Backendless encountered an error while handling the request. An internal trouble ticket with ID bl-server:7D8D9B7F-1983-40E4-AF1D-343FA09202CE has been created and we will be investigating the issue.
java.sql.SQLException: Could not retrieve connection info from pool
java.lang.RuntimeException: java.sql.SQLException: Could not retrieve connection info from pool
	at com.backendless.db.connection.pool.BaseConnectionPool.getConnection(BaseConnectionPool.java:38)
	at com.backendless.db.connection.pool.DbCpConnectionPool.getConnection(DbCpConnectionPool.java:40)
	at com.backendless.db.connection.pool.ShardedConnectionPoolManager.buildConnection(ShardedConnectionPoolManager.java:107)
	at com.backendless.db.connection.pool.ShardedConnectionPoolManager.getConnection(ShardedConnectionPoolManager.java:73)
	at com.backendless.db.connection.pool.ShardedConnectionPoolManager.getConnection(ShardedConnectionPoolManager.java:67)
	at com.backendless.util.db.DbcpConnectionProviderImpl.getConnection(DbcpConnectionProviderImpl.java:68)
	at com.backendless.util.db.DbcpConnectionProviderImpl.getConnection(DbcpConnectionProviderImpl.java:57)
	at org.hibernate.internal.NonContextualJdbcConnectionAccess.obtainConnection(NonContextualJdbcConnectionAccess.java:38)
	at org.hibernate.resource.jdbc.internal.LogicalConnectionManagedImpl.acquireConnectionIfNeeded(LogicalConnectionManagedImpl.java:108)
	at org.hibernate.resource.jdbc.internal.LogicalConnectionManagedImpl.getPhysicalConnection(LogicalConnectionManagedImpl.java:138)
	at org.hibernate.engine.jdbc.internal.StatementPreparerImpl.connection(StatementPreparerImpl.java:50)
	at org.hibernate.engine.jdbc.internal.StatementPreparerImpl$5.doPrepare(StatementPreparerImpl.java:149)
	at org.hibernate.engine.jdbc.internal.StatementPreparerImpl$StatementPreparationTemplate.prepareStatement(StatementPreparerImpl.java:176)
	at org.hibernate.engine.jdbc.internal.StatementPreparerImpl.prepareQueryStatement(StatementPreparerImpl.java:151)
	at org.hibernate.loader.Loader.prepareQueryStatement(Loader.java:2122)
	at org.hibernate.loader.Loader.executeQueryStatement(Loader.java:2059)
	at org.hibernate.loader.Loader.executeQueryStatement(Loader.java:2037)
	at org.hibernate.loader.Loader.doQuery(Loader.java:956)
	at org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:357)
	at org.hibernate.loader.Loader.doList(Loader.java:2868)
	at org.hibernate.loader.Loader.listUsingQueryCache(Loader.java:2712)
	at org.hibernate.loader.Loader.list(Loader.java:2674)
	at org.hibernate.loader.hql.QueryLoader.list(QueryLoader.java:540)
	at org.hibernate.hql.internal.ast.QueryTranslatorImpl.list(QueryTranslatorImpl.java:400)
	at org.hibernate.engine.query.spi.HQLQueryPlan.performList(HQLQueryPlan.java:219)
	at org.hibernate.internal.SessionImpl.list(SessionImpl.java:1459)
	at org.hibernate.query.internal.AbstractProducedQuery.doList(AbstractProducedQuery.java:1649)
	at org.hibernate.query.internal.AbstractProducedQuery.list(AbstractProducedQuery.java:1617)
	at org.hibernate.query.Query.getResultList(Query.java:165)
	at com.backendless.datamodel.main.dao.ApplicationDao.lambda$findByDeveloperId$9(ApplicationDao.java:148)
	at com.backendless.datamodel.main.dao.MainJpaContext.executeSync(MainJpaContext.java:69)
	at com.backendless.datamodel.main.dao.MainJpaContext.execute(MainJpaContext.java:43)
	at com.backendless.datamodel.main.dao.ApplicationDao.findByDeveloperId(ApplicationDao.java:142)
	at com.backendless.management.myapplication.MyApplicationService.lambda$getApplicationsForCurrentZone$3(MyApplicationService.java:232)
	at com.backendless.datamodel.main.dao.MainJpaContext.executeSync(MainJpaContext.java:69)
	at com.backendless.datamodel.main.dao.MainJpaContext.execute(MainJpaContext.java:43)
	at com.backendless.management.myapplication.MyApplicationService.getApplicationsForCurrentZone(MyApplicationService.java:230)
	at controllers.console.MyApplication.lambda$getApplications$0(MyApplication.java:103)
	at com.backendless.datamodel.main.dao.MainJpaContext.executeSync(MainJpaContext.java:69)
	at com.backendless.datamodel.main.dao.MainJpaContext.lambda$execute$0(MainJpaContext.java:37)
	at java.base/java.util.concurrent.CompletableFuture$AsyncSupply.run(CompletableFuture.java:1768)
	at com.backendless.async.BackendlessExecutorService.lambda$execute$2(BackendlessExecutorService.java:160)
	at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1136)
	at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:635)
	at java.base/java.lang.Thread.run(Thread.java:840)
Caused by: java.sql.SQLException: Could not retrieve connection info from pool
	at org.apache.commons.dbcp2.datasources.SharedPoolDataSource.getPooledConnectionAndInfo(SharedPoolDataSource.java:130)
	at org.apache.commons.dbcp2.datasources.InstanceKeyDataSource.getConnection(InstanceKeyDataSource.java:206)
	at org.apache.commons.dbcp2.datasources.InstanceKeyDataSource.getConnection(InstanceKeyDataSource.java:183)
	at com.backendless.db.connection.pool.BaseConnectionPool.getConnection(BaseConnectionPool.java:34)
	... 44 more
Caused by: com.mysql.cj.jdbc.exceptions.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 com.mysql.cj.jdbc.exceptions.SQLError.createCommunicationsException(SQLError.java:174)
	at com.mysql.cj.jdbc.exceptions.SQLExceptionsMapping.translateException(SQLExceptionsMapping.java:64)
	at com.mysql.cj.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:815)
	at com.mysql.cj.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:438)
	at com.mysql.cj.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:241)
	at com.mysql.cj.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:189)
	at java.sql/java.sql.DriverManager.getConnection(DriverManager.java:681)
	at java.sql/java.sql.DriverManager.getConnection(DriverManager.java:190)
	at org.apache.commons.dbcp2.cpdsadapter.DriverAdapterCPDS.getPooledConnection(DriverAdapterCPDS.java:393)
	at org.apache.commons.dbcp2.cpdsadapter.DriverAdapterCPDS.getPooledConnection(DriverAdapterCPDS.java:373)
	at org.apache.commons.dbcp2.datasources.KeyedCPDSConnectionFactory.makeObject(KeyedCPDSConnectionFactory.java:241)
	at org.apache.commons.dbcp2.datasources.KeyedCPDSConnectionFactory.makeObject(KeyedCPDSConnectionFactory.java:46)
	at org.apache.commons.pool2.impl.GenericKeyedObjectPool.create(GenericKeyedObjectPool.java:796)
	at org.apache.commons.pool2.impl.GenericKeyedObjectPool.borrowObject(GenericKeyedObjectPool.java:444)
	at org.apache.commons.pool2.impl.GenericKeyedObjectPool.borrowObject(GenericKeyedObjectPool.java:355)
	at org.apache.commons.dbcp2.datasources.SharedPoolDataSource.getPooledConnectionAndInfo(SharedPoolDataSource.java:128)
	... 47 more
Caused by: com.mysql.cj.exceptions.CJCommunicationsException: 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 jdk.internal.reflect.GeneratedConstructorAccessor339.newInstance(Unknown Source)
	at java.base/jdk.internal.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
	at java.base/java.lang.reflect.Constructor.newInstanceWithCaller(Constructor.java:499)
	at java.base/java.lang.reflect.Constructor.newInstance(Constructor.java:480)
	at com.mysql.cj.exceptions.ExceptionFactory.createException(ExceptionFactory.java:61)
	at com.mysql.cj.exceptions.ExceptionFactory.createException(ExceptionFactory.java:104)
	at com.mysql.cj.exceptions.ExceptionFactory.createException(ExceptionFactory.java:149)
	at com.mysql.cj.exceptions.ExceptionFactory.createCommunicationsException(ExceptionFactory.java:165)
	at com.mysql.cj.protocol.a.NativeSocketConnection.connect(NativeSocketConnection.java:88)
	at com.mysql.cj.NativeSession.connect(NativeSession.java:120)
	at com.mysql.cj.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:935)
	at com.mysql.cj.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:805)
	... 60 more
Caused by: java.net.ConnectException: Connection refused
	at java.base/sun.nio.ch.Net.connect0(Native Method)
	at java.base/sun.nio.ch.Net.connect(Net.java:579)
	at java.base/sun.nio.ch.Net.connect(Net.java:568)
	at java.base/sun.nio.ch.NioSocketImpl.connect(NioSocketImpl.java:593)
	at java.base/java.net.SocksSocketImpl.connect(SocksSocketImpl.java:327)
	at java.base/java.net.Socket.connect(Socket.java:633)
	at com.mysql.cj.protocol.StandardSocketFactory.connect(StandardSocketFactory.java:153)
	at com.mysql.cj.protocol.a.NativeSocketConnection.connect(NativeSocketConnection.java:62)
	... 63 more