JDBC模板

import java.sql.*;

public class TestJDBC {

	public static void main(String[] args) throws Exception{
		//1. Load the Driver
		//->1 Class.forName()|Class.forNmae().newInstance()|new DriverName()
		//->2 实例化时自动向DriverManager注册,不需要显示调用DriverManager.registerDriver方法
		Class.forName("oracle.jdbc.driver.OracleDriver");
		//new oracle.jdbc.driver.OracleDriver();
		
		//2. Connect to the DataBase
		//-> DriverManager.getConnection()
		Connection conn=DriverManager.getConnection("jdbc:oracle:thin:@127.0.0.1:1522:ORCL", "scott","tiger");
		
		//3. Execute the SQL
		//->1 Connection.createStatement()
		//->2 Statement.executeQuery()
		//->3 Statement.executeUpdate()
		Statement stat=conn.createStatement();
		ResultSet rs=stat.executeQuery("select * from emp");
		
		//4. Retrieve the result data
		//-> 循环取得结果 while(rs.next())
		while(rs.next()) {
			
		//5. Show the result data
		//->将数据库中的各种烈性转换为Java中的类型(getXXX)方法
			System.out.println(rs.getString("ENAME"));
			System.out.println(rs.getString("JOB"));
		}
		
		//6.Close
		//-> close the ResultSet/ close the statement /close the connection
		rs.close();
		stat.close();
		conn.close();
	}

}

下面是mysql时的情况，稍微一点点不同。

Class.forName("com.mysql.jdbc.Driver");
		Connection conn=DriverManager.getConnection("jdbc:mysql://localhost:3306/test");
		PreparedStatement pstat=conn.prepareStatement("select * from member where mid=?");
		pstat.setString(1, id);
		ResultSet rs=pstat.executeQuery();
		if(rs.next()) {
			rs.close();
			conn.close();
			return "false";
		}

获取mysql端口号的方法：

mysql> show variables like 'port';
+---------------+-------+
| Variable_name | Value |
+---------------+-------+
| port          | 3306  |
+---------------+-------+
1 row in set (0.00 sec)

mysql>