Cannot create PoolableConnectionFactory (Communications link_MySQL
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今天在做web项目的时候碰到了这样的一个异常：
Caused by: java.lang.RuntimeException: org.apache.tomcat.dbcp.dbcp.SQLNestedException: Cannot create PoolableConnectionFactory (Communications link failureThe last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.) at edu.gzucm.yjsglxt.base.util.TimeSetUtils.getTimeSets(TimeSetUtils.java:52) at edu.gzucm.yjsglxt.base.util.TimeSetUtils.<clinit>(TimeSetUtils.java:22) ... 3 moreCaused by: org.apache.tomcat.dbcp.dbcp.SQLNestedException: Cannot create PoolableConnectionFactory (Communications link failureThe last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.) at org.apache.tomcat.dbcp.dbcp.BasicDataSource.createPoolableConnectionFactory(BasicDataSource.java:1549) at org.apache.tomcat.dbcp.dbcp.BasicDataSource.createDataSource(BasicDataSource.java:1388) at org.apache.tomcat.dbcp.dbcp.BasicDataSource.getConnection(BasicDataSource.java:1044) at edu.gzucm.yjsglxt.base.util.TimeSetUtils.getTimeSets(TimeSetUtils.java:32) ... 4 moreCaused by: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failureThe 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(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:407) at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1116) at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:346) at com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2334) at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2371) at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2163) at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:794) at com.mysql.jdbc.JDBC4Connection.<init>(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:407) at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:378) at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:305) at org.apache.tomcat.dbcp.dbcp.DriverConnectionFactory.createConnection(DriverConnectionFactory.java:38) at org.apache.tomcat.dbcp.dbcp.PoolableConnectionFactory.makeObject(PoolableConnectionFactory.java:582) at org.apache.tomcat.dbcp.dbcp.BasicDataSource.validateConnectionFactory(BasicDataSource.java:1556) at org.apache.tomcat.dbcp.dbcp.BasicDataSource.createPoolableConnectionFactory(BasicDataSource.java:1545) ... 7 moreCaused by: java.net.ConnectException: Connection refused: connect at java.net.PlainSocketImpl.socketConnect(Native Method) at java.net.PlainSocketImpl.doConnect(Unknown Source) at java.net.PlainSocketImpl.connectToAddress(Unknown Source) at java.net.PlainSocketImpl.connect(Unknown Source) at java.net.SocksSocketImpl.connect(Unknown Source) at java.net.Socket.connect(Unknown Source) at java.net.Socket.connect(Unknown Source) at java.net.Socket.<init>(Unknown Source) at java.net.Socket.<init>(Unknown Source) at com.mysql.jdbc.StandardSocketFactory.connect(StandardSocketFactory.java:254) at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:295) ... 23 more2012-2-19 15:35:27 edu.gzucm.yjsglxt.base.util.InitInfoUtil <clinit>严重: nullorg.apache.tomcat.dbcp.dbcp.SQLNestedException: Cannot create PoolableConnectionFactory (Communications link failureThe last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.) at org.apache.tomcat.dbcp.dbcp.BasicDataSource.createPoolableConnectionFactory(BasicDataSource.java:1549) at org.apache.tomcat.dbcp.dbcp.BasicDataSource.createDataSource(BasicDataSource.java:1388) at org.apache.tomcat.dbcp.dbcp.BasicDataSource.getConnection(BasicDataSource.java:1044) at edu.gzucm.yjsglxt.base.util.DataSourceUtil.getConnection(DataSourceUtil.java:67) at edu.gzucm.yjsglxt.base.util.InitInfoUtil.<clinit>(InitInfoUtil.java:265) at edu.gzucm.yjsglxt.base.filter.PrepareFilter.init(PrepareFilter.java:116) at org.apache.catalina.core.ApplicationFilterConfig.initFilter(ApplicationFilterConfig.java:273) at org.apache.catalina.core.ApplicationFilterConfig.getFilter(ApplicationFilterConfig.java:254) at org.apache.catalina.core.ApplicationFilterConfig.setFilterDef(ApplicationFilterConfig.java:372) at org.apache.catalina.core.ApplicationFilterConfig.<init>(ApplicationFilterConfig.java:98) at org.apache.catalina.core.StandardContext.filterStart(StandardContext.java:4584) at org.apache.catalina.core.StandardContext$2.call(StandardContext.java:5262) at org.apache.catalina.core.StandardContext$2.call(StandardContext.java:5257) at java.util.concurrent.FutureTask$Sync.innerRun(Unknown Source) at java.util.concurrent.FutureTask.run(Unknown Source) at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(Unknown Source) at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source) at java.lang.Thread.run(Unknown Source)Caused by: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failureThe 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(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:407) at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1116) at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:346) at com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2334) at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2371) at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2163) at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:794) at com.mysql.jdbc.JDBC4Connection.<init>(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:407) at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:378) at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:305) at org.apache.tomcat.dbcp.dbcp.DriverConnectionFactory.createConnection(DriverConnectionFactory.java:38) at org.apache.tomcat.dbcp.dbcp.PoolableConnectionFactory.makeObject(PoolableConnectionFactory.java:582) at org.apache.tomcat.dbcp.dbcp.BasicDataSource.validateConnectionFactory(BasicDataSource.java:1556) at org.apache.tomcat.dbcp.dbcp.BasicDataSource.createPoolableConnectionFactory(BasicDataSource.java:1545) ... 17 moreCaused by: java.net.ConnectException: Connection refused: connect at java.net.PlainSocketImpl.socketConnect(Native Method) at java.net.PlainSocketImpl.doConnect(Unknown Source) at java.net.PlainSocketImpl.connectToAddress(Unknown Source) at java.net.PlainSocketImpl.connect(Unknown Source) at java.net.SocksSocketImpl.connect(Unknown Source) at java.net.Socket.connect(Unknown Source) at java.net.Socket.connect(Unknown Source) at java.net.Socket.<init>(Unknown Source) at java.net.Socket.<init>(Unknown Source) at com.mysql.jdbc.StandardSocketFactory.connect(StandardSocketFactory.java:254) at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:295) ... 33 more2012-2-19 15:35:27 org.apache.coyote.AbstractProtocol start信息: Starting ProtocolHandler ["http-bio-8080"]2012-2-19 15:35:27 org.apache.coyote.AbstractProtocol start信息: Starting ProtocolHandler ["ajp-bio-8009"]2012-2-19 15:35:27 org.apache.catalina.startup.Catalina start信息: Server startup in 2983 ms
我知道是连接数据库的时候出现了错误，我检查了我的tomcat的配置文件context.xml文件
配置如下：
1 <?xml version="1.0" encoding="UTF-8"?><br /> 2 <!--<br /> 3 Licensed to the Apache Software Foundation (ASF) under one or more<br /> 4 contributor license agreements. See the NOTICE file distributed with<br /> 5 this work for additional information regarding copyright ownership.<br /> 6 The ASF licenses this file to You under the Apache License, Version 2.0<br /> 7 (the "License"); you may not use this file except in compliance with<br /> 8 the License. You may obtain a copy of the License at<br /> 9 <br />10 http://www.apache.org/licenses/LICENSE-2.0<br />11 <br />12 Unless required by applicable law or agreed to in writing, software<br />13 distributed under the License is distributed on an "AS IS" BASIS,<br />14 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.<br />15 See the License for the specific language governing permissions and<br />16 limitations under the License.<br />17 --><!-- The contents of this file will be loaded for each web application --><Context><br />18 <br />19 <!-- Default set of monitored resources --><br />20 <WatchedResource>WEB-INF/web.xml</WatchedResource><br />21 <br />22 <!-- Uncomment this to disable session persistence across Tomcat restarts --><br />23 <!--<br />24 <Manager pathname="" /><br />25 --><br />26 <br />27 <!-- Uncomment this to enable Comet connection tacking (provides events<br />28 on session expiration as well as webapp lifecycle) --><br />29 <!--<br />30 <Valve className="org.apache.catalina.valves.CometConnectionManagerValve" /><br />31 --><br />32 <Resource auth="Container" <br />33 driverClassName="com.mysql.jdbc.Driver" <br />34 maxActive="100" <br />35 maxIdle="30" <br />36 maxWait="10000" <br />37 name="jdbc/mysql" <br />38 password="root" <br />39 type="javax.sql.DataSource" <br />40 url="jdbc:mysql:///yjsglxt?characterEncoding=UTF-8" <br />41 username="root"/><br />42 </Context>
查了一下，才发现原来是url这里有问题：
1 url="jdbc:mysql:///yjsglxt?characterEncoding=UTF-8"
应该改成：
1 url="jdbc:mysql://localhost:3306/yjsglxt?characterEncoding=UTF-8"
这样做了以后，再次运行一下项目，嘿嘿，可以了……………………
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