭
        Connection conn = null;        //数据库连接
        Statement stmt = null;         //数据库表达式
        ResultSet rs = null;             //结果集
        
        try {
             // 1. 注册驱动
             Class.forName("com.mysql.jdbc.Driver");
            //2. 获取数据库的连接
            String url="jdbc:mysql://localhost:3306/test";
            String user="root";
            String password="root";
         conn = (Connection)DriverManager.getConnection(url, user, password);
            //3. 获取表达式
            stmt = (Statement)conn.createStatement();
            if(conn!=null)System.out.println("连接成功！");
                // 插入数据
            stmt.executeUpdate("insert into Student (username, password, age) values ('zhangsan','1234',20)");
            
            //4. 执行SQL
            rs = stmt.executeQuery("select * from Student");
            
            //5. 现实结果集里面的数据
            while(rs.next()) {
              //  System.out.println("编号=" + rs.getInt(1));
                System.out.println("姓名=" + rs.getString("username"));
                System.out.println("密码=" + rs.getString("password"));
                System.out.println("年龄=" + rs.getString("age"));
                System.out.println("---------------");
            }
        }
        catch (Exception ex) {
            ex.printStackTrace();
        }
        finally {
            try {
                if(rs != null) {
                    rs.close();
                }
                if(stmt != null) {
                    stmt.close();
                }
                if(conn != null) {
                    conn.close();
                }
            } catch(Exception ex) {
                ex.printStackTrace();
            }
        }
    }
}

mysql> create table Student(
    -> username varchar(20),
    -> password varchar(30),
    -> age int);
Query OK, 0 rows affected (0.08 sec)

mysql> insert into Student (username, password, age) values ('张三','1234',20);
Query OK, 1 row affected (0.03 sec)