一个最简单的JDBC程序的问题
package zixue.jdbc;

import java.sql.Connection;

import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Statement;
import java.sql.SQLException;

public class Base {


static void test() throws SQLException,ClassNotFoundException{
//注册驱动
Class.forName("com.mysql.jdbc.Driver");
//DriverManager.registerDriver(new com.mysql.jdbc.Driver());

//建立连接
Connection conn = DriverManager.getConnection(
"jdbc:mysql://localhost:3306/jdbc","root","woaiyan");

//创建语句
Statement st = conn.createStatement();

//执行语句
ResultSet rs = st.executeQuery("select * from user");

//处理结果
while(rs.next()){
System.out.print(rs.getObject(1)+"\t"+rs.getObject(2)+
"\t"+rs.getObject(3)+"\t");
}
//释放资源
rs.close();
st.close();
conn.close();
}
}


这是我的代码
驱动也有加进去
但是每次运行都显示不出查询的结果
控制台的信息是：
<ConnectionProperties>
<PropertyCategory name="Connection/Authentication">
<Property name="user" required="No" default="" sortOrder="-2147483647" since="all versions">
The user to connect as
</Property>
<Property name="password" required="No" default="" sortOrder="-2147483646" since="all versions">
The password to use when connecting
</Property>
<Property name="socketFactory" required="No" default="com.mysql.jdbc.StandardSocketFactory" sortOrder="4" since="3.0.3">
The name of the class that the driver should use for creating socket connections to the server. This class must implement the interface 'com.mysql.jdbc.SocketFactory' and have public no-args constructor.
</Property>
。。。。（还有很多）


我研究了半天了 换过SQL 换过驱动 也是一样的~
还有 我用MySQL的dos界面中查询可以查出我得 JDBC数据库中得JDBC表

[解决办法]
你执行下面的代码看看控制台输出什么异常或者rs为空的信息么？

Java code

import java.sql.Connection;import java.sql.DriverManager;import java.sql.ResultSet;import java.sql.Statement;import java.sql.SQLException;public class Base {    static void test() throws SQLException,ClassNotFoundException{//注册驱动        Class.forName("com.mysql.jdbc.Driver");//DriverManager.registerDriver(new com.mysql.jdbc.Driver());//建立连接        Connection conn = DriverManager.getConnection(                "jdbc:mysql://localhost:3306/jdbc","root","woaiyan");//创建语句        Statement st = conn.createStatement();//执行语句        ResultSet rs = st.executeQuery("select * from user");//处理结果        if(rs==null){             System.out.println("查询结果为空");        }        while(rs.next()){            System.out.print(rs.getObject(1)+"\t"+rs.getObject(2)+                    "\t"+rs.getObject(3)+"\t");        }//释放资源        rs.close();        st.close();        conn.close();    }    public static void main(String[] args){           try{              test();           }catch(Exception e){                e.printStackTrace();           }    }}