JSP application closing connection MySQL database occasionally - mysql

Question

I inherited some old WebApplication deployed to ElasticBeanstalk application in AWS, The Application code is written in a mixture of JSP and Java. running in a tomcat 8.5 server
Also, for every 5min the application connects to the MySQL database and displays the contents in a webpage,
now the issue is sometime it displays the webpage empty, when its empty I can see error logs like this
13: if(refresh==null){
14: refresh = "60";
15: }
16: Sql mysql = new Sql(Constants.strJDBC);
17:
18:
19: if(request.getParameter("section")==null){
Stacktrace:] with root cause
java.sql.SQLException: Server connection failure during transaction. Due to underlying exception: 'java.net.SocketException: java.net.ConnectException: Connection timed out (Connection timed out)'.
** BEGIN NESTED EXCEPTION **
java.net.SocketException
MESSAGE: java.net.ConnectException: Connection timed out (Connection timed out)
STACKTRACE:
java.net.SocketException: java.net.ConnectException: Connection timed out (Connection timed out)
at com.mysql.jdbc.StandardSocketFactory.connect(StandardSocketFactory.java:156)
at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:284)
at com.mysql.jdbc.Connection.createNewIO(Connection.java:2706)
at com.mysql.jdbc.Connection.<init>(Connection.java:1485)
at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:266)
at org.apache.commons.dbcp.DriverConnectionFactory.createConnection(DriverConnectionFactory.java:38)
at org.apache.commons.dbcp.PoolableConnectionFactory.makeObject(PoolableConnectionFactory.java:294)
at org.apache.commons.dbcp.BasicDataSource.validateConnectionFactory(BasicDataSource.java:1247)
at org.apache.commons.dbcp.BasicDataSource.createDataSource(BasicDataSource.java:1221)
at org.apache.commons.dbcp.BasicDataSource.getConnection(BasicDataSource.java:880)
at core.Sql.getDbConn(Sql.java:48)
at core.Sql.<init>(Sql.java:19)
at org.apache.jsp._1.callBackLog_jsp._jspService(callBackLog_jsp.java:134)
at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:764)
at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:465)
at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:383)
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:331)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:764)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:196)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:97)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:542)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:135)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:81)
at org.apache.catalina.valves.RemoteIpValve.invoke(RemoteIpValve.java:769)
at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:698)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:78)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:366)
at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:639)
at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:65)
at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:847)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1680)
at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)
at org.apache.tomcat.util.threads.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1191)
at org.apache.tomcat.util.threads.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:659)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Thread.java:750)
** END NESTED EXCEPTION **
Attempted reconnect 3 times. Giving up.
at com.mysql.jdbc.Connection.createNewIO(Connection.java:2781)
at com.mysql.jdbc.Connection.<init>(Connection.java:1485)
at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:266)
at org.apache.commons.dbcp.DriverConnectionFactory.createConnection(DriverConnectionFactory.java:38)
at org.apache.commons.dbcp.PoolableConnectionFactory.makeObject(PoolableConnectionFactory.java:294)
at org.apache.commons.dbcp.BasicDataSource.validateConnectionFactory(BasicDataSource.java:1247)
at org.apache.commons.dbcp.BasicDataSource.createDataSource(BasicDataSource.java:1221)
at org.apache.commons.dbcp.BasicDataSource.getConnection(BasicDataSource.java:880)
at core.Sql.getDbConn(Sql.java:48)
at core.Sql.<init>(Sql.java:19)
at org.apache.jsp._1.callBackLog_jsp._jspService(callBackLog_jsp.java:134)
at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:764)
at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:465)
at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:383)
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:331)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:764)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:196)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:97)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:542)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:135)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:81)
at org.apache.catalina.valves.RemoteIpValve.invoke(RemoteIpValve.java:769)
at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:698)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:78)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:366)
at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:639)
at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:65)
at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:847)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1680)
at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)
at org.apache.tomcat.util.threads.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1191)
at org.apache.tomcat.util.threads.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:659)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Thread.java:750)
we are using mysql-connector-java-3.1.14-bin.jar and in the context.xml file I can see the following configuration
maxActive="500" maxIdle="20" maxWait="10000" type="javax.sql.DataSource" url="jdbc:mysql://<dabase-endpoint>:3306/<database-name>?autoReconnect=true"
in the following link https://tomcat.apache.org/tomcat-7.0-doc/jndi-datasource-examples-howto.html i can see maxIdle time is set to 30, will it help if i change our maxIdle from 20 to 30.
thanks in advance