看视频发现自己有很多错，改正一下。
一、代码实现
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package friendscaozuo.mysql; import java.sql.DriverManager; import java.sql.ResultSet; import java.sql.SQLException; import com.mysql.jdbc.Connection; import com.mysql.jdbc.Statement; public class jdbctest { private static final String url = "jdbc:mysql://127.0.0.1:3306/testmysql"; private static final String user = "godlikexie"; private static final String password = "doudou1688"; public static void main(String[] args) throws ClassNotFoundException/*SQLException*/, SQLException { // TODO Auto-generated method stub Class.forName("com.mysql.jdbc.Driver");//一开始我是真的不知道这行东西是怎么打出来的 Connection conn = (Connection) DriverManager.getConnection(url, user, password); //com.mysql.jdbc.Driver driver = new com.mysql.jdbc.Driver(); 这样也是可以的，待研究 /*System.out.println("Success loading Mysql Driver!"); java.sql.Connection connection = DriverManager.getConnection("jdbc:mysql://localhost:3306/test","root","root"); System.out.println("Success connect Mysql server!"); */ Statement stmt = (Statement) conn.createStatement(); ResultSet rs = stmt.executeQuery("select user_name,age from myfriend"); while(rs.next()) { System.out.println(rs.getString("user_name")+","+rs.getInt("age")); } } } |
简单的程序,逐行打印出了两个字段中的内容:
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Statement stmt = (Statement) conn.createStatement(); ResultSet rs = stmt.executeQuery("select user_name,age from myfriend"); while(rs.next()) { System.out.println(rs.getString("user_name")+","+rs.getInt("age")); } |
二、总结
问题也比较明显，开启mysql链接后没有关闭，容易造成链接泄露，以后需要多加注意。