Use Java EE deployment descriptors to define context parameters

This rule flags Context <Parameter> elements found in the META-INF/context.xml file.

Apache Tomcat allows Context <Parameter> elements to be defined in these locations:

• The META-INF/context.xml file
• The application XML configuration file in Tomcat conf directory
• The <Host> element in the conf/server.xml

The migration tool only migrates parameter elements in the META-INF/context.xml file. Parameter information defined in the other locations can be copied to the META-INF/context.xml file in order for it to be processed.

If a WEB-INF/web.xml exists in the web project:

Context <Parameter> elements will be flagged under either of the following conditions:

• The entry does not have a matching entry in the web.xml file.
• The entry has a different value than the matching entry in the web.xml and its override flag is set to false.

A quick fix for this rule is available in the source scanner. The quick fix will add a new <context-param> element in the web.xml file which represents the Context <Parameter> element if it does not already exist in the web.xml file. If the entry exists, it will be updated.

If the WEB-INF/web.xml does not exist:

All Context <Parameter> elements will be flagged.

The quick fix will create a WEB-INF/web.xml file that includes the appropriate <context-param> elements if the web project is at Java EE 5 or higher. The quick fix will report an error if the web project is at J2EE 1.4 or lower.

For example, consider a META-INF/context.xml file with the following content:

<Parameter description="Trigger because it does not exist" name="newEntry" override="false" value="abc123"/> <Parameter description="Trigger because of different value" name="parameter_1" override="false" value="new Value"/> <Parameter description="Will not trigger because of override set to true" name="parameter_2" override="true" value="123"/>

with the following web.xml file in the application:

<context-param> <description>Trigger because of different value</description> <param-name>parameter_1</param-name> <param-value>oldValue</param-value> </context-param> <context-param> <description>Will not trigger because of override set to true</description> <param-name>parameter_2</param-name> <param-value>123456789</param-value> </context-param>

After the quick fix is applied, the web.xml will be updated to contain:

<context-param> <description>Trigger because it does not exist</description> <param-name>newEntry</param-name> <param-value>abc123</param-value> </context-param> <context-param> <description>Trigger because of different value</description> <param-name>parameter_1</param-name> <param-value>new Value</param-value> </context-param> <context-param> <description>Will not trigger because of override set to true</description> <param-name>parameter_2</param-name> <param-value>123456789</param-value> </context-param>

For additional information on the context parameter in Tomcat see:

• Apache Tomcat Configuration Reference - Context Parameters.