异常片断如下：
2014-03-28 08:49:02 ERROR JDBCTransaction(95) - JDBC begin failed
com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: The last packet successfully received from the server was 45,479,352 milliseconds ago.? The last packet sent successfully to the server was 45,479,352 milliseconds ago. is longer than the server configured value of 'wait_timeout'. You should consider either expiring and/or testing connection validity before use in your application, increasing the server configured values for client timeouts, or using the Connector/J connection property 'autoReconnect=true' to avoid this problem.
??????? 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:1116)
??????? at com.mysql.jdbc.MysqlIO.send(MysqlIO.java:3352)
??????? at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:1971)
??????? at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2151)
??????? at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2619)
??????? at com.mysql.jdbc.ConnectionImpl.setAutoCommit(ConnectionImpl.java:4997)
??????? at org.apache.commons.dbcp.DelegatingConnection.setAutoCommit(DelegatingConnection.java:331)
??????? at org.apache.commons.dbcp.PoolingDataSource$PoolGuardConnectionWrapper.setAutoCommit(PoolingDataSource.java:317)
?
??????? at org.hibernate.transaction.JDBCTransaction.begin(JDBCTransaction.java:91)
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解决方法：
在初始化数据源时加入重连配置。如下图红色方框中内容所示：
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