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java-com.mysql.jdbc.exceptions.jdbc4.CommunicationsException:通讯链接

这个问题已经在这里有了答案:            >            com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure                                    33个
我正在使用Mac OS X Lion 10.8版.我通过XAMPP安装了MysqL.并且我已经将MysqL和jdbc驱动程序(5.1.22)添加到了我的类路径中.以下简单代码无法正常工作:

package learning.database;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.sqlException;
import java.sql.Statement;

public class Simple {

Connection getConnection() throws sqlException{
String url = "jdbc:MysqL://localhost/";
return DriverManager.getConnection(url, "username", "password");
}

void createDatabase(String database, Connection conn) throws sqlException{
Statement stmt = null;
try {
stmt = conn.createStatement();
stmt.executeUpdate("drop database if exists "+database);
stmt.executeUpdate("create database "+database);
}finally {
if(null != stmt)
stmt.close();
}
}

public static void main(String args[]) throws Exception{
String school = "school";
Classroom cr = new Classroom();
Connection conn = cr.getConnection();
cr.createDatabase(school, conn);
}
}

运行代码时,出现以下错误

Exception in thread "main" com.MysqL.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure

The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27)
at java.lang.reflect.Constructor.newInstance(Constructor.java:513)
at com.MysqL.jdbc.Util.handleNewInstance(Util.java:411)
at com.MysqL.jdbc.sqlError.createCommunicationsException(sqlError.java:1117)
at com.MysqL.jdbc.MysqLIO.<init>(MysqLIO.java:350)
at com.MysqL.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2408)
at com.MysqL.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2445)
at com.MysqL.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2230)
at com.MysqL.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:813)
at com.MysqL.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:47)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27)
at java.lang.reflect.Constructor.newInstance(Constructor.java:513)
at com.MysqL.jdbc.Util.handleNewInstance(Util.java:411)
at com.MysqL.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:399)
at com.MysqL.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:334)
at java.sql.DriverManager.getConnection(DriverManager.java:582)
at java.sql.DriverManager.getConnection(DriverManager.java:185)
at learning.database.Classroom.getConnection(Classroom.java:43)
at learning.database.Simple.main(Simple.java:33)
Caused by: java.net.ConnectException: Connection refused
at java.net.PlainSocketImpl.socketConnect(Native Method)
at java.net.PlainSocketImpl.doConnect(PlainSocketImpl.java:351)
at java.net.PlainSocketImpl.connectToAddress(PlainSocketImpl.java:213)
at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:200)
at java.net.socksSocketImpl.connect(SocksSocketImpl.java:432)
at java.net.socket.connect(Socket.java:529)
at java.net.socket.connect(Socket.java:478)
at java.net.socket.<init>(Socket.java:375)
at java.net.socket.<init>(Socket.java:218)
at com.MysqL.jdbc.StandardSocketFactory.connect(StandardSocketFactory.java:259)
at com.MysqL.jdbc.MysqLIO.<init>(MysqLIO.java:300)
... 16 more

有谁知道如何解决这个问题?

解决方法:

我终于弄明白了.感谢Max和Yogendra发布.
问题出在我的XAMPP配置上.要解决此问题,我做了如下操作:

-   sudo vi /Applications/XAMPP/etc/my.cnf 
⁃   scroll down to `skip-networking`
⁃   comment it out by changing it to `#skip-networking`
⁃   save the changes.
⁃   restart MysqL from XAMPP Console

然后我运行我的代码,一切都很好!

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