Ubuntu Tomcat7 java.lang.ClassNotFoundException: org.apache.tomcat.dbcp.dbcp.BasicDataSourceFactory

The library tomcat-dbcp-7.0.30.jar from repositories is corrupted.

Replace it with:

sudo wget -O /usr/share/java/tomcat-dbcp-7.0.30.jar http://search.maven.org/remotecontent?filepath=org/apache/tomcat/tomcat-dbcp/7.0.30/tomcat-dbcp-7.0.30.jar

The cause is a issue in the Ubuntu build/package process for Tomcat7. If I understand the issue correctly, Apache builds tomcat-dbcp.jar from binary files, while Ubuntu builds packages only from source. The Ubuntu project ends up needing to change the Java package name, which tends to break things for us poor users. The gory details may be found at the Ubuntu issues list.

The solution I found is to name the data source factory when I define the resource. In one case, I have a META-INF/context.xml file that contains:

<Resource name="jdbc/myDataSource"
    auth="Container"
    type="javax.sql.DataSource"
    driverClassName="com.mysql.jdbc.Driver"
    url="jdbc:mysql://localhost:3306/myDatabase"
    username="username" password="password"
    validationQuery="SELECT COUNT(*) FROM MY_TABLE"
    factory="org.apache.commons.dbcp.BasicDataSourceFactory" />

The critical element is the "factory" declaration, which overrides the built-in default.

On our production machines, the resource is defined in the GlobalNamingResources element of the server.xml file. Specifying the factory is only needed on the Ubuntu systems.