Примечание: я знаю оэтот нить но она довольно старая и более того, решение у меня не сработало.

Я использую App Engine вместе с Cloud SQL, и я хотел бы разделить пул открытых соединений между всеми текущими пользователями приложения. Я пробовал несколько реализаций пула соединений, и все они отлично работают с локальным сервером разработки, однако при развертывании в облаке они терпят неудачу. Я полагаю, что причиной является ограниченная среда «песочницы» App Engine. Кто-нибудь знает о пуле соединений JDBC, работающем на App Engine?

Apache Commons DBCP

...
Caused by: java.lang.NoClassDefFoundError: Could not initialize class org.apache.commons.dbcp2.PoolableConnection
at com.google.appengine.runtime.Request.process-a49d46300800d0ca(Request.java)
at org.apache.commons.dbcp2.PoolableConnectionFactory.makeObject(PoolableConnectionFactory.java:254)
at org.apache.commons.dbcp2.BasicDataSource.validateConnectionFactory(BasicDataSource.java:2162)
at org.apache.commons.dbcp2.BasicDataSource.createPoolableConnectionFactory(BasicDataSource.java:2148)
at org.apache.commons.dbcp2.BasicDataSource.createDataSource(BasicDataSource.java:1903)
at org.apache.commons.dbcp2.BasicDataSource$PaGetConnection.run(BasicDataSource.java:2267)
at org.apache.commons.dbcp2.BasicDataSource$PaGetConnection.run(BasicDataSource.java:2263)
at java.security.AccessController.doPrivileged(AccessController.java:63)
at org.apache.commons.dbcp2.BasicDataSource.getConnection(BasicDataSource.java:1404)
...

Tomcat JDBC Connection Pool

...
Caused by: java.lang.SecurityException: Unable to get members for class org.apache.tomcat.jdbc.pool.DataSource

...

Caused by: java.lang.reflect.InvocationTargetException
at sun.reflect.GeneratedMethodAccessor9.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
... 45 more
Caused by: java.lang.NoClassDefFoundError: javax/management/MalformedObjectNameException
at java.lang.Class.getDeclaredMethods0(Native Method)
at java.lang.Class.privateGetDeclaredMethods(Class.java:2517)
... 45 more
Caused by: java.lang.ClassNotFoundException: javax.management.MalformedObjectNameException
... 45 more

HikariCP

...
java.security.AccessControlException: access denied ("java.lang.RuntimePermission" "modifyThreadGroup")
at java.security.AccessControlContext.checkPermission(AccessControlContext.java:375)
at java.security.AccessController.checkPermission(AccessController.java:565)
at java.lang.SecurityManager.checkPermission(SecurityManager.java:549)
at java.lang.ThreadGroup.checkAccess(ThreadGroup.java:315)
at java.lang.Thread.init(Thread.java:378)
at java.lang.Thread.<init>(Thread.java:527)
at com.zaxxer.hikari.util.DefaultThreadFactory.newThread(DefaultThreadFactory.java:32)
at java.util.concurrent.ThreadPoolExecutor$Worker.<init>(ThreadPoolExecutor.java:591)
at java.util.concurrent.ThreadPoolExecutor.addWorker(ThreadPoolExecutor.java:922)
at java.util.concurrent.ThreadPoolExecutor.ensurePrestart(ThreadPoolExecutor.java:1591)
at java.util.concurrent.ScheduledThreadPoolExecutor.delayedExecute(ScheduledThreadPoolExecutor.java:305)
at java.util.concurrent.ScheduledThreadPoolExecutor.scheduleAtFixedRate(ScheduledThreadPoolExecutor.java:542)
at com.zaxxer.hikari.pool.HikariPool.<init>(HikariPool.java:161)
at com.zaxxer.hikari.pool.HikariPool.<init>(HikariPool.java:114)
at com.zaxxer.hikari.HikariDataSource.getConnection(HikariDataSource.java:102)
...

Vibur DBCP

...
Caused by: java.security.AccessControlException: access denied ("java.lang.RuntimePermission" "modifyThreadGroup")
at java.security.AccessControlContext.checkPermission(AccessControlContext.java:375)
at java.security.AccessController.checkPermission(AccessController.java:565)
at java.lang.SecurityManager.checkPermission(SecurityManager.java:549)
at java.lang.ThreadGroup.checkAccess(ThreadGroup.java:315)
at java.lang.Thread.init(Thread.java:378)
at java.lang.Thread.<init>(Thread.java:448)
at org.vibur.objectpool.reducer.SamplingPoolReducer.<init>(SamplingPoolReducer.java:78)
at org.vibur.dbcp.pool.PoolOperations$PoolReducer.<init>(PoolOperations.java:88)
at org.vibur.dbcp.pool.PoolOperations$PoolReducer.<init>(PoolOperations.java:86)
at org.vibur.dbcp.pool.PoolOperations.<init>(PoolOperations.java:79)
at org.vibur.dbcp.ViburDBCPDataSource.start(ViburDBCPDataSource.java:197)
....

c3p0

...
Caused by: java.security.AccessControlException: access denied ("java.lang.RuntimePermission" "modifyThreadGroup")
at java.security.AccessControlContext.checkPermission(AccessControlContext.java:375)
at java.security.AccessController.checkPermission(AccessController.java:565)
at java.lang.SecurityManager.checkPermission(SecurityManager.java:549)
at java.lang.ThreadGroup.checkAccess(ThreadGroup.java:315)
at java.lang.Thread.init(Thread.java:378)
at java.lang.Thread.<init>(Thread.java:487)
...