import java.sql.Connection;import java.sql.DriverManager;import java.sql.PreparedStatement;import java.sql.ResultSet;import java.sql.ResultSetMetaData;public class MysqlTest {	/**	 * @param args	 */	public static void main(String[] args) throws Exception {		Class.forName("com.mysql.jdbc.Driver");		//String url="jdbc:mysql://localhost:3306/mydb?user=******&password=******&useOldAliasMetadataBehavior=true&useUnicode=true&characterEncoding=utf-8&autoReconnect=true&failOverReadOnly=false";		String url="jdbc:mysql://localhost:3306/mydb?user=******&password=******&useUnicode=true&characterEncoding=utf-8&autoReconnect=true&failOverReadOnly=false";		Connection conn = DriverManager.getConnection(url);		PreparedStatement stmt = conn.prepareStatement("select id as myid,name as myname from test");		ResultSet rs = stmt.executeQuery();		ResultSetMetaData rsmd = rs.getMetaData();		String c1 = rsmd.getColumnName(1);		String c2 = rsmd.getColumnName(2);		while(rs.next()){			String id = rs.getString(c1);//报列名找不到异常			String name = rs.getString(c2);			System.out.println(id+"|"+name);		}		System.out.println(conn);		rs.close();		stmt.close();		conn.close();	}}

Exception in thread "main" java.sql.SQLException: Column 'id' not found.	at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:998)	at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:937)	at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:926)	at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:872)	at com.mysql.jdbc.ResultSetImpl.findColumn(ResultSetImpl.java:1073)	at com.mysql.jdbc.ResultSetImpl.getString(ResultSetImpl.java:5212)	at com.bill99.mysql.MysqlTest.main(MysqlTest.java:25)

解决办法：

JDBC URL中增加useOldAliasMetadataBehavior=true参数