mysql数据库连接池的问题
java.sql.SQLException: unable to get a connection from pool of a PoolingDataSource containing an XAPool of resource jdbc/testDS1 with 0 connection(s) (0 still available)
at bitronix.tm.resource.jdbc.PoolingDataSource.getConnection(PoolingDataSource.java:201)
at com.sample.testDB.main(testDB.java:106)
Caused by: 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:409)
at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1118)
at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:343)
at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2308)
at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2122)
at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:774)
at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:49)
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:409)
at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:375)
at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:289)
at com.mysql.jdbc.jdbc2.optional.MysqlDataSource.getConnection(MysqlDataSource.java:442)
at com.mysql.jdbc.jdbc2.optional.MysqlDataSource.getConnection(MysqlDataSource.java:140)
at com.mysql.jdbc.jdbc2.optional.MysqlDataSource.getConnection(MysqlDataSource.java:110)
at com.mysql.jdbc.jdbc2.optional.MysqlXADataSource.getXAConnection(MysqlXADataSource.java:50)
at bitronix.tm.resource.jdbc.PoolingDataSource.createPooledConnection(PoolingDataSource.java:274)
at bitronix.tm.resource.common.XAPool.createPooledObject(XAPool.java:283)
at bitronix.tm.resource.common.XAPool.grow(XAPool.java:400)
at bitronix.tm.resource.common.XAPool.getInPool(XAPool.java:379)
at bitronix.tm.resource.common.XAPool.getConnectionHandle(XAPool.java:123)
at bitronix.tm.resource.common.XAPool.getConnectionHandle(XAPool.java:91)
at bitronix.tm.resource.jdbc.PoolingDataSource.getConnection(PoolingDataSource.java:197)
... 1 more
Caused by: java.net.UnknownHostException: mysqlserver
at java.net.Inet4AddressImpl.lookupAllHostAddr(Native Method)
at java.net.InetAddress$1.lookupAllHostAddr(InetAddress.java:849)
at java.net.InetAddress.getAddressFromNameService(InetAddress.java:1200)
at java.net.InetAddress.getAllByName0(InetAddress.java:1153)
at java.net.InetAddress.getAllByName(InetAddress.java:1083)
at java.net.InetAddress.getAllByName(InetAddress.java:1019)
at com.mysql.jdbc.StandardSocketFactory.connect(StandardSocketFactory.java:246)
at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:292)
... 23 more
帮看看怎么解决

------解决方案--------------------
贴点代码吧 这么看不好看
------解决方案--------------------
unable to get a connection from pool of a PoolingDataSource containing an XAPool of resource jdbc/testDS1 with 0 connection(s) (0 still available)
就是说不能从连接池jdbc/testDS1里面获得连接
我的异常网推荐解决方案：The driver has not received any packets from the server.,http://www.myexception.cn/j2ee/345243.html