建立了连接池后还是出现内存溢出提示

android应用程序在第一个activity中调用连接池中的连接可以正常访问数据库,访问后也将连接归还到连接池中了,在第二个activity中再次调用连接池中的连接,就出现错误提示。图图片说明

1个回答

这不是内存溢出,你翻译一下:没有调用“close”方法。
不用的socket请手动关闭

问答版主就是牛,从现在起只回论坛,不在踏入问答半步

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内存溢出问题,不知道是哪里出现的问题,怀疑是druid连接池使用不当,求大佬帮忙。

昨晚上出现了两次内存溢出,找不到复现的方法,每次出现内存溢出都不一样,两次都是先出现"Disk Write of"写入磁盘失败错误,然后就是druid获取连接失败,然后报OOM异常,接着linux服务器cpu使用率上涨,一直涨到百分之600满(服务器是6核CPU),第二次的日志看跟第一次出现类似;下面是第一次 日志 2020-03-16 17:39:47 ERROR [DiskStorageFactory.java:495] - Disk Write of mcs_ca92_processor failed: java.lang.OutOfMemoryError: PermGen space 2020-03-16 17:39:47 ERROR [DiskStorageFactory.java:495] - Disk Write of mcs_ca92_processor failed: java.lang.OutOfMemoryError: PermGen space 2020-03-16 17:40:36 INFO [BaseHandler.java:42] - 向解码器推送协议{"topic":"controlProtocol/applyBackPicCtrl/00:00:01:A0:43:74/1c79b3b3-6020-4af7-97ec-a1abd5f0cc07","timeStamp":"1584351636324","msgId":"598577930","videoEnable":0,"picList":[{"level":0,"imageEndY":900,"imageEndX":1600,"blockEndY":900,"blockEndX":1600,"blockStartY":180,"imageStartX":320,"picId":16777400,"imageStartY":180,"blockStartX":320}]} 2020-03-16 17:40:36 ERROR [DiskStorageFactory.java:495] - Disk Write of mcs_pic_layer failed: java.lang.OutOfMemoryError: PermGen space 2020-03-16 17:40:36 ERROR [DiskStorageFactory.java:495] - Disk Write of mcs_pic_layer failed: java.lang.OutOfMemoryError: PermGen space 2020-03-16 17:40:36 INFO [MQTTProtocolHandler.java:89] - 接收到返回协议:{"topic":"reControlProtocol/reApplyBackPicCtrl/1c79b3b3-6020-4af7-97ec-a1abd5f0cc07/00:00:01:A0:43:74","result":"success","timeStamp":"1584351636324","msgId":"598577930","msg":"成功"} 2020-03-16 17:41:36 INFO [BaseHandler.java:42] - 向解码器推送协议{"topic":"controlProtocol/applyBackPicCtrl/00:00:01:A0:43:74/1c79b3b3-6020-4af7-97ec-a1abd5f0cc07","timeStamp":"1584351696340","msgId":"480724569","videoEnable":0,"picList":[{"level":0,"imageEndY":900,"imageEndX":1600,"blockEndY":900,"blockEndX":1600,"blockStartY":180,"imageStartX":320,"picId":16777400,"imageStartY":180,"blockStartX":320}]} 2020-03-16 17:41:36 ERROR [DiskStorageFactory.java:495] - Disk Write of mcs_pic_layer failed: java.lang.OutOfMemoryError: PermGen space 2020-03-16 17:41:36 ERROR [DiskStorageFactory.java:495] - Disk Write of mcs_pic_layer failed: java.lang.OutOfMemoryError: PermGen space 2020-03-16 17:41:36 INFO [MQTTProtocolHandler.java:89] - 接收到返回协议:{"topic":"reControlProtocol/reApplyBackPicCtrl/1c79b3b3-6020-4af7-97ec-a1abd5f0cc07/00:00:01:A0:43:74","result":"success","timeStamp":"1584351696340","msgId":"480724569","msg":"成功"} 2020-03-16 17:42:36 INFO [BaseHandler.java:42] - 向解码器推送协议{"topic":"controlProtocol/applyBackPicCtrl/00:00:01:A0:43:74/1c79b3b3-6020-4af7-97ec-a1abd5f0cc07","timeStamp":"1584351756356","msgId":"2008015594","videoEnable":0,"picList":[{"level":0,"imageEndY":900,"imageEndX":1600,"blockEndY":900,"blockEndX":1600,"blockStartY":180,"imageStartX":320,"picId":33554616,"imageStartY":180,"blockStartX":320}]} 2020-03-16 17:42:36 ERROR [DiskStorageFactory.java:495] - Disk Write of mcs_pic_layer failed: java.lang.OutOfMemoryError: PermGen space 2020-03-16 17:42:36 ERROR [DiskStorageFactory.java:495] - Disk Write of mcs_pic_layer failed: java.lang.OutOfMemoryError: PermGen space 2020-03-16 17:42:36 INFO [MQTTProtocolHandler.java:89] - 接收到返回协议:{"topic":"reControlProtocol/reApplyBackPicCtrl/1c79b3b3-6020-4af7-97ec-a1abd5f0cc07/00:00:01:A0:43:74","result":"success","timeStamp":"1584351756356","msgId":"2008015594","msg":"成功"} 2020-03-16 17:43:36 INFO [BaseHandler.java:42] - 向解码器推送协议{"topic":"controlProtocol/applyBackPicCtrl/00:00:01:A0:43:74/1c79b3b3-6020-4af7-97ec-a1abd5f0cc07","timeStamp":"1584351816372","msgId":"1754653907","videoEnable":0,"picList":[{"level":0,"imageEndY":900,"imageEndX":1600,"blockEndY":900,"blockEndX":1600,"blockStartY":180,"imageStartX":320,"picId":184,"imageStartY":180,"blockStartX":320}]} 2020-03-16 17:43:36 ERROR [DiskStorageFactory.java:495] - Disk Write of mcs_pic_layer failed: java.lang.OutOfMemoryError: PermGen space 2020-03-16 17:43:36 ERROR [DiskStorageFactory.java:495] - Disk Write of mcs_pic_layer failed: java.lang.OutOfMemoryError: PermGen space 2020-03-16 17:43:36 INFO [MQTTProtocolHandler.java:89] - 接收到返回协议:{"topic":"reControlProtocol/reApplyBackPicCtrl/1c79b3b3-6020-4af7-97ec-a1abd5f0cc07/00:00:01:A0:43:74","result":"success","timeStamp":"1584351816372","msgId":"1754653907","msg":"成功"} 2020-03-16 17:44:37 WARN [DruidDataSource.java:1258] - get connection timeout retry : 1 2020-03-16 17:44:38 WARN [DruidDataSource.java:1258] - get connection timeout retry : 1 2020-03-16 17:44:38 WARN [DruidDataSource.java:1258] - get connection timeout retry : 1 2020-03-16 17:44:41 INFO [BaseHandler.java:42] - 向解码器推送协议{"topic":"controlProtocol/applyBackPicCtrl/00:00:01:A0:43:74/1c79b3b3-6020-4af7-97ec-a1abd5f0cc07","timeStamp":"1584351881843","msgId":"327484943","videoEnable":0,"picList":[{"level":0,"imageEndY":900,"imageEndX":1600,"blockEndY":900,"blockEndX":1600,"blockStartY":180,"imageStartX":320,"picId":16777400,"imageStartY":180,"blockStartX":320}]} 2020-03-16 17:44:41 ERROR [DiskStorageFactory.java:495] - Disk Write of mcs_pic_layer failed: java.lang.OutOfMemoryError: PermGen space 2020-03-16 17:44:43 ERROR [DiskStorageFactory.java:495] - Disk Write of mcs_pic_layer failed: java.lang.OutOfMemoryError: PermGen space 2020-03-16 17:44:48 WARN [DruidDataSource.java:1258] - get connection timeout retry : 1 2020-03-16 17:44:48 WARN [DruidDataSource.java:1258] - get connection timeout retry : 1 2020-03-16 17:44:49 INFO [MQTTProtocolHandler.java:89] - 接收到返回协议:{"topic":"reControlProtocol/reApplyBackPicCtrl/1c79b3b3-6020-4af7-97ec-a1abd5f0cc07/00:00:01:A0:43:74","result":"success","timeStamp":"1584351881843","msgId":"327484943","msg":"成功"} 2020-03-16 17:45:02 ERROR [DruidDataSource.java:2469] - create connection SQLException, url: jdbc:mysql://localhost:55060/mcs?useUnicode=true&characterEncoding=utf-8, errorCode 0, state S1000 java.sql.SQLException: java.lang.OutOfMemoryError: PermGen space at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:965) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:898) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:887) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:861) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:878) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:874) at com.mysql.jdbc.Util.handleNewInstance(Util.java:443) at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:385) at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:323) at com.alibaba.druid.pool.DruidAbstractDataSource.createPhysicalConnection(DruidAbstractDataSource.java:1513) at com.alibaba.druid.pool.DruidAbstractDataSource.createPhysicalConnection(DruidAbstractDataSource.java:1578) at com.alibaba.druid.pool.DruidDataSource$CreateConnectionThread.run(DruidDataSource.java:2466) Caused by: java.lang.OutOfMemoryError: PermGen space 2020-03-16 17:45:55 ERROR [DiskStorageFactory.java:495] - Disk Write of mcs_pic_layer failed: java.lang.OutOfMemoryError: PermGen space 2020-03-16 17:45:55 INFO [BaseHandler.java:42] - 向解码器推送协议{"topic":"controlProtocol/applyBackPicCtrl/00:00:01:A0:43:74/1c79b3b3-6020-4af7-97ec-a1abd5f0cc07","timeStamp":"1584351955374","msgId":"690664616","videoEnable":0,"picList":[{"level":0,"imageEndY":900,"imageEndX":1600,"blockEndY":900,"blockEndX":1600,"blockStartY":180,"imageStartX":320,"picId":33554616,"imageStartY":180,"blockStartX":320}]} 2020-03-16 17:45:55 ERROR [DiskStorageFactory.java:495] - Disk Write of mcs_pic_layer failed: java.lang.OutOfMemoryError: PermGen space 2020-03-16 17:46:00 INFO [MQTTProtocolHandler.java:89] - 接收到返回协议:{"topic":"reControlProtocol/reApplyBackPicCtrl/1c79b3b3-6020-4af7-97ec-a1abd5f0cc07/00:00:01:A0:43:74","result":"success","timeStamp":"1584351955374","msgId":"690664616","msg":"成功"} 2020-03-16 17:47:13 INFO [BaseHandler.java:42] - 向解码器推送协议{"topic":"controlProtocol/applyBackPicCtrl/00:00:01:A0:43:74/1c79b3b3-6020-4af7-97ec-a1abd5f0cc07","timeStamp":"1584352033984","msgId":"1701533843","videoEnable":0,"picList":[{"level":0,"imageEndY":900,"imageEndX":1600,"blockEndY":900,"blockEndX":1600,"blockStartY":180,"imageStartX":320,"picId":184,"imageStartY":180,"blockStartX":320}]} 2020-03-16 17:47:13 ERROR [DiskStorageFactory.java:495] - Disk Write of mcs_pic_layer failed: java.lang.OutOfMemoryError: PermGen space 2020-03-16 17:47:14 ERROR [DiskStorageFactory.java:495] - Disk Write of mcs_pic_layer failed: java.lang.OutOfMemoryError: PermGen space 2020-03-16 17:47:19 INFO [MQTTProtocolHandler.java:89] - 接收到返回协议:{"topic":"reControlProtocol/reApplyBackPicCtrl/1c79b3b3-6020-4af7-97ec-a1abd5f0cc07/00:00:01:A0:43:74","result":"success","timeStamp":"1584352033984","msgId":"1701533843","msg":"成功"} 2020-03-16 17:48:48 INFO [BaseHandler.java:42] - 向解码器推送协议{"topic":"controlProtocol/applyBackPicCtrl/00:00:01:A0:43:74/1c79b3b3-6020-4af7-97ec-a1abd5f0cc07","timeStamp":"1584352128999","msgId":"1984150795","videoEnable":0,"picList":[{"level":0,"imageEndY":900,"imageEndX":1600,"blockEndY":900,"blockEndX":1600,"blockStartY":180,"imageStartX":320,"picId":16777400,"imageStartY":180,"blockStartX":320}]} 2020-03-16 17:48:50 ERROR [DiskStorageFactory.java:495] - Disk Write of mcs_pic_layer failed: java.lang.OutOfMemoryError: PermGen space 2020-03-16 17:48:50 INFO [MQTTProtocolHandler.java:89] - 接收到返回协议:{"topic":"reControlProtocol/reApplyBackPicCtrl/1c79b3b3-6020-4af7-97ec-a1abd5f0cc07/00:00:01:A0:43:74","result":"success","timeStamp":"1584352128999","msgId":"1984150795","msg":"成功"} 2020-03-16 17:48:51 ERROR [DiskStorageFactory.java:495] - Disk Write of mcs_pic_layer failed: java.lang.OutOfMemoryError: PermGen space 2020-03-16 17:50:00 INFO [BaseHandler.java:42] - 向解码器推送协议{"topic":"controlProtocol/applyBackPicCtrl/00:00:01:A0:43:74/1c79b3b3-6020-4af7-97ec-a1abd5f0cc07","timeStamp":"1584352200578","msgId":"1977525065","videoEnable":0,"picList":[{"level":0,"imageEndY":900,"imageEndX":1600,"blockEndY":900,"blockEndX":1600,"blockStartY":180,"imageStartX":320,"picId":33554616,"imageStartY":180,"blockStartX":320}]} 2020-03-16 17:50:01 ERROR [DiskStorageFactory.java:495] - Disk Write of mcs_pic_layer failed: java.lang.OutOfMemoryError: PermGen space 2020-03-16 17:50:03 ERROR [DiskStorageFactory.java:495] - Disk Write of mcs_pic_layer failed: java.lang.OutOfMemoryError: PermGen space 2020-03-16 17:50:04 INFO [MQTTProtocolHandler.java:89] - 接收到返回协议:{"topic":"reControlProtocol/reApplyBackPicCtrl/1c79b3b3-6020-4af7-97ec-a1abd5f0cc07/00:00:01:A0:43:74","result":"success","timeStamp":"1584352200578","msgId":"1977525065","msg":"成功"} 2020-03-16 17:51:20 INFO [BaseHandler.java:42] - 向解码器推送协议{"topic":"controlProtocol/applyBackPicCtrl/00:00:01:A0:43:74/1c79b3b3-6020-4af7-97ec-a1abd5f0cc07","timeStamp":"1584352280657","msgId":"1863876211","videoEnable":0,"picList":[{"level":0,"imageEndY":900,"imageEndX":1600,"blockEndY":900,"blockEndX":1600,"blockStartY":180,"imageStartX":320,"picId":184,"imageStartY":180,"blockStartX":320}]} 2020-03-16 17:51:21 ERROR [DiskStorageFactory.java:495] - Disk Write of mcs_pic_layer failed: java.lang.OutOfMemoryError: PermGen space 2020-03-16 17:51:22 ERROR [DiskStorageFactory.java:495] - Disk Write of mcs_pic_layer failed: java.lang.OutOfMemoryError: PermGen space 2020-03-16 17:51:28 INFO [MQTTProtocolHandler.java:89] - 接收到返回协议:{"topic":"reControlProtocol/reApplyBackPicCtrl/1c79b3b3-6020-4af7-97ec-a1abd5f0cc07/00:00:01:A0:43:74","result":"success","timeStamp":"1584352280657","msgId":"1863876211","msg":"成功"} 2020-03-16 17:52:47 ERROR [DiskStorageFactory.java:495] - Disk Write of mcs_pic_layer failed: java.lang.OutOfMemoryError: PermGen space 2020-03-16 17:52:50 ERROR [DiskStorageFactory.java:495] - Disk Write of mcs_pic_layer failed: java.lang.OutOfMemoryError: PermGen space 2020-03-16 17:52:55 INFO [BaseHandler.java:42] - 向解码器推送协议{"topic":"controlProtocol/applyBackPicCtrl/00:00:01:A0:43:74/1c79b3b3-6020-4af7-97ec-a1abd5f0cc07","timeStamp":"1584352373108","msgId":"628094041","videoEnable":0,"picList":[{"level":0,"imageEndY":900,"imageEndX":1600,"blockEndY":900,"blockEndX":1600,"blockStartY":180,"imageStartX":320,"picId":16777400,"imageStartY":180,"blockStartX":320}]} 2020-03-16 17:53:03 INFO [MQTTProtocolHandler.java:89] - 接收到返回协议:{"topic":"reControlProtocol/reApplyBackPicCtrl/1c79b3b3-6020-4af7-97ec-a1abd5f0cc07/00:00:01:A0:43:74","result":"success","timeStamp":"1584352373108","msgId":"628094041","msg":"成功"} 2020-03-16 17:54:00 INFO [BaseHandler.java:42] - 向解码器推送协议{"topic":"controlProtocol/applyBackPicCtrl/00:00:01:A0:43:74/1c79b3b3-6020-4af7-97ec-a1abd5f0cc07","timeStamp":"1584352439640","msgId":"72219615","videoEnable":0,"picList":[{"level":0,"imageEndY":900,"imageEndX":1600,"blockEndY":900,"blockEndX":1600,"blockStartY":180,"imageStartX":320,"picId":33554616,"imageStartY":180,"blockStartX":320}]} 2020-03-16 17:54:00 ERROR [DiskStorageFactory.java:495] - Disk Write of mcs_pic_layer failed: java.lang.OutOfMemoryError: PermGen space 2020-03-16 17:54:03 ERROR [DiskStorageFactory.java:495] - Disk Write of mcs_pic_layer failed: java.lang.OutOfMemoryError: PermGen space 2020-03-16 17:54:09 INFO [MQTTProtocolHandler.java:89] - 接收到返回协议:{"topic":"reControlProtocol/reApplyBackPicCtrl/1c79b3b3-6020-4af7-97ec-a1abd5f0cc07/00:00:01:A0:43:74","result":"success","timeStamp":"1584352439640","msgId":"72219615","msg":"成功"} 2020-03-16 17:55:23 WARN [DruidDataSource.java:1258] - get connection timeout retry : 1 2020-03-16 17:55:23 WARN [DruidDataSource.java:1258] - get connection timeout retry : 1 2020-03-16 17:55:25 ERROR [DiskStorageFactory.java:495] - Disk Write of mcs_pic_layer failed: java.lang.OutOfMemoryError: PermGen space 2020-03-16 17:55:26 ERROR [DiskStorageFactory.java:495] - Disk Write of mcs_pic_layer failed: java.lang.OutOfMemoryError: PermGen space 2020-03-16 17:55:26 INFO [BaseHandler.java:42] - 向解码器推送协议{"topic":"controlProtocol/applyBackPicCtrl/00:00:01:A0:43:74/1c79b3b3-6020-4af7-97ec-a1abd5f0cc07","timeStamp":"1584352526466","msgId":"1473614692","videoEnable":0,"picList":[{"level":0,"imageEndY":900,"imageEndX":1600,"blockEndY":900,"blockEndX":1600,"blockStartY":180,"imageStartX":320,"picId":184,"imageStartY":180,"blockStartX":320}]} 2020-03-16 17:55:36 WARN [DruidDataSource.java:1258] - get connection timeout retry : 1 2020-03-16 17:55:41 ERROR [DruidDataSource.java:2469] - create connection SQLException, url: jdbc:mysql://localhost:55060/mcs?useUnicode=true&characterEncoding=utf-8, errorCode 0, state S1000 java.sql.SQLException: java.lang.OutOfMemoryError: PermGen space at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:965) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:898) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:887) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:861) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:878) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:874) at com.mysql.jdbc.Util.handleNewInstance(Util.java:443) at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:385) at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:323) at com.alibaba.druid.pool.DruidAbstractDataSource.createPhysicalConnection(DruidAbstractDataSource.java:1513) at com.alibaba.druid.pool.DruidAbstractDataSource.createPhysicalConnection(DruidAbstractDataSource.java:1578) at com.alibaba.druid.pool.DruidDataSource$CreateConnectionThread.run(DruidDataSource.java:2466) Caused by: java.lang.OutOfMemoryError: PermGen space 2020-03-16 17:55:42 INFO [MQTTProtocolHandler.java:89] - 接收到返回协议:{"topic":"reControlProtocol/reApplyBackPicCtrl/1c79b3b3-6020-4af7-97ec-a1abd5f0cc07/00:00:01:A0:43:74","result":"success","timeStamp":"1584352526466","msgId":"1473614692","msg":"成功"} 2020-03-16 17:55:48 WARN [DruidDataSource.java:1258] - get connection timeout retry : 1 2020-03-16 17:56:00 WARN [DruidDataSource.java:1258] - get connection timeout retry : 1 2020-03-16 17:56:00 WARN [DruidDataSource.java:1258] - get connection timeout retry : 1 2020-03-16 17:56:02 ERROR [DruidDataSource.java:2469] - create connection SQLException, url: jdbc:mysql://localhost:55060/mcs?useUnicode=true&characterEncoding=utf-8, errorCode 0, state S1000 java.sql.SQLException: java.lang.OutOfMemoryError: PermGen space at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:965) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:898) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:887) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:861) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:878) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:874) at com.mysql.jdbc.Util.handleNewInstance(Util.java:443) at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:385) at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:323) at com.alibaba.druid.pool.DruidAbstractDataSource.createPhysicalConnection(DruidAbstractDataSource.java:1513) at com.alibaba.druid.pool.DruidAbstractDataSource.createPhysicalConnection(DruidAbstractDataSource.java:1578) at com.alibaba.druid.pool.DruidDataSource$CreateConnectionThread.run(DruidDataSource.java:2466) Caused by: java.lang.OutOfMemoryError: PermGen space 2020-03-16 17:56:05 WARN [DruidDataSource.java:1258] - get connection timeout retry : 1 2020-03-16 17:56:06 WARN [SqlExceptionHelper.java:143] - SQL Error: 0, SQLState: null 2020-03-16 17:56:06 ERROR [SqlExceptionHelper.java:144] - wait millis 5488, active 8, maxActive 40, creating 0 2020-03-16 17:56:14 WARN [DruidDataSource.java:1258] - get connection timeout retry : 1 2020-03-16 17:56:27 WARN [DruidDataSource.java:1258] - get connection timeout retry : 1 2020-03-16 17:56:29 ERROR [DruidDataSource.java:2469] - create connection SQLException, url: jdbc:mysql://localhost:55060/mcs?useUnicode=true&characterEncoding=utf-8, errorCode 0, state S1000 java.sql.SQLException: java.lang.OutOfMemoryError: PermGen space at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:965) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:898) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:887) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:861) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:878) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:874) at com.mysql.jdbc.Util.handleNewInstance(Util.java:443) at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:385) at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:323) at com.alibaba.druid.pool.DruidAbstractDataSource.createPhysicalConnection(DruidAbstractDataSource.java:1513) at com.alibaba.druid.pool.DruidAbstractDataSource.createPhysicalConnection(DruidAbstractDataSource.java:1578) at com.alibaba.druid.pool.DruidDataSource$CreateConnectionThread.run(DruidDataSource.java:2466) Caused by: java.lang.OutOfMemoryError: PermGen space 2020-03-16 17:56:37 ERROR [DiskStorageFactory.java:495] - Disk Write of mcs_pic_layer failed: java.lang.OutOfMemoryError: PermGen space 2020-03-16 17:56:37 INFO [BaseHandler.java:42] - 向解码器推送协议{"topic":"controlProtocol/applyBackPicCtrl/00:00:01:A0:43:74/1c79b3b3-6020-4af7-97ec-a1abd5f0cc07","timeStamp":"1584352597266","msgId":"617319811","videoEnable":0,"picList":[{"level":0,"imageEndY":900,"imageEndX":1600,"blockEndY":900,"blockEndX":1600,"blockStartY":180,"imageStartX":320,"picId":16777400,"imageStartY":180,"blockStartX":320}]} 2020-03-16 17:56:37 ERROR [DiskStorageFactory.java:495] - Disk Write of mcs_pic_layer failed: java.lang.OutOfMemoryError: PermGen space 2020-03-16 17:56:49 INFO [MQTTProtocolHandler.java:89] - 接收到返回协议:{"topic":"reControlProtocol/reApplyBackPicCtrl/1c79b3b3-6020-4af7-97ec-a1abd5f0cc07/00:00:01:A0:43:74","result":"success","timeStamp":"1584352597266","msgId":"617319811","msg":"成功"} 2020-03-16 17:56:58 ERROR [DruidDataSource.java:2469] - create connection SQLException, url: jdbc:mysql://localhost:55060/mcs?useUnicode=true&characterEncoding=utf-8, errorCode 0, state S1000 java.sql.SQLException: java.lang.OutOfMemoryError: PermGen space at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:965) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:898) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:887) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:861) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:878) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:874) at com.mysql.jdbc.Util.handleNewInstance(Util.java:443) at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:385) at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:323) at com.alibaba.druid.pool.DruidAbstractDataSource.createPhysicalConnection(DruidAbstractDataSource.java:1513) at com.alibaba.druid.pool.DruidAbstractDataSource.createPhysicalConnection(DruidAbstractDataSource.java:1578) at com.alibaba.druid.pool.DruidDataSource$CreateConnectionThread.run(DruidDataSource.java:2466) Caused by: java.lang.OutOfMemoryError: PermGen space 2020-03-16 17:58:04 INFO [BaseHandler.java:42] - 向解码器推送协议{"topic":"controlProtocol/applyBackPicCtrl/00:00:01:A0:43:74/1c79b3b3-6020-4af7-97ec-a1abd5f0cc07","timeStamp":"1584352684961","msgId":"1580436857","videoEnable":0,"picList":[{"level":0,"imageEndY":900,"imageEndX":1600,"blockEndY":900,"blockEndX":1600,"blockStartY":180,"imageStartX":320,"picId":33554616,"imageStartY":180,"blockStartX":320}]} 2020-03-16 17:58:04 ERROR [DiskStorageFactory.java:495] - Disk Write of mcs_pic_layer failed: java.lang.OutOfMemoryError: PermGen space 2020-03-16 17:58:07 ERROR [DiskStorageFactory.java:495] - Disk Write of mcs_pic_layer failed: java.lang.OutOfMemoryError: PermGen space 2020-03-16 17:58:12 INFO [MQTTProtocolHandler.java:89] - 接收到返回协议:{"topic":"reControlProtocol/reApplyBackPicCtrl/1c79b3b3-6020-4af7-97ec-a1abd5f0cc07/00:00:01:A0:43:74","result":"success","timeStamp":"1584352684961","msgId":"1580436857","msg":"成功"} 2020-03-16 17:58:17 ERROR [DruidDataSource.java:2469] - create connection SQLException, url: jdbc:mysql://localhost:55060/mcs?useUnicode=true&characterEncoding=utf-8, errorCode 0, state S1000 java.sql.SQLException: java.lang.OutOfMemoryError: PermGen space at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:965) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:898) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:887) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:861) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:878) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:874) at com.mysql.jdbc.Util.handleNewInstance(Util.java:443) at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:385) at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:323) at com.alibaba.druid.pool.DruidAbstractDataSource.createPhysicalConnection(DruidAbstractDataSource.java:1513) at com.alibaba.druid.pool.DruidAbstractDataSource.createPhysicalConnection(DruidAbstractDataSource.java:1578) at com.alibaba.druid.pool.DruidDataSource$CreateConnectionThread.run(DruidDataSource.java:2466) Caused by: java.lang.OutOfMemoryError: PermGen space 2020-03-16 17:58:38 ERROR [DruidDataSource.java:2469] - create connection SQLException, url: jdbc:mysql://localhost:55060/mcs?useUnicode=true&characterEncoding=utf-8, errorCode 0, state S1000 java.sql.SQLException: java.lang.OutOfMemoryError: PermGen space at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:965) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:898) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:887) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:861) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:878) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:874) at com.mysql.jdbc.Util.handleNewInstance(Util.java:443) at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:385) at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:323) at com.alibaba.druid.pool.DruidAbstractDataSource.createPhysicalConnection(DruidAbstractDataSource.java:1513) at com.alibaba.druid.pool.DruidAbstractDataSource.createPhysicalConnection(DruidAbstractDataSource.java:1578) at com.alibaba.druid.pool.DruidDataSource$CreateConnectionThread.run(DruidDataSource.java:2466) Caused by: java.lang.OutOfMemoryError: PermGen space 2020-03-16 17:59:06 ERROR [DiskStorageFactory.java:495] - Disk Write of mcs_pic_layer failed: java.lang.OutOfMemoryError: PermGen space 然后这是第二次OOM异常的日志 2020-03-16 17:36:36 INFO [BaseHandler.java:42] - 向解码器推送协议{"topic":"controlProtocol/applyBackPicCtrl/00:00:01:A0:43:74/1c79b3b3-6020-4af7-97ec-a1abd5f0cc07","timeStamp":"1584351396265","msgId":"2054492855","videoEnable":0,"picList":[{"level":0,"imageEndY":900,"imageEndX":1600,"blockEndY":900,"blockEndX":1600,"blockStartY":180,"imageStartX":320,"picId":184,"imageStartY":180,"blockStartX":320}]} 2020-03-16 17:36:36 INFO [MQTTProtocolHandler.java:89] - 接收到返回协议:{"topic":"reControlProtocol/reApplyBackPicCtrl/1c79b3b3-6020-4af7-97ec-a1abd5f0cc07/00:00:01:A0:43:74","result":"success","timeStamp":"1584351396265","msgId":"2054492855","msg":"成功"} 2020-03-16 17:37:36 INFO [BaseHandler.java:42] - 向解码器推送协议{"topic":"controlProtocol/applyBackPicCtrl/00:00:01:A0:43:74/1c79b3b3-6020-4af7-97ec-a1abd5f0cc07","timeStamp":"1584351456281","msgId":"1912161758","videoEnable":0,"picList":[{"level":0,"imageEndY":900,"imageEndX":1600,"blockEndY":900,"blockEndX":1600,"blockStartY":180,"imageStartX":320,"picId":16777400,"imageStartY":180,"blockStartX":320}]} 2020-03-16 17:37:36 INFO [MQTTProtocolHandler.java:89] - 接收到返回协议:{"topic":"reControlProtocol/reApplyBackPicCtrl/1c79b3b3-6020-4af7-97ec-a1abd5f0cc07/00:00:01:A0:43:74","result":"success","timeStamp":"1584351456281","msgId":"1912161758","msg":"成功"} 2020-03-16 17:38:36 INFO [BaseHandler.java:42] - 向解码器推送协议{"topic":"controlProtocol/applyBackPicCtrl/00:00:01:A0:43:74/1c79b3b3-6020-4af7-97ec-a1abd5f0cc07","timeStamp":"1584351516297","msgId":"476243815","videoEnable":0,"picList":[{"level":0,"imageEndY":900,"imageEndX":1600,"blockEndY":900,"blockEndX":1600,"blockStartY":180,"imageStartX":320,"picId":33554616,"imageStartY":180,"blockStartX":320}]} 2020-03-16 17:38:36 INFO [MQTTProtocolHandler.java:89] - 接收到返回协议:{"topic":"reControlProtocol/reApplyBackPicCtrl/1c79b3b3-6020-4af7-97ec-a1abd5f0cc07/00:00:01:A0:43:74","result":"success","timeStamp":"1584351516297","msgId":"476243815","msg":"成功"} 2020-03-16 17:39:36 INFO [BaseHandler.java:42] - 向解码器推送协议{"topic":"controlProtocol/applyBackPicCtrl/00:00:01:A0:43:74/1c79b3b3-6020-4af7-97ec-a1abd5f0cc07","timeStamp":"1584351576307","msgId":"2004523303","videoEnable":0,"picList":[{"level":0,"imageEndY":900,"imageEndX":1600,"blockEndY":900,"blockEndX":1600,"blockStartY":180,"imageStartX":320,"picId":184,"imageStartY":180,"blockStartX":320}]} 2020-03-16 17:39:36 INFO [MQTTProtocolHandler.java:89] - 接收到返回协议:{"topic":"reControlProtocol/reApplyBackPicCtrl/1c79b3b3-6020-4af7-97ec-a1abd5f0cc07/00:00:01:A0:43:74","result":"success","timeStamp":"1584351576307","msgId":"2004523303","msg":"成功"} 2020-03-16 17:39:47 ERROR [DiskStorageFactory.java:495] - Disk Write of mcs_ca92_processor failed: java.lang.OutOfMemoryError: PermGen space 2020-03-16 17:39:47 ERROR [DiskStorageFactory.java:495] - Disk Write of mcs_ca92_processor failed: java.lang.OutOfMemoryError: PermGen space 2020-03-16 17:40:36 INFO [BaseHandler.java:42] - 向解码器推送协议{"topic":"controlProtocol/applyBackPicCtrl/00:00:01:A0:43:74/1c79b3b3-6020-4af7-97ec-a1abd5f0cc07","timeStamp":"1584351636324","msgId":"598577930","videoEnable":0,"picList":[{"level":0,"imageEndY":900,"imageEndX":1600,"blockEndY":900,"blockEndX":1600,"blockStartY":180,"imageStartX":320,"picId":16777400,"imageStartY":180,"blockStartX":320}]} 2020-03-16 17:40:36 ERROR [DiskStorageFactory.java:495] - Disk Write of mcs_pic_layer failed: java.lang.OutOfMemoryError: PermGen space 2020-03-16 17:40:36 ERROR [DiskStorageFactory.java:495] - Disk Write of mcs_pic_layer failed: java.lang.OutOfMemoryError: PermGen space 2020-03-16 17:40:36 INFO [MQTTProtocolHandler.java:89] - 接收到返回协议:{"topic":"reControlProtocol/reApplyBackPicCtrl/1c79b3b3-6020-4af7-97ec-a1abd5f0cc07/00:00:01:A0:43:74","result":"success","timeStamp":"1584351636324","msgId":"598577930","msg":"成功"} 2020-03-16 17:41:36 INFO [BaseHandler.java:42] - 向解码器推送协议{"topic":"controlProtocol/applyBackPicCtrl/00:00:01:A0:43:74/1c79b3b3-6020-4af7-97ec-a1abd5f0cc07","timeStamp":"1584351696340","msgId":"480724569","videoEnable":0,"picList":[{"level":0,"imageEndY":900,"imageEndX":1600,"blockEndY":900,"blockEndX":1600,"blockStartY":180,"imageStartX":320,"picId":16777400,"imageStartY":180,"blockStartX":320}]} 2020-03-16 17:41:36 ERROR [DiskStorageFactory.java:495] - Disk Write of mcs_pic_layer failed: java.lang.OutOfMemoryError: PermGen space 2020-03-16 17:41:36 ERROR [DiskStorageFactory.java:495] - Disk Write of mcs_pic_layer failed: java.lang.OutOfMemoryError: PermGen space 2020-03-16 17:41:36 INFO [MQTTProtocolHandler.java:89] - 接收到返回协议:{"topic":"reControlProtocol/reApplyBackPicCtrl/1c79b3b3-6020-4af7-97ec-a1abd5f0cc07/00:00:01:A0:43:74","result":"success","timeStamp":"1584351696340","msgId":"480724569","msg":"成功"} 2020-03-16 17:42:36 INFO [BaseHandler.java:42] - 向解码器推送协议{"topic":"controlProtocol/applyBackPicCtrl/00:00:01:A0:43:74/1c79b3b3-6020-4af7-97ec-a1abd5f0cc07","timeStamp":"1584351756356","msgId":"2008015594","videoEnable":0,"picList":[{"level":0,"imageEndY":900,"imageEndX":1600,"blockEndY":900,"blockEndX":1600,"blockStartY":180,"imageStartX":320,"picId":33554616,"imageStartY":180,"blockStartX":320}]} 2020-03-16 17:42:36 ERROR [DiskStorageFactory.java:495] - Disk Write of mcs_pic_layer failed: java.lang.OutOfMemoryError: PermGen space 2020-03-16 17:42:36 ERROR [DiskStorageFactory.java:495] - Disk Write of mcs_pic_layer failed: java.lang.OutOfMemoryError: PermGen space 2020-03-16 17:42:36 INFO [MQTTProtocolHandler.java:89] - 接收到返回协议:{"topic":"reControlProtocol/reApplyBackPicCtrl/1c79b3b3-6020-4af7-97ec-a1abd5f0cc07/00:00:01:A0:43:74","result":"success","timeStamp":"1584351756356","msgId":"2008015594","msg":"成功"} 2020-03-16 17:43:36 INFO [BaseHandler.java:42] - 向解码器推送协议{"topic":"controlProtocol/applyBackPicCtrl/00:00:01:A0:43:74/1c79b3b3-6020-4af7-97ec-a1abd5f0cc07","timeStamp":"1584351816372","msgId":"1754653907","videoEnable":0,"picList":[{"level":0,"imageEndY":900,"imageEndX":1600,"blockEndY":900,"blockEndX":1600,"blockStartY":180,"imageStartX":320,"picId":184,"imageStartY":180,"blockStartX":320}]} 2020-03-16 17:43:36 ERROR [DiskStorageFactory.java:495] - Disk Write of mcs_pic_layer failed: java.lang.OutOfMemoryError: PermGen space 2020-03-16 17:43:36 ERROR [DiskStorageFactory.java:495] - Disk Write of mcs_pic_layer failed: java.lang.OutOfMemoryError: PermGen space 2020-03-16 17:43:36 INFO [MQTTProtocolHandler.java:89] - 接收到返回协议:{"topic":"reControlProtocol/reApplyBackPicCtrl/1c79b3b3-6020-4af7-97ec-a1abd5f0cc07/00:00:01:A0:43:74","result":"success","timeStamp":"1584351816372","msgId":"1754653907","msg":"成功"} 2020-03-16 17:44:37 WARN [DruidDataSource.java:1258] - get connection timeout retry : 1 2020-03-16 17:44:38 WARN [DruidDataSource.java:1258] - get connection timeout retry : 1 2020-03-16 17:44:38 WARN [DruidDataSource.java:1258] - get connection timeout retry : 1 2020-03-16 17:44:41 INFO [BaseHandler.java:42] - 向解码器推送协议{"topic":"controlProtocol/applyBackPicCtrl/00:00:01:A0:43:74/1c79b3b3-6020-4af7-97ec-a1abd5f0cc07","timeStamp":"1584351881843","msgId":"327484943","videoEnable":0,"picList":[{"level":0,"imageEndY":900,"imageEndX":1600,"blockEndY":900,"blockEndX":1600,"blockStartY":180,"imageStartX":320,"picId":16777400,"imageStartY":180,"blockStartX":320}]} 2020-03-16 17:44:41 ERROR [DiskStorageFactory.java:495] - Disk Write of mcs_pic_layer failed: java.lang.OutOfMemoryError: PermGen space 2020-03-16 17:44:43 ERROR [DiskStorageFactory.java:495] - Disk Write of mcs_pic_layer failed: java.lang.OutOfMemoryError: PermGen space 2020-03-16 17:44:48 WARN [DruidDataSource.java:1258] - get connection timeout retry : 1 2020-03-16 17:44:48 WARN [DruidDataSource.java:1258] - get connection timeout retry : 1 2020-03-16 17:44:49 INFO [MQTTProtocolHandler.java:89] - 接收到返回协议:{"topic":"reControlProtocol/reApplyBackPicCtrl/1c79b3b3-6020-4af7-97ec-a1abd5f0cc07/00:00:01:A0:43:74","result":"success","timeStamp":"1584351881843","msgId":"327484943","msg":"成功"} 2020-03-16 17:45:02 ERROR [DruidDataSource.java:2469] - create connection SQLException, url: jdbc:mysql://localhost:55060/mcs?useUnicode=true&characterEncoding=utf-8, errorCode 0, state S1000 java.sql.SQLException: java.lang.OutOfMemoryError: PermGen space at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:965) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:898) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:887) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:861) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:878) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:874) at com.mysql.jdbc.Util.handleNewInstance(Util.java:443) at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:385) at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:323) at com.alibaba.druid.pool.DruidAbstractDataSource.createPhysicalConnection(DruidAbstractDataSource.java:1513) at com.alibaba.druid.pool.DruidAbstractDataSource.createPhysicalConnection(DruidAbstractDataSource.java:1578) at com.alibaba.druid.pool.DruidDataSource$CreateConnectionThread.run(DruidDataSource.java:2466) Caused by: java.lang.OutOfMemoryError: PermGen space 2020-03-16 17:45:55 ERROR [DiskStorageFactory.java:495] - Disk Write of mcs_pic_layer failed: java.lang.OutOfMemoryError: PermGen space 2020-03-16 17:45:55 INFO [BaseHandler.java:42] - 向解码器推送协议{"topic":"controlProtocol/applyBackPicCtrl/00:00:01:A0:43:74/1c79b3b3-6020-4af7-97ec-a1abd5f0cc07","timeStamp":"1584351955374","msgId":"690664616","videoEnable":0,"picList":[{"level":0,"imageEndY":900,"imageEndX":1600,"blockEndY":900,"blockEndX":1600,"blockStartY":180,"imageStartX":320,"picId":33554616,"imageStartY":180,"blockStartX":320}]} 2020-03-16 17:45:55 ERROR [DiskStorageFactory.java:495] - Disk Write of mcs_pic_layer failed: java.lang.OutOfMemoryError: PermGen space 2020-03-16 17:46:00 INFO [MQTTProtocolHandler.java:89] - 接收到返回协议:{"topic":"reControlProtocol/reApplyBackPicCtrl/1c79b3b3-6020-4af7-97ec-a1abd5f0cc07/00:00:01:A0:43:74","result":"success","timeStamp":"1584351955374","msgId":"690664616","msg":"成功"} 2020-03-16 17:47:13 INFO [BaseHandler.java:42] - 向解码器推送协议{"topic":"controlProtocol/applyBackPicCtrl/00:00:01:A0:43:74/1c79b3b3-6020-4af7-97ec-a1abd5f0cc07","timeStamp":"1584352033984","msgId":"1701533843","videoEnable":0,"picList":[{"level":0,"imageEndY":900,"imageEndX":1600,"blockEndY":900,"blockEndX":1600,"blockStartY":180,"imageStartX":320,"picId":184,"imageStartY":180,"blockStartX":320}]} 2020-03-16 17:47:13 ERROR [DiskStorageFactory.java:495] - Disk Write of mcs_pic_layer failed: java.lang.OutOfMemoryError: PermGen space 2020-03-16 17:47:14 ERROR [DiskStorageFactory.java:495] - Disk Write of mcs_pic_layer failed: java.lang.OutOfMemoryError: PermGen space 这是我项目的druid配置 <!--druid连接池 --> <beans profile="production"> <context:property-placeholder ignore-unresolvable="true" location="classpath:/jdbc.properties" /> <bean id="dataSource" class="com.alibaba.druid.pool.DruidDataSource" init-method="init" destroy-method="close"> <property name="driverClassName" value="${jdbc.driver}" /> <property name="url" value="${jdbc.url}" /> <property name="username" value="${jdbc.username}" /> <property name="password" value="${jdbc.password}" /> <!-- 配置初始化大小、最小、最大 --> <property name="initialSize" value="1" /> <property name="minIdle" value="1" /> <property name="maxActive" value="40" /> <!-- 配置获取连接等待超时的时间 --> <property name="maxWait" value="5000" /> <!-- 配置间隔多久才进行一次检测,检测需要关闭的空闲连接,单位是毫秒 --> <property name="timeBetweenEvictionRunsMillis" value="60000" /> <!-- 配置一个连接在池中最小生存的时间,单位是毫秒 --> <property name="minEvictableIdleTimeMillis" value="300000" /> <property name="testWhileIdle" value="true" /> <!-- 这里建议配置为TRUE,防止取到的连接不可用 --> <property name="testOnBorrow" value="true" /> <property name="testOnReturn" value="false" /> <!-- 打开PSCache,并且指定每个连接上PSCache的大小 --> <property name="poolPreparedStatements" value="true" /> <property name="maxPoolPreparedStatementPerConnectionSize" value="20" /> <!-- 这里配置提交方式,默认就是TRUE,可以不用配置 --> <property name="defaultAutoCommit" value="true" /> </bean> </beans> 求大佬们帮解答。。。

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tomcat安装到服务后启动访问会报内存溢出

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连接池溢出,如何归还connection

com.alibaba.druid.pool.GetConnectionTimeoutException: wait millis 60000, active 300

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使用连接池时如何解决内存泄漏?

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tomcat 调用连接池机制

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使用连接池时无法初始化,也不报错不知到哪出了问题

package com.server; import java.io.FileInputStream; import java.io.FileNotFoundException; import java.io.IOException; import java.sql.Connection; import java.util.Properties; import org.apache.commons.dbcp.BasicDataSource; /** * 该类用于管理数据库连接 * @author adminitartor * */ public class DBUtil { //数据库连接池 private static BasicDataSource ds; static{ //初始化静态属性 //1加载配置文件 /* * java.util.Properties * 用来读取.properties文件,并解析其中 * 每一行内容,然后以key-value的形式保存 * 在当前实例中。 */ Properties prop = new Properties(); try { prop.load(new FileInputStream("config.properties")); String className = prop.getProperty("classname"); String url = prop.getProperty("url"); String username = prop.getProperty("username"); String password = prop.getProperty("password"); int maxActive = Integer.parseInt(prop.getProperty("maxactive")); int maxWait = Integer.parseInt(prop.getProperty("maxwait")); //初始化连接池 ds=new BasicDataSource(); //将JDBC建立连接所需要的信息设置到连接池中 //Class.forName(...) ds.setDriverClassName(className); //DriverManager.getConnection(...) ds.setUrl(url); ds.setUsername(username); ds.setPassword(password); //设置连接池最大连接数 ds.setMaxActive(maxActive); //设置最大等待时间 ds.setMaxWait(maxWait); } catch (FileNotFoundException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); }catch(Exception e){ e.printStackTrace(); }finally { System.out.println(123); } //2根据配置文件初始化 } /** * 获取数据库连接 * @return */ public static Connection getConnection() throws Exception{ /* * 连接池提供的方法: * Connection getConnection() * 该方法可以返回一个连接池中可用连接。 * 这是一个阻塞方法,当连接池中有空闲连接 * 可以使用时会立刻返回,若当前连接池没有 * 可用连接时,会进入阻塞,阻塞时间由创建 * 连接池时通过setMaxWait设置的时间为准 * 在等待期间若有空闲连接着立即返回,当 * 超过最大等待时间仍没有可用连接时,该方 * 法会抛出超时异常。 */ return ds.getConnection(); } /** * 关闭给定的连接 * @param conn */ public static void closeConnection(Connection conn){ try { conn.setAutoCommit(true); /* * 若该连接是通过连接池获取的,那么调用 * 这个连接的close方法并不是与数据库断开 * 连接了,而仅仅是将该连接还给连接池。 */ conn.close(); } catch (Exception e) { e.printStackTrace(); } } }

最近我公司的网站,服务器时间长了.就会报内存溢出.找不到原因

<p>最近我公司的网站,服务器时间长了,访问量变大.就会报内存溢出.找不到原因. <br />    在网上搜索了很多资料.关于java内存泄露方面的东西.我怀疑是我们java类中用了单例模式惹的祸.但还不敢确定. 我对单例模式,也只懂得一二.希望各位网友.可以讨论讨论.我希望能尽快找到解决方法. <br />    下面是我在网上搜索的一个关于单例模式,有内存泄露的帖子:http://java.csdn.net/page/bf856ae4-ef93-4355-b43d-3735cba92279</p> <p>     大概意思:</p> <pre name="code" class="java">单例模式。不正确使用单例模式是引起内存泄露的一个常见问题,单例对象在被初始化后将在JVM的整个生命周期中存在(以静态变量的方式),如果单例对象持有外部对象的引用,那么这个外部对象将不能被jvm正常回收,导致内存泄露,考虑下面的例子: class A{ public A(){ B.getInstance().setA(this); } .... } //B类采用单例模式 class B{ private A a; private static B instance=new B(); public B(){} public static B getInstance(){ return instance; } public void setA(A a){ this.a=a; } //getter... } 显然B采用singleton模式,他持有一个A对象的引用,而这个A类的对象将不能被回收。想象下如果A是个比较大的对象或者集合类型会发生什么情况。 </pre> <p>  </p> <p>我再贴出我项目中的java代码(提取出来的).供大家分析.</p> <pre name="code" class="java">import java.sql.ResultSet; import java.sql.SQLException; import java.sql.Statement; import org.apache.log4j.Logger; import com.viewbean.Mms; public class MyDBTest { Statement stmt= null; ResultSet res = null; private static final Logger logger = Logger.getLogger(Mms.class); private static final MyDBTest instance = new MyDBTest(); public static MyDBTest getInstance() { return instance; } private MyDBTest() { } /** * * @param con * @param a * @param b * @param c * @param i 调用sql语句的序号. * @return */ public String[][] getOs(java.sql.Connection con,String a,String b ,String c,int i ){ logger.debug("获取某某..."); String[] sql={ // 0. "select a from mysql where a ='"+b+"'", //1. "select a from mysql where b ='"+b+"'", //2. "select a from mysql where c ='"+c+"'" // sql语句都是 用 + 号拼起来的. }; try { stmt = con.createStatement(); res= stmt.executeQuery(sql[i]); //................ //对res进行其他操作.返回一个String[][]二维数组 } catch (SQLException e) { e.printStackTrace(); }finally{ try { if(stmt!=null) stmt.close(); if(res!=null) res.close(); //con 连接对象.在jsp中被关闭. } catch (SQLException e) { e.printStackTrace(); } sql=null; } return null;//实际返回二维数组.现在模式返回null; } public boolean deleteGif(java.sql.Connection conn,String aa) { logger.debug("删除某某..."); return false; } public void insertmms(java.sql.Connection con,String linkid,String id){ logger.debug("添加某某..."); } } </pre> <p> </p> <p> </p> <p>    由于是一个网站项目,没有很复杂的框架.应用了简单的jsp+javabean模式开发.</p> <p>   所以都是在jsp或者servlet中创建连接对象.然后调用这些java类.并且这些类都应用了单利模式.</p> <p>其他的jsp直接调用getInstance()方法.然后调用其中的方法.执行sql操作.并且连接对象是在jsp中try{}catch{}finally{}</p> <p> finally{}里中关闭里.所有jsp中的对象和String,String[][]都设置为null.</p> <p>   </p> <p>现在我的疑问就是:1.向我这种代码.javabean设置为单例模式,会不会有内存泄露的结果.</p> <p>                          2.我那是用了logger4j的对象,始终没有清空他.他应不应该进行logger =null 操作.</p> <p>                          3.还有拼sql 语句.有没有跟好的方法.</p> <p>                          4.在finally{} 将对象置为null  ,是不是真的内存回收了呢?</p> <p>   </p> <p> </p> <p>    </p><br /><strong>问题补充:</strong><br />我们项目应用了 数据库连接池.如果数据库连接池没有链接到,就用直连的. <br /> <br /> <br />我们获取Connection大多数在jsp中/比如: <br />&lt;%  <br />// 查询某用户的未读消息几条 <br />   Connection conn  =  null; <br />   String[][]  strNewCount=null; <br />   try{ <br />   conn  =  DBAccess.getPooledConnection(); <br /> strNewCount=MessageManageDao.getInstance().pageQueryMessage(conn,userId,-1,-1,0,2); <br /> if(strNewCount!=null&amp;&amp;strNewCount.length&gt;0){ <br />    newCounts= Integer.parseInt(strNewCount[0][0]); <br /> } <br /> }catch(Exception e){ <br /> e.printStackTrace();} <br />finally{ <br />DBAccess.closeConnection(conn); <br />} <br /> <br />%&gt; <br /> <br /> <br />在servlet里面的连接.都是写在doGet() 或 doPost() 方法里面的. <br /> <br /> <br />希望大家继续关注.... <br />      <br /><strong>问题补充:</strong><br />问题再次补充并进行我的分析: <br /> <br /> <br />回答,墓里活人: <br />    我那个页面不是专门用来获得连接.也没有其他页面包含他,我说的是,我用很多 jsp页面,这些页面如果要获取数据,进行操作.都是直接&lt;% %&gt; 在这个里面获取连接,并调用方法.获得String[][]返回或无返回值. <br />    获得的连接.在页面末尾的finally{} 块中关闭啦. <br />     <br />    单例.那个B类的构造方法,没有写那个private,我是copy别人的帖子中 <br /> <br />的.我猜是手误. <br /> <br />我的疑问: <br />  1. 如果我一个jsp页面,要调用很多dao类里的方法,为什么不把Connection 在页面获取呢,可以直接传到Dao类.这样不比在Dao类中的每个方法里面重新获取连接不更好吗? <br />   <br />   2.如果按照最上面的那个帖子的说法,采用单例模式的类里面如果有其他类的引用或对象,这些对象是不是永远不会销毁呢?这是内存泄露吗? <br /> <br /> <br /> <br /><br /><strong>问题补充:</strong><br />错别字更正:"我用很多 jsp页面"  ---&gt;&gt;&gt;  "我有很多jsp页面"

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druid 连接池溢出 getconnectiontimeoutexception

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org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:255) at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:94) at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172) at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:91) at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172) at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:204) at com.sun.proxy.$Proxy46.login(Unknown Source) at cn.bainaonline.bnerp.system.controller.UserController.login(UserController.java:100) at sun.reflect.GeneratedMethodAccessor332.invoke(Unknown Source) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) at java.lang.reflect.Method.invoke(Method.java:597) 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