java连mysql错误

import  java.io.*;
import  java.util.*;
import  java.sql.*;public class ConMysql{ public static void main(String []args) throws IOException{
try{
Connection con;
Statement stmt;
ResultSet rs; Class.forName("com.mysql.jdbc.Driver");
DriverManager.registerDriver(new com.mysql.jdbc.Driver());
String dburl = "jdbc:mysql://localhost:3306/BookDB?useUnicode=true&characterEncoding=GB2312";
String dbUser="dbuser";
String dbPwd="1234";
con = java.sql.DriverManager.getConnection(dburl,dbUser,dbPwd); stmt = con.createStatement();
rs = stmt.executeQuery("select id,name,title,price from books"); while(rs.next()){
String col1 = rs.getString(1);
String col2 = rs.getString(2);
String col3 = rs.getString(3);
float col4 = rs.getFloat(4);
System.out.println(col1+" "+col2+" "+col3+" "+col4+" ");
} rs.close();
stmt.close();
con.close();
}
catch(Exception e){
System.out.println(e.getMessage());
} }}
环境变量都已经配置好了，驱动也加入classpath里了。javac ConMysql.java 成功java ConMysql 出现下面错误：D:\>java ConMysql
Communication link failure: java.io.IOException, underlying cause: Unexpected en
d of input stream** BEGIN NESTED EXCEPTION **java.io.IOException
MESSAGE: Unexpected end of input streamSTACKTRACE:java.io.IOException: Unexpected end of input stream
        at com.mysql.jdbc.MysqlIO.readPacket(MysqlIO.java:1096)
        at com.mysql.jdbc.MysqlIO.doHandshake(MysqlIO.java:626)
        at com.mysql.jdbc.Connection.createNewIO(Connection.java:1562)
        at com.mysql.jdbc.Connection.<init>(Connection.java:491)
        at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java
:346)
        at java.sql.DriverManager.getConnection(Unknown Source)
        at java.sql.DriverManager.getConnection(Unknown Source)
        at ConMysql.main(ConMysql.java:21)
** END NESTED EXCEPTION **