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Statement.setQueryTimeout doesn't work on Oracle 18c jdbc driver

We have a J2EE application on a payara 5.2020 server that executes a long running query (PL/SQL that executes for a couple of hours).
To avoid a timeout exception, we use this sentence at StatementLevel:
statement.setQueryTimeout(0);
This works using Oracle jdbc drivers version 12c, but when we have migrated to Oracle 18c, and we changed the driver to the version 18c, the query execution stops after 15 minutes with this exception. The code works with Oracle 12 and Oracle 18 is the change in the driver's jar what brings up the problem.
The problem has been reproduced in Linux and Windows machines:
2021-06-14T07:50:01.762+0200|SEVERE: java.sql.SQLRecoverableException: Error de E/S: Socket read interrupted
at oracle.jdbc.driver.T4CCallableStatement.executeForRows(T4CCallableStatement.java:946)
at oracle.jdbc.driver.OracleStatement.doExecuteWithTimeout(OracleStatement.java:1136)
at oracle.jdbc.driver.OraclePreparedStatement.executeInternal(OraclePreparedStatement.java:3640)
at oracle.jdbc.driver.T4CCallableStatement.executeInternal(T4CCallableStatement.java:1318)
at oracle.jdbc.driver.OraclePreparedStatement.execute(OraclePreparedStatement.java:3752)
at oracle.jdbc.driver.OracleCallableStatement.execute(OracleCallableStatement.java:4242)
at oracle.jdbc.driver.OraclePreparedStatementWrapper.execute(OraclePreparedStatementWrapper.java:1079)
at com.sun.gjc.spi.base.PreparedStatementWrapper.execute(PreparedStatementWrapper.java:532)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:566)
at com.sun.gjc.spi.jdbc40.ProfiledConnectionWrapper40$1.invoke(ProfiledConnectionWrapper40.java:437)
at com.sun.proxy.$Proxy324.execute(Unknown Source)
at org.apache.jsp.index_jsp.callPL(index_jsp.java:49)
at org.apache.jsp.index_jsp._jspService(index_jsp.java:108)
at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:111)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:750)
at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:411)
at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:473)
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:377)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:750)
at org.apache.catalina.core.StandardWrapper.service(StandardWrapper.java:1636)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:259)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:161)
at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:757)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:577)
at com.sun.enterprise.web.WebPipeline.invoke(WebPipeline.java:99)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:158)
at org.apache.catalina.connector.CoyoteAdapter.doService(CoyoteAdapter.java:371)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:238)
at com.sun.enterprise.v3.services.impl.ContainerMapper$HttpHandlerCallable.call(ContainerMapper.java:520)
at com.sun.enterprise.v3.services.impl.ContainerMapper.service(ContainerMapper.java:217)
at org.glassfish.grizzly.http.server.HttpHandler.runService(HttpHandler.java:182)
at org.glassfish.grizzly.http.server.HttpHandler.doHandle(HttpHandler.java:156)
at org.glassfish.grizzly.http.server.HttpServerFilter.handleRead(HttpServerFilter.java:218)
at org.glassfish.grizzly.filterchain.ExecutorResolver$9.execute(ExecutorResolver.java:95)
at org.glassfish.grizzly.filterchain.DefaultFilterChain.executeFilter(DefaultFilterChain.java:260)
at org.glassfish.grizzly.filterchain.DefaultFilterChain.executeChainPart(DefaultFilterChain.java:177)
at org.glassfish.grizzly.filterchain.DefaultFilterChain.execute(DefaultFilterChain.java:109)
at org.glassfish.grizzly.filterchain.DefaultFilterChain.process(DefaultFilterChain.java:88)
at org.glassfish.grizzly.ProcessorExecutor.execute(ProcessorExecutor.java:53)
at org.glassfish.grizzly.nio.transport.TCPNIOTransport.fireIOEvent(TCPNIOTransport.java:524)
at org.glassfish.grizzly.strategies.AbstractIOStrategy.fireIOEvent(AbstractIOStrategy.java:89)
at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy.run0(WorkerThreadIOStrategy.java:94)
at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy.access$100(WorkerThreadIOStrategy.java:33)
at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy$WorkerThreadRunnable.run(WorkerThreadIOStrategy.java:114)
at org.glassfish.grizzly.threadpool.AbstractThreadPool$Worker.doWork(AbstractThreadPool.java:569)
at org.glassfish.grizzly.threadpool.AbstractThreadPool$Worker.run(AbstractThreadPool.java:549)
at java.base/java.lang.Thread.run(Thread.java:834)
Caused by: java.io.InterruptedIOException: Socket read interrupted
at oracle.net.nt.TimeoutSocketChannel.handleInterrupt(TimeoutSocketChannel.java:262)
at oracle.net.nt.TimeoutSocketChannel.read(TimeoutSocketChannel.java:184)
at oracle.net.ns.NSProtocolNIO.doSocketRead(NSProtocolNIO.java:544)
at oracle.net.ns.NIOPacket.readHeader(NIOPacket.java:234)
at oracle.net.ns.NIOPacket.readPacketFromSocketChannel(NIOPacket.java:174)
at oracle.net.ns.NIOPacket.readFromSocketChannel(NIOPacket.java:122)
at oracle.net.ns.NIOPacket.readFromSocketChannel(NIOPacket.java:100)
at oracle.net.ns.NIONSDataChannel.readDataFromSocketChannel(NIONSDataChannel.java:86)
at oracle.jdbc.driver.T4CMAREngineNIO.prepareForUnmarshall(T4CMAREngineNIO.java:762)
at oracle.jdbc.driver.T4CMAREngineNIO.unmarshalUB1(T4CMAREngineNIO.java:427)
at oracle.jdbc.driver.T4CTTIfun.receive(T4CTTIfun.java:394)
at oracle.jdbc.driver.T4CTTIfun.doRPC(T4CTTIfun.java:255)
at oracle.jdbc.driver.T4C8Oall.doOALL(T4C8Oall.java:610)
at oracle.jdbc.driver.T4CCallableStatement.doOall8(T4CCallableStatement.java:249)
at oracle.jdbc.driver.T4CCallableStatement.doOall8(T4CCallableStatement.java:82)
at oracle.jdbc.driver.T4CCallableStatement.executeForRows(T4CCallableStatement.java:924)
It seems the transport layer has been migrated to java.nio and the method setQueryTimeout is no longer
Things We've tried:
Setting the default Statement timeout to -1 in the JDBC Connection Pool Advanced Attributes screen in payara console.
Trying to set the time directly in the connection with conn.setNetworkTimeout(Executors.newFixedThreadPool(1), 0) didn't make any effect.
In different sources we have found that these properties below should affect the network timeout evaluation. We set them as JVM properties for payara startup (-Doracle.net.CONNECT_TIMEOUT=xxx) and as JDBC Connection Pool Properties, both cases with values 0 and -1. Didn't work in any case.
oracle.net.CONNECT_TIMEOUT
oracle.net.READ_TIMEOUT
oracle.jdbc.ReadTimeout
Sources:
Oracle 18c Net services best practices
Oracle 18c java jdbc reference. E.1.5 Using JDBC with Firewalls
4.- As we are accessing the DataSource through payara DataSource pool, we cannot cast the com.sun.gjc.spi.jdbc40.DataSource40 (class provided by payara) to an OracleDataSource, but we created the DataSorce programatically to set the connection properties as shown here and setting the properties seen in the image above but it doesn't work:
public static Properties oracleProperties() {
// Already tried -1 and 0
Properties properties = new Properties();
properties.put("Oracle.net.CONNECT_TIMEOUT", 0);
properties.put("Oracle.net.READ_TIMEOUT", 0);
properties.put("Oracle.jdbc.ReadTimeout", 0);
return properties;
}
public static OracleDataSource createDataSource() throws Exception {
OracleDataSource ods = new OracleDataSource();
ods.setURL("jdbc:oracle:thin:#itauc4602x:1521/BDExp");
ods.setUser("enevac");
ods.setPassword("enevac");
ods.setDataSourceName("OracleXADataSource");
ods.setLoginTimeout(0);
// default connection properties to avoid timeoutException
ods.setConnectionProperties(oracleProperties());
return ods;
}
Has anyone faced this problem, any idea on how to avoid the timeOut restriction?
Why 15 minutes?, according to the reference, the default value for oracle.net.ReadTimeout is 10 minutes.
Update:
To explain in more detail why I think the problem is in the driver and why I discard other possible origins of the exception, I assume the timeout can be raised from three sources:
Network timeout: I discard it cause I'm testing a payara server in my local machine against the development database, with no firewall in between.
Database server: the DBA has checked the Oracle net services configuration and there's no limit set that explains the 15 minutes cut. Besides, in these case, an SQLException would be expected with some kind of ORA-xxx error code.
JDBC: this can be set at connection level, statement level and transaction level. As I said at the beginning, the code works with oracle 12c drivers against Oracle 12 and Oracle 18 servers, it was the change of the driver's jar what make the code stop working.

Finally the problem was fixed configuring in the payara pool the "connectionProperties" custom property of the OracleDataSource. As #ibre5041 pointed, setting the property oracle.jdbc.javaNetNio=false changes the transport layer used by the driver and it starts working as the oracle 12c previous version.
According to Oracle reference, the OracleDataSource implementors can receive the connection properties as a java.util.Properties object.
Table 8-2 Oracle Extended Data Source Properties
Name: connectionProperties
Type: java.util.Properties
Description: Specifies the connection properties.
To set a multivalued property to the jdbc pool in the Payara Admin Console, you have to set the properties as (prop1=value1,prop2=value2), (Thank you again Ondro Mihályi). So in our case we set:
connectionProperties = (oracle.jdbc.ReadTimeout=0, oracle.jdbc.javaNetNio=false)
As a summary of what works and doesn't using Oracle 18c jdbc driver (every step tested separately)::
Setting timeout at statement level doesn't work:
statement.setQueryTimeout(0)
Setting timeout at connection level, with -1 or 0, doesn't work:
conn.setNetworkTimeout(Executors.newFixedThreadPool(1), timeout in ms)
Setting timeout properties programmatically in the java.util.connection using the OracleDataSource makes it work as indicated in the question.
Setting timeout properties as JVM properties makes it work if the limit is below 15min, but if you set a value > 15 minutes the exceptions is thrown, so setting to 0 or -1 has no effect:
So this makes the query stop after 10 secs:
-Doracle.net.CONNECT_TIMEOUT=10000 -Doracle.net.READ_TIMEOUT=10000 -Doracle.jdbc.ReadTimeout=10000
But with this stops after 15 minutes:
-Doracle.net.CONNECT_TIMEOUT=-1 -Doracle.net.READ_TIMEOUT=-1 -Doracle.jdbc.ReadTimeout=-1
Setting oracle.net.keepAlive=true as JVM property as #Nirmala suggested doesn’t work.
Setting oracle.jdbc.javaNetNio=false as JVM property as #ibre5041 makes it work. So it points to some problem with the java.nio transport layer.
Anyway, we opened a support issue to Oracle, cause the jdbc api statement.setQueryTimeout(0) should work without having to configure the datasource, I'll put the response when the case is closed.

The query execution could be stopped because of default tcp connection timeout. Can you set keepalive property "oracle.net.keepAlive" to “true” and verify?

java.net.BindException: Address already in use: connect (I did read the others before posting)

I know there are a ton of these posts, but this is a little different. We are using vended code for part of our data processing system, and part of the system sends emails to clients if certain events take place on data insertion or deletion. Recently we have started getting address already in use exceptions. We checked the repository history, and nothing has changed in our code in the last 6 months for this system. We have already tried the typical solutions for this issue including increasing the number of connections allowed to the port with little success. We had a meeting with the vendor, and I asked if anything had changed in their code, and if they would assure that all connections in their code are explicitly closed. They indicated that they are explicitly closing all sockets. However they didn't show us the code so there is no way for us to know if this is true other than taking their word for it. So, the only thing I can think of to do is continue to increase the number of connections to the port until we stop getting bind exceptions. So, what is the industry standard for max number of connections to port 25; is there one? Also if anyone has any other suggestions I would greatly appreciate it? Thanks so much in advance, Robert
20210505112127.716 ERROR m.fiserv.ppx.business.notification.EmailNotifier : MessagingException from notify
javax.mail.MessagingException: Could not connect to SMTP host: SERVER.URL.COM, port: 25;
nested exception is:
java.net.BindException: Address already in use: connect
at com.sun.mail.smtp.SMTPTransport.openServer(SMTPTransport.java:1545)
at com.sun.mail.smtp.SMTPTransport.protocolConnect(SMTPTransport.java:453)
Caused by:
java.net.BindException: Address already in use: connect
at java.net.DualStackPlainSocketImpl.connect0(Native Method)
at java.net.DualStackPlainSocketImpl.socketConnect(DualStackPlainSocketImpl.java:90)
at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:380)
20210505131529.950 ERROR erv.ppx.web.controller.AuditReportViewController : Error while generating HTML
net.sf.jasperreports.engine.JRException: Error writing to OutputStream writer : CorpAdminAuditReport
at net.sf.jasperreports.engine.export.JRHtmlExporter.exportReport(JRHtmlExporter.java:496)
at com.fiserv.ppx.web.controller.AuditReportViewController.generateReport(AuditReportViewController.java:184)
Caused by:
com.ibm.wsspi.webcontainer.ClosedConnectionException: OutputStream encountered error during write
at com.ibm.ws.webcontainer.channel.WCCByteBufferOutputStream.write(WCCByteBufferOutputStream.java:188)
at com.ibm.ws.webcontainer.srt.SRTOutputStream.write(SRTOutputStream.java:97)
20210505140706.240 ERROR com.fiserv.ppx.business.db.DBConnectionUtil : Exception in getting for AppServer connection from DataSource.
com.ibm.websphere.ce.cm.ConnectionWaitTimeoutException: J2CA1010E: Connection not available; timed out waiting for 180,005 seconds.
at com.ibm.ws.rsadapter.AdapterUtil.toSQLException(AdapterUtil.java:1680)
at com.ibm.ws.rsadapter.jdbc.WSJdbcDataSource.getConnection(WSJdbcDataSource.java:661)
at com.ibm.ws.rsadapter.jdbc.WSJdbcDataSource.getConnection(WSJdbcDataSource.java:611)
Caused by:
com.ibm.websphere.ce.j2c.ConnectionWaitTimeoutException: J2CA1010E: Connection not available; timed out waiting for 180,005 seconds.
at com.ibm.ejs.j2c.FreePool.createOrWaitForConnection(FreePool.java:1781)
at com.ibm.ejs.j2c.PoolManager.reserve(PoolManager.java:3834)
at com.ibm.ejs.j2c.PoolManager.reserve(PoolManager.java:3082)
20210505140731.341 ERROR com.fiserv.ppx.business.db.DBConnectionUtil : Exception in getting for AppServer connection from DataSource.
com.ibm.websphere.ce.cm.ConnectionWaitTimeoutException: J2CA1010E: Connection not available; timed out waiting for 180,010 seconds.
at com.ibm.ws.rsadapter.AdapterUtil.toSQLException(AdapterUtil.java:1680)
at com.ibm.ws.rsadapter.jdbc.WSJdbcDataSource.getConnection(WSJdbcDataSource.java:661)
at com.ibm.ws.rsadapter.jdbc.WSJdbcDataSource.getConnection(WSJdbcDataSource.java:611)
Caused by:
com.ibm.websphere.ce.j2c.ConnectionWaitTimeoutException: J2CA1010E: Connection not available; timed out waiting for 180,010 seconds.
at com.ibm.ejs.j2c.FreePool.createOrWaitForConnection(FreePool.java:1781)
at com.ibm.ejs.j2c.PoolManager.reserve(PoolManager.java:3904)
at com.ibm.ejs.j2c.PoolManager.reserve(PoolManager.java:3082)
20210505140731.341 ERROR com.fiserv.ppx.sso.controller.SSOController : SSO Configuration error
java.lang.NullPointerException
at com.fiserv.ppx.business.db.PPXDbTransactionManager.<init>(PPXDbTransactionManager.java:60)
at com.fiserv.ppx.sso.impl.SSOLoginAuthenticator.authenticateSSOUser(SSOLoginAuthenticator.java:157)

odd SQLException - Could not retrieve transation read-only status server

I have a Quartz Job that executes a Stored Procedure in my MySQL database once every 5 minutes, and for some reason, 1 out of 3 executions fails and gives this weird exception. I have searched and searched for what this exception means, but I could not find a solution. Here is the full stack trace:
java.sql.SQLException: Could not retrieve transation read-only status server
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1078)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:989)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:975)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:920)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:951)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:941)
at com.mysql.jdbc.ConnectionImpl.isReadOnly(ConnectionImpl.java:3939)
at com.mysql.jdbc.ConnectionImpl.isReadOnly(ConnectionImpl.java:3910)
at com.mysql.jdbc.PreparedStatement.checkReadOnlySafeStatement(PreparedStatement.java:1258)
at com.mysql.jdbc.CallableStatement.checkReadOnlySafeStatement(CallableStatement.java:2656)
at com.mysql.jdbc.PreparedStatement.execute(PreparedStatement.java:1278)
at com.mysql.jdbc.CallableStatement.execute(CallableStatement.java:920)
at com.mchange.v2.c3p0.impl.NewProxyCallableStatement.execute(NewProxyCallableStatement.java:3044)
at org.deadmandungeons.website.tasks.RankUpdateTask.execute(RankUpdateTask.java:30)
at org.quartz.core.JobRunShell.run(JobRunShell.java:202)
at org.quartz.simpl.SimpleThreadPool$WorkerThread.run(SimpleThreadPool.java:573)
Caused by: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure
The last packet successfully received from the server was 1,198,219 milliseconds ago. The last packet sent successfully to the server was 950,420 milliseconds ago.
at sun.reflect.GeneratedConstructorAccessor43.newInstance(Unknown Source)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.lang.reflect.Constructor.newInstance(Constructor.java:526)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:411)
at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1121)
at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:3673)
at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:3562)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:4113)
at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:2570)
at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2731)
at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2812)
at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2761)
at com.mysql.jdbc.StatementImpl.executeQuery(StatementImpl.java:1612)
at com.mysql.jdbc.ConnectionImpl.isReadOnly(ConnectionImpl.java:3933)
... 9 more
Caused by: java.net.SocketException: Connection timed out
at java.net.SocketInputStream.socketRead0(Native Method)
at java.net.SocketInputStream.read(SocketInputStream.java:150)
at java.net.SocketInputStream.read(SocketInputStream.java:121)
at com.mysql.jdbc.util.ReadAheadInputStream.fill(ReadAheadInputStream.java:114)
at com.mysql.jdbc.util.ReadAheadInputStream.readFromUnderlyingStreamIfNecessary(ReadAheadInputStream.java:161)
at com.mysql.jdbc.util.ReadAheadInputStream.read(ReadAheadInputStream.java:189)
at com.mysql.jdbc.MysqlIO.readFully(MysqlIO.java:3116)
at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:3573)
... 17 more
So I figured it is timing out because it thinks the MySQL server is in read-only status?
This only happens for this quartz job, and not any other time when I communicate with the database. This execution is of course happening in another thread, but I don't think that would have anything to do with it.
Why would it think the server was in read-only mode?
Also, I don't think "transation" is a word, so there's that...

Sorry for posting on old thread,
As stack trace says
com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure
This implies the link between JDBC and DB is broken.As per your observation you say 1 out of 3 job invocations fails.
You have these jobs scheduled every 5 minutes and as per trace the last successful message sent to server is ~15 minutes before.
Hence I suspect either
You are procedure is not returning (waiting on something)
The JDBC connection has been invalidated by the firewall/ proxy
It will interesting to see the how connections are managed, As per logs I see you are using c3p0.
You can try setting unreturnedConnectionTimeout and debugUnreturnedConnectionStackTraces. This will give you more insight into connection leaks or db calls which are taking long.

Research takes nowhere, as you guys said, but the error shows what seems to be a Database being populated by two applications at the same time.
Do you have admin privileges on this MySQL server? If you do, you should try setting
FLUSH TABLES WITH READ LOCK;
SET GLOBAL READ_ONLY=ON;
as a test to reproduce the error. Just to warn you, this command makes your database unwritable, so you will not be able to add data in it until you revert this configuration, obviously with
SET GLOBAL READ_ONLY=0;
UNLOCK TABLES;
If the result of this test is positive (same error had been reproduced), you should try isolating applications that are storing data on your database, to find out which one is conflicting with Quartz.
I'm sorry for being vague, but I hope it gives you some help...

Unable to get resource from jedis

After running my application, i am getting this error after around 5 mins.
Even though i am returning the resource after use, i keep getting this.
I have built jedis-2.2.2-SNAPSHOT.jar from the jedis code base, since its not released yet
I had set the minIdle = 100, maxIdle=200 & maxActive=200. At the time of this exception, the connection count to redis was 122 from my application
redis.clients.jedis.exceptions.JedisConnectionException: Could not get a resource from the pool
at redis.clients.util.Pool.getResource(Pool.java:42)
Caused by: java.util.NoSuchElementException: Timeout waiting for idle object
at org.apache.commons.pool2.impl.GenericObjectPool.borrowObject(GenericObjectPool.java:442)
at org.apache.commons.pool2.impl.GenericObjectPool.borrowObject(GenericObjectPool.java:360)
at redis.clients.util.Pool.getResource(Pool.java:40)
... 6 more

Did you check that redis is still up & running ?
If not, investigate why it died.
try a redis-cli in a terminal if you can. "info" would give you more details.

How to solve MySQL jdbc socket closed SocketException?

There is on error that appears in my log file every time:
com.mysql.jdbc.CommunicationsException: Communications link failure due to underlying exception:
** BEGIN NESTED EXCEPTION **
java.net.SocketException
MESSAGE: Socket closed
STACKTRACE:
java.net.SocketException: Socket closed
at java.net.SocketInputStream.socketRead0(Native Method)
at java.net.SocketInputStream.read(SocketInputStream.java:129)
at com.mysql.jdbc.util.ReadAheadInputStream.fill(ReadAheadInputStream.java:113)
at com.mysql.jdbc.util.ReadAheadInputStream.readFromUnderlyingStreamIfNecessary(ReadAheadInputStream.java:160)
at com.mysql.jdbc.util.ReadAheadInputStream.read(ReadAheadInputStream.java:188)
at com.mysql.jdbc.MysqlIO.readFully(MysqlIO.java:1994)
at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:2411)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:2916)
at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:1631)
at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:1723)
at com.mysql.jdbc.Connection.execSQL(Connection.java:3250)
at com.mysql.jdbc.Connection.execSQL(Connection.java:3179)
at com.mysql.jdbc.Statement.executeQuery(Statement.java:1207)
at com.mchange.v2.c3p0.impl.NewProxyStatement.executeQuery(NewProxyStatement.java:35)
It happens always in the same point of the code, when the application does a specific query in the MySQL database.
The query is LIKE THIS:
SELECT M.*, O.id
FROM order_message M
INNER JOIN orders O ON M.order_id = O.id
WHERE O.seller_id = 14224 AND M.sender_user_id <> 14224
ORDER BY M.creation_date DESC
LIMIT 5
I noticed (by EXPLAINING this query) that it always use temporary/filesort to execute. All indexes are properly created and I think these is no way to improve this, but I suspect the query performance or resource utilization is causing the exception error.
I am using amazon RDS

The problem was that my connection pool was configured in a way that any database connection that took longer than 10 seconds would be dropped by the connection pool (c3p0). I was using the unreturnedConnectionTimeout parameter.
The c3p0 documentation page discourage to use this parameter. Ideally, all connections should be properly closed (and thus returned to the pool)
http://www.mchange.com/projects/c3p0/#unreturnedConnectionTimeout
I have increased the parameter to 60 seconds and the problem get solved.