mysql-Eclipse用JDBC连接不上MySql，求解决办法

相关mysql视频教程推荐：《mysql教程》

使用JDBC的方法连接不上MySQL，我的网络是校园网，登陆后IP会变化，不知道这个对连接有没有什么影响，用的是mysql 5.6 以前用JDBC连接上过的，但是现在就不行了，不清楚原因，也在网上找过，但是找不到解决的办法，连接的JAR包是mysql-connector-java-5.1.26-bin.jar，请知道的大神解答一下小弟，还有就是使用Oracle用JDBC是连接得上的，使用的地址也是localhost，但是在用JDBC连接数据库查看的时候，在使用preparedStatement返回的genernatekeys无法使用getInt这个方法，所以想用mysql，因为视频教程中也是用MySQL的，并且是能用getInt这是方法的，所以想用mysql，麻烦各位大哥帮帮忙 出现的错误如下：

import java.sql.*;
public class TestMysqlConnection {public static void main (String[] args) {Connection conn = null;try {Class.forName("com.mysql.jdbc.Driver");conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/bbs","root","123456");} catch (ClassNotFoundException e) {e.printStackTrace();} catch (SQLException e) {e.printStackTrace();} finally {try {if(conn != null) {conn.close();conn = null;}} catch (SQLException e) {e.printStackTrace();}}}

错误如下：

com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Communication link failure, message from server: "Can't get hostname for your address"
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
at java.lang.reflect.Constructor.newInstance(Unknown Source)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:411)
at com.mysql.jdbc.Util.getInstance(Util.java:386)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1015)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:989)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:975)
at com.mysql.jdbc.MysqlIO.doHandshake(MysqlIO.java:1112)
at com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2486)
at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2519)
at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2304)
at com.mysql.jdbc.ConnectionImpl.(ConnectionImpl.java:834)
at com.mysql.jdbc.JDBC4Connection.(JDBC4Connection.java:47)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
at java.lang.reflect.Constructor.newInstance(Unknown Source)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:411)
at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:416)
at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:346)
at java.sql.DriverManager.getConnection(Unknown Source)
at java.sql.DriverManager.getConnection(Unknown Source)
at TestMysqlConnection.main(TestMysqlConnection.java:8)