XDoclet Tasks, Subtasks, and Templates

Because the tasks act as an encapsulation construct, it is only natural to expect that there are subcomponents or subtasks available within each of the core tasks.

Subtasks

Each task will have a number of subtasks that instruct XDoclet to invoke a specific template used in the code generation step. If you look back at our Ant build.xml script, you will find several subtasks listed for our EJB code generation. These subtasks were:

<localinterface/> 
<localhomeinterface/> 
<remoteinterface/>
<homeinterface/>

In order to help you understand what XDoclet is doing during the code generation, consider the code for the <localinterface> subtask found in the following listing. As you can see, the subtask relates to an actual class within the EJB module.

public class LocalInterfaceSubTask extends AbstractEjbCodeGeneratorSubTask
{
    public final static String DEFAULT_LOCAL_CLASS_PATTERN = "{0}Local";

    protected static String DEFAULT_TEMPLATE_FILE = "resources/local.xdt";

    /**
     * A configuration parameter for specifying the local interface name pattern. By default the value is used for
     * deciding the local interface name. {0} in the value mean current class's symbolic name which for an EJBean is the
     * EJB name.
     *
     * @see   #getLocalClassPattern()
     */
    protected String localClassPattern;


    /**
     */
    public LocalInterfaceSubTask()
    {
        setTemplateURL(getClass().getResource(DEFAULT_TEMPLATE_FILE));
        setDestinationFile(getLocalClassPattern() + ".java");
        addOfType("javax.ejb.EntityBean");
        addOfType("javax.ejb.SessionBean");
    }

...

In this partial code listing, we see the declaration of the LocalInterfaceSubTask that will be executed if the <localinterface> subtask element is found within our Ant build script. There are appropriate classes for all of the subtasks within XDoclet.

Templates

Templates are files that contain some code and some XML-like syntax used in the generation of the final source code. The following listing shows a template used in the <localinterface> subtask.

/*
 * <XDtI18n:getString bundle="xdoclet.modules.ejb.XDocletModulesEjbMessages" resource="do_not_edit"/>
 */
package <XDtPackage:packageOf><XDtEjbIntf:componentInterface type="local"/></XDtPackage:packageOf>;

/**
 * <XDtI18n:getString bundle="xdoclet.modules.ejb.XDocletModulesEjbMessages" 
resource="local_interface_for" arguments="<XDtEjb:ejbName/>"/>
<XDtClass:classCommentTags indent="0"/> 
*/
public interface <XDtClass:classOf><XDtEjbIntf:componentInterface type="local"/></XDtClass:classOf>
   extends <XDtEjbIntf:extendsFrom type="local"/><XDtClass:ifHasClassTag tagName="ejb:bean" 
paramName="local-business-interface">, <XDtClass:classTagValue tagName="ejb:bean" 
paramName="local-business-interface"/></XDtClass:ifHasClassTag>
{
  <XDtClass:ifDoesntHaveClassTag tagName="ejb:bean" paramName="local-business-interface">
   <XDtMethod:forAllMethods>
    <XDtEjbIntf:ifIsInterfaceMethod superclasses="false" interface="local">
<XDtMethod:methodComment indent="3"/>
   public <XDtMethod:methodType/> <XDtMethod:methodName/>( <XDtParameter:parameterList/> ) 
<XDtMethod:exceptionList/>;

    </XDtEjbIntf:ifIsInterfaceMethod>
   </XDtMethod:forAllMethods>
  </XDtClass:ifDoesntHaveClassTag>

   <XDtMerge:merge file="local-custom.xdt">
   </XDtMerge:merge>
}