raminorujov / ec2-tomcat8-dbcp-problem

AWS Amazon Linux AMI Tomcat 8 DBCP problem solution

AWS Amazon Linux AMI Tomcat 8 DBCP problem solution

Problem

I encountered this issue in 2018, while deploying my app on AWS EC2. If you use "64bit Amazon Linux 2017.09 v2.7.5" (EC2 image ID: ami-69000209), embedded Tomcat 8 doesn't contain DBCP database connection pool jar files, your JNDI datasource database connection will fail with the exception java.lang.ClassNotFoundException: org.apache.tomcat.dbcp.dbcp2.BasicDataSourceFactory

Solution steps

Step1. Add the following maven dependencies( Apache Commons DBCP 2.x and Apache Commons DBCP 2.x).

<dependency>
	<groupId>org.apache.commons</groupId>
	<artifactId>commons-dbcp2</artifactId>
	<version>2.2.0</version>
</dependency>
<dependency> 
	<groupId>org.apache.commons</groupId>
	<artifactId>commons-pool2</artifactId>
	<version>2.5.0</version>
</dependency>

If you don't use Maven, you can copy commons-dbcp2-2.2.0.jar and commons-pool2-2.5.0.jar files into project's WEB-INF/lib folder.

Step 2. Add factory="org.apache.commons.dbcp2.BasicDataSourceFactory" into your META-INF/context.xml files.

<?xml version="1.0" encoding="UTF-8"?>
<Context>
    <Resource name="jdbc/mdbwebdb"
              auth="Container"
              type="javax.sql.DataSource"
              username="db-user"
              password="db-pwd"
              driverClassName="jdbc-driver"
              url="jdbc-url"
              factory="org.apache.commons.dbcp2.BasicDataSourceFactory"
              initialSize="2"
              maxTotal="20"
              minIdle="2"
              maxIdle="20"
              maxWaitMillis="3000"
              defaultAutoCommit="false"
              timeBetweenEvictionRunsMillis="30000"
              removeAbandonedOnBorrow="true"
              removeAbandonedOnMaintenance="true"
              removeAbandonedTimeout="60"
              logAbandoned="true"
    ></Resource>
</Context>

Please, consider that some properties are renamed.

• maxActive = maxTotal
• maxWait = maxWaitMillis
• removeAbandoned = removeAbandonedOnBorrow, removeAbandonedOnMaintenance

References:

1.https://forums.aws.amazon.com/thread.jspa?messageID=721145 2.http://tomcat.apache.org/migration-8.html#Database_Connection_Pooling 3.http://commons.apache.org/proper/commons-dbcp/configuration.html