转载：https://www.cnblogs.com/littlehb/p/9207293.html
报错信息：
The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.
at com.tomymap.galaxy.virgo.util.DbService.getConnection(DbService.java:66)
at com.tomymap.galaxy.virgo.util.DbService.getConnection(DbService.java:46)
at com.tomymap.galaxy.virgo.dao.PNNDao.getConnection(PNNDao.java:51)
at com.tomymap.galaxy.virgo.dao.DaoBase.executeUpdate(DaoBase.java:69)
at com.tomymap.galaxy.virgo.dao.PNNDao.updatePNNRelation(PNNDao.java:161)
at com.tomymap.galaxy.virgo.pnn.PyramidNeuralNetwork.buildPNNRelations(PyramidNeuralNetwork.java:400)
at com.tomymap.galaxy.virgo.pnn.PyramidNeuralNetwork.incrementalGenPNN(PyramidNeuralNetwork.java:144)
at com.tomymap.galaxy.virgo.pnn.PyramidNeuralNetwork.main(PyramidNeuralNetwork.java:410)
解决方法：
（1）使用JDBC URL中使用autoReconnect属性，url添加
autoReconnect=true&failOverReadOnly=false&maxReconnects=10
（2） 修改MySQL的参数. /etc/my.cnf 添加
[mysqld]
wait_timeout=31536000
interactive_timeout=31536000
（3）重启mysql
service mysql restart