Tomcat启动项目出现使用远程数据库报错java.net.SocketException: java.security.AccessControlException: access denied

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最新推荐文章于 2025-02-27 14:03:03 发布

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文章标签： java 数据库 c3p0 Tomcat部署

本文链接：https://blog.youkuaiyun.com/s383253107/article/details/82783196

本文详细记录了一次使用c3p0连接池在Tomcat环境下遇到的死锁问题及其解决方案。通过调整java.security.policy和catalina.policy文件中的SocketPermission设置，最终成功解决了数据库连接失败的问题。

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com.mchange.v2.c3p0.impl.AbstractPoolBackedDataSource getPoolManager
INFO: Initializing c3p0 pool... com.mchange.v2.c3p0.ComboPooledDataSource [ acquireIncrement -> 3, acquireRetryAttempts -> 30, acquireRetryDelay -> 1000, autoCommitOnClose -> false, automaticTestTable -> null, breakAfterAcquireFailure -> false, checkoutTimeout -> 0, connectionCustomizerClassName -> null, connectionTesterClassName -> com.mchange.v2.c3p0.impl.DefaultConnectionTester, dataSourceName -> z8kflt9x1ut514d1dyi1jm|49499ee2, debugUnreturnedConnectionStackTraces -> false, description -> null, driverClass -> com.mysql.jdbc.Driver, factoryClassLocation -> null, forceIgnoreUnresolvedTransactions -> false, identityToken -> z8kflt9x1ut514d1dyi1jm|49499ee2, idleConnectionTestPeriod -> 0, initialPoolSize -> 5, jdbcUrl -> jdbc:mysql://192.168.8.128:3306/hotel?useUnicode=true&characterEncoding=utf8, maxAdministrativeTaskTime -> 0, maxConnectionAge -> 0, maxIdleTime -> 0, maxIdleTimeExcessConnections -> 0, maxPoolSize -> 10, maxStatements -> 0, maxStatementsPerConnection -> 0, minPoolSize -> 3, numHelperThreads -> 3, numThreadsAwaitingCheckoutDefaultUser -> 0, preferredTestQuery -> null, properties -> {user=******}, propertyCycle -> 0, testConnectionOnCheckin -> false, testConnectionOnCheckout -> false, unreturnedConnectionTimeout -> 0, usesTraditionalReflectiveProxies -> false ]
九月 19, 2018 3:44:15 下午 com.mchange.v2.async.ThreadPoolAsynchronousRunner$DeadlockDetector run
WARNING: com.mchange.v2.async.ThreadPoolAsynchronousRunner$DeadlockDetector@7a54c7a6 -- APPARENT DEADLOCK!!! Creating emergency threads for unassigned pending tasks!
九月 19, 2018 3:44:15 下午 com.mchange.v2.async.ThreadPoolAsynchronousRunner$DeadlockDetector run
WARNING: com.mchange.v2.async.ThreadPoolAsynchronousRunner$DeadlockDetector@7a54c7a6 -- APPARENT DEADLOCK!!! Complete Status:
   Managed Threads: 3
   Active Threads: 3
   Active Tasks:
       com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask@4d1d82a (com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread-#2)
       com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask@110e1e7a (com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread-#0)
       com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask@5581d3e8 (com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread-#1)
   Pending Tasks:
       com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask@610c5cb7
       com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask@6b16c834
Pool thread stack traces:
   [Stack traces of deadlocked task threads not available.]
九月 19, 2018 3:44:25 下午 com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask run
WARNING: com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask@4d1d82a -- Acquisition Attempt Failed!!! Clearing pending acquires. While trying to acquire a needed new resource, we failed to succeed more than the maximum number of allowed acquisition attempts (30). Last acquisition attempt exception:
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.GeneratedConstructorAccessor16.newInstance(Unknown Source)
   at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
   at java.lang.reflect.Constructor.newInstance(Constructor.java:423)
   at com.mysql.jdbc.Util.handleNewInstance(Util.java:409)
   at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1122)
   at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2260)
   at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:787)
   at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:49)
   at sun.reflect.GeneratedConstructorAccessor21.newInstance(Unknown Source)
   at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
   at java.lang.reflect.Constructor.newInstance(Constructor.java:423)
   at com.mysql.jdbc.Util.handleNewInstance(Util.java:409)
   at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:357)
   at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:285)
   at com.mchange.v2.c3p0.DriverManagerDataSource.getConnection(DriverManagerDataSource.java:134)
   at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:182)
   at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:171)
   at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool$1PooledConnectionResourcePoolManager.acquireResource(C3P0PooledConnectionPool.java:137)
   at com.mchange.v2.resourcepool.BasicResourcePool.doAcquire(BasicResourcePool.java:1014)
   at com.mchange.v2.resourcepool.BasicResourcePool.access$800(BasicResourcePool.java:32)
   at com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask.run(BasicResourcePool.java:1810)
   at com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:547)
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.GeneratedConstructorAccessor16.newInstance(Unknown Source)
   at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
   at java.lang.reflect.Constructor.newInstance(Constructor.java:423)
   at com.mysql.jdbc.Util.handleNewInstance(Util.java:409)
   at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1122)
   at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:344)
   at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2181)
   ... 16 more
Caused by: java.net.SocketException: java.security.AccessControlException: access denied ("java.net.SocketPermission" "192.168.8.128:3306" "connect,resolve")
   at com.mysql.jdbc.StandardSocketFactory.unwrapExceptionToProperClassAndThrowIt(StandardSocketFactory.java:407)
   at com.mysql.jdbc.StandardSocketFactory.connect(StandardSocketFactory.java:268)
   at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:293)
   ... 17 more

环境：eclipse2017，使用c3p0连接池连接数据库，数据库在虚拟机的Ubuntu环境下， IE && eclipse在Windows操作。

使用java代码单元测试可以正常操作远程数据库。但是将项目部署到Tomcat8.5（eclipse自带的）上，访问数据库始终报上面的错误。纠结了几天。修改过JAVA_HOME\jre\lib\security\java.policy，有添加

permission java.net.SocketPermission "192.168.8.128:3306","accept";
permission java.net.SocketPermission "192.168.8.128:3306","listen";
permission java.net.SocketPermission "192.168.8.128:3306","resolve";
permission java.net.SocketPermission "192.168.8.128:3306","connect";

始终不行。最后实在没办法，到处找帖子。终于自己发现在java workspace下面（Tomcat会生成一个servers文件夹放在该目录下。）Servers\MyEclipse Tomcat v8.5-config\catalina.policy 这个文件里面进行配置权限--将上面的4行代码贴在grant { } 里面。