mysql-Eclipse用JDBC连接不上MySql,求解决办法
mysqljavaeclipse
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)

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