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     	  <h2><font face="Arial,Helvetica"><font color="#ffffff">
     	  &nbsp;EGF Tutorial - Pattern. First steps.
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 <p class="Para">This first tutorial explains how to create and execute simple patterns with EGF. A pattern is a solution to a recurrent generation problem. A pattern is based on a language, for instance Jet for model-to-text transformations. The pattern technique allows pattern inheritance, delegation to other patterns in order to elaborate reusable and customizable generation solutions.</p>

 <br/>

 <h2 class="Head">1. Creation of pattern</h2>

 <h3 class="Head">1.1. Comprehension</h3>
 <p class="Para"><i>Pattern organization</i>. Patterns are organized by pattern libraries. A <b>pattern library</b> contains a set of patterns and a set of pattern libraries.</p>
 <p class="Para"><i>Pattern nature</i>. A <b>pattern nature</b> indicates which language the pattern implementation conforms to (e.g. Java, Jet).</p>
 <p class="Para"><i>Pattern views</i>. A pattern is visualized with three different folders: 1) Overview, 2) <b>Specification</b> which represents the external view of a pattern, 3) <b>Implementation</b> which represents the internal view of a pattern and where the pattern is implemented.</p>


 <h3 class="Head">1.2. Practice</h3>

 <p class="Para">The sequence of actions to <i>create a pattern</i>:</p>
 <ul CLASS="UnorderedList">
     <li CLASS="Item">Create the <i>viewpoints</i> node - On a factory component, Commands: <i>[New Child][Viewpoint Container]</i></li>
     <li CLASS="Item">Create the <i>Pattern Viewpoint</i> node - On the <i>Viewpoint Container</i> node, Commands: <i>[New Child][Pattern Viewpoint]</i></li>
     <li CLASS="Item">Create a pattern library - On the pattern viewpoint, Commands: <i>[New Child][Library]</i></li>
     <li CLASS="Item">Next, create a <i>pattern</i> - On the pattern library, Commands: <i>[New Child][JetNature Pattern | JavaNature Pattern]</i></li>
     <li CLASS="Item">Edit the pattern -  On the pattern, Commands: <i>[Double-click]</i> or <i>[Right-Click][Open]</i></li>
     <li CLASS="Item">Set the pattern name</li>
 </ul>

 <h3 class="Head">1.3. Application</h3>
 <p class="Para">Create a pattern with the Jet nature.</p>

 <p align="left">
   <img src="./images/egf_tut_pattern_1_1.png" alt="New pattern"/>
 </p>
 <p align="left"><i>Figure 1. Example of new pattern</i></p>

 <br/>

 <h2 class="Head">2. Definition of the pattern specification</h2>

 <h3 class="Head">2.1. Comprehension</h3>

 <p class="Para"><i>Specification view</i>. This view enables to set 1) the super-pattern of the current pattern when pattern inheritance is needed, 2) the pattern nature already set during the pattern creation, 3) the pattern parameters.</p>
 <p class="Para"><i>Pattern query and parameter</i>. The pattern applies queries over a resource that the pattern consumes, for instance a model. Each query record is successively stored in a parameter. The record process is described in the pattern implementation.</p>
 <p class="Para"><i>Pattern query</i>. EGF proposes a default model query. The query list is extensible.</p>
 <p class="Para"><i>Pattern parameter</i>. The pattern type is either a class defined in an ecore model or a Java type (class or interface).</p>


 <h3 class="Head">2.2. Practice</h3>
 <p class="Para">The sequence of actions to define <i>pattern parameters and their query</i>:</p>
 <ul CLASS="UnorderedList">
     <li CLASS="Item">In the Specification view, in the Parameters section - Command: <i>[+]</i>, set the parameter name</li>
     <li CLASS="Item">Set the parameter type - Command: choose the model and a class type</li>
     <li CLASS="Item">Set the query - Command: choose the query, for instance <i>Basic query</i></li>
 </ul>

 <h3 class="Head">2.3. Application</h3>
 <p class="Para">Create an EClass parameter with the <i>Basic query</i> to navigate over the model.</p>

 <p align="left">
   <img src="./images/egf_tut_pattern_1_2.png" alt="Pattern Specification View"/>
 </p>
 <p align="left"><i>Figure 2. Pattern Specification View</i></p>
 <br/>


 <h2 class="Head">3. Definition of the pattern implementation</h2>

 <h3 class="Head">3.1. Comprehension</h3>

 <p class="Para"><i>Implementation view</i>. This view enables to define pattern methods, the method orchestration, and local variables.</p>
 <p class="Para"><i>Pattern methods</i>. Four methods are predefined: header, init, preCondition and footer. Header is used for instance to declare the Jet declaration, init for the initialization of local variables (cf. explanation below), preCondition to filter records onto a query result. The user creates as many as methods s/he wants to implement the pattern. Each pattern method contents is supposed to conform to the pattern nature, for instance Jet-based code.</p>
 <p class="Para"><i>Pattern method orchestration</i>. The method orchestration defines the order to call available methods and patterns: methods local to the current pattern, methods from the super-patterns, pattern call with parameter context passing, pattern call with injection.</p>
 <p class="Para"><i>Pattern variables</i>. The pattern variables are accessible by any method of the current pattern. The type is either a class defined in an ecore model or a Java type (class or interface). Pattern variables can be initialized in the <i>init</i> method, update and used in the pattern methods.</p>


 <h3 class="Head">3.2. Practice</h3>
 <p class="Para">The sequence of actions to manage the <i>implementation methods</i>:</p>
 <ul CLASS="UnorderedList">
     <li CLASS="Item">Use the palette to add/delete/rename/reorder a method.</li>
     <li CLASS="Item">To edit method, double-click on a method of the <i>Implementation methods</i> list. Next, a pattern templates editor allows editing any other method.</li>
 </ul>

 <p class="Para">The sequence of actions to manage <i>variables</i>:</p>
 <ul CLASS="UnorderedList">
     <li CLASS="Item">In the variables, to add a variable, Command: <i>[+]</i>, set the parameter name</li>
     <li CLASS="Item">Set the parameter type - Command: click on the type and select the model / Java type</li>
 </ul>


 <p class="Para">The sequence of actions to manage the <i>method orchestration</i>:</p>
 <ul CLASS="UnorderedList">
     <li CLASS="Item">Use the palette to add/delete/rename/reorder methods</li>
     <li CLASS="Item">Drag and drop a method from the <i>Implementation methods</i> list</li>
     <li CLASS="Item">For a super-method call, after clicking on <i>+</i>, choose the <i>method call</i> option, and next select the super-method.</li>
 </ul>


 <h3 class="Head">3.3. Application</h3>
 <p class="Para">Implement the default body method. Add the following Jet code:</p>
 				<font color="777777"><pre>
 Hello &lt;%= parameter.getName() %&gt;!
 				</pre></font>
 <p class="Para">Drag and drop the method in the pattern orchestration part.</p>


 <br/>

 <h2 class="Head">4. Configuration of the pattern execution</h2>

 <h3 class="Head">4.1. Comprehension - Principle of pattern execution</h3>
 <p class="Para">The following figure depicts how patterns are applied onto a domain resource.</p>

 <p align="left">
   <img src="./images/egf_tut_pattern_1_3.png" alt="Pattern Execution"/>
 </p>
 <p align="left"><i>Figure 3. Pattern Execution</i></p>

 <p class="Para"><i>Pattern strategies</i>. A pattern strategy indicates how to apply patterns onto a resource. For instance, a pattern-oriented strategy successively applies a set of patterns onto a resource; a model-oriented strategy applies a set of patterns successively onto each model element. The model-driven strategy takes care of the model element order while the pattern-oriented strategy does not.</p>
 <p class="Para"><i>Tasks to execute patterns</i>. A task must be introduced in order to put in action all the elements described. This task must know:
   <ol CLASS="UnorderedList">
     <li> The resource applied on the patterns, for instance a model,</li>
     <li> The selection of pattern(s) or the pattern library(ies),</li>
     <li> The reporter (see below).</li>
   </ol>
 </p>

 <p class="Para"><i>Domain resource</i>. Patterns are applied onto a resource, such as a domain model.</p>

 <p class="Para"><i>Pattern execution engines</i>. Patterns have a nature (e.g., Jet, Java). Then, at execution time, an engine executes a pattern according its nature. On the pattern flow, different pattern execution engines can be activated.</p>

 <p class="Para"><i>Reporter</i>. A reporter is typically useful for model-to-text transformation. Each pattern provides an output result that must be consolidated in one or several files. A reporter serves to report the result of the pattern implementation, for instance on the console or in a file.</p>
 <br/>

 <h3 class="Head">4.2. Practice</h3>
 <p class="Para">A task is used to execute a pattern or a set of patterns. This task must know: 1) the domain model, 2) the pattern or pattern library list, 3) the pattern strategy, and 4) the reporter. This tutorial uses the <i>Model-driven pattern strategy</i>. The use of pattern reporter is explained below.</p>
 <p class="Para">The sequence of actions to create a task for pattern execution:</p>
 <ul CLASS="UnorderedList">
     <li CLASS="Item"><i>Domain creation</i>. This step can be reused independently of the pattern usage.</li>
     <ul CLASS="UnorderedList">
         <li CLASS="Item">Step 1. Creation of the domain reference</li>
         <ul CLASS="UnorderedList">
             <li CLASS="Item">Creation of the domain viewpoint where domains are declared - On the Viewpoint Container, Command: [New Child][Domain Viewpoint]</li>
             <li CLASS="Item">Creation of a domain reference - On the Domain Viewpoint, Command: [New Child][URI]. Next, in the Uri property, providing a Uri like <i>platform:/plugin/org.eclipse.egf.model/model/Fcore.ecore</i></li>
         </ul>
         <li CLASS="Item">Step 2. Creation of a domain parameter</li>
         <ul CLASS="UnorderedList">
             <li CLASS="Item">Creation of a domain reference as a production plan parameter - On the production plan, Command: [New Child][Orchestration Parameter Container]</li>
             <li CLASS="Item">Creation of a parameter - On the Orchestration Parameter Container, Commands: [New Child][Orchestration Parameter]; Set the parameter name; Set the Domain property to the Uri created just before</li>
         </ul>
     </ul>
     <br/>
     <li CLASS="Item"><i>Configuration of the pattern call</i>.</li>
     <ul CLASS="UnorderedList">
         <li CLASS="Item">Creation of the pattern execution task - On the Production Plan node, Command: [Right-Click][Invoke Activity], and choose the <i>Model driven pattern strategy task [Task Java]</i></li>
         <li CLASS="Item">Remove the <i>pattern.execution.reporter</i>, <i>pattern.call.back.handler</i> and <i>pattern.modeldriven.visitor</i> contracts</li>
         <li CLASS="Item">Set the domain identification - On the new Activity / Invocation Contract Container / domain Invocation Contract, Command: 1) Set the Orchestration Parameter to the Orchestration Parameter newly created</li>
         <li CLASS="Item">Set the pattern library - On the new Activity / Invocation Contract Container / pattern.ids Invocation Contract, Command: [New Child][Type Pattern List]; Next, [Click on the Elements Property], select the pattern library newly created</li>
     </ul>
 </ul>

 <br/>


 <h3 class="Head">4.3. Application</h3>
 <p class="Para">Create a pattern task invocation as described above. Example of domain: <i>platform:/plugin/org.eclipse.egf.model/model/Fcore.ecore</i>.</p>

 <p class="Para">Finally, execute the factory component. The output is displayed on the console.</p>

 <br/>


 <h3 class="Head">4.4. Fixing pattern method errors</h3>
 <p class="Para">Patterns to be compiled are compiled when a pattern is saved. Errors may be raised and, as a consequence, the pattern execution would fail. Then:</p>
 <ul CLASS="UnorderedList">
     <li CLASS="Item">At anytime, in order to regenerate pattern classes and methods: 1) delete the packages under the project <i>generated</i> folder, 2) right-click on the Pattern viewpoint, and apply the [Update generated elements] command on the Pattern viewpoint.</li>
     <li CLASS="Item">Fixing the errors. Locate the errors in the generated methods, update the pattern methods accordingly, and save the pattern methods.</li>
 </ul>

 <br/>

 <h3 class="Head">4.5. Comprehension - Pattern Reporter</h3>
 <p class="Para"><i>Reporter class</i>. A reporter is a Java class which implements the PatternExecutionReporter class.</p>
 <p class="Para"><i>Collecting the result</i>. There are two methods to collect the execution result of one pattern: 1) the <i>loopFinished</i> method collects the result for one pattern and for one query tuple, 2) the <i>executionFinished</i> method collects the result for one pattern, which is the aggregation of the <i>loopFinished</i> method results.</p>
 <p class="Para"><i>Reporting the result</i>. The result is generally reported in with the selected media, e.g. a file.</p>

 <p class="Para">For more complex reports, refer to the <i>org.eclipse.egf.emf.docgen.html</i> plug-in which examplifies the case of result in a file and a specific folder.</p>

 <br/>

 <h3 class="Head">4.6. Practice</h3>

 <p class="Para">1. Create a reporter Java class like this one:</p>
 				<font color="777777"><pre>
 Package org.eclipse.egf.examples.uc1.reporter;

 import java.util.Map;

 import org.eclipse.egf.core.EGFCorePlugin;
 import org.eclipse.egf.model.pattern.PatternContext;
 import org.eclipse.egf.model.pattern.PatternExecutionReporter;

 public class MyReporter implements PatternExecutionReporter{

 	@Override
 	public void executionFinished(String output, PatternContext context) {
 		// Message on the default console
 		System.out.println("Result of pattern:\n"+output);
 		// Message on the EGF console
 		EGFCorePlugin.getDefault().logInfo("Result of pattern:\n"+output);
 	}

 	@Override
 	public void loopFinished(String output, PatternContext context,
 			Map&lt;String, Object&gt; parameterValues) {
 		// TODO Auto-generated method stub
 	}

 }
 				</pre></font>

 <p class="Para">2. Complete the task with the reporter parameter:
     <ul CLASS="UnorderedList">
         <li CLASS="Item">Add a contract to the task created before</li>
         <li CLASS="Item">For Behaviour/Invoked Contract property, select the <i>pattern.execution.reporter</i> contract (removed before!)</li>
         <li CLASS="Item">Add the <i>Type Pattern Execution Reporter</i> and for value, select the pattern reporter class</li>
     </ul>
 </p>

 <h2 class="Head">5. Pattern translation</h2>
 <p class="Para">The pattern contents is translated into an executable form. This takes into account pattern inheritance and other pattern mechanisms not explained in this tutorial (e.g., pattern call). Next, at execution time, a pattern engine, specific to the pattern nature, executes a pattern.</p>
 <p class="Para">Patterns are translated on the fly. One case requires to manually force pattern rebuild: pattern inheritance. Indeed, children are not notified that a super-pattern in the hierarchy is update. To force this translation:</p>

 <ul CLASS="UnorderedList">
     <li CLASS="Item">On the <i>Pattern viewpoint</i> which contains all the pattern libraries - Command: <i>[Right-Click][Update generated elements]</i> </li>
 </ul>


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	EGF Tutorial - Pattern. First steps.
	</font></font></h2>
	</td>
	</tr>
	</tbody>
	</table>

	<p class="Para">This first tutorial explains how to create and execute simple patterns with EGF. A pattern is a solution to a recurrent generation problem. A pattern is based on a language, for instance Jet for model-to-text transformations. The pattern technique allows pattern inheritance, delegation to other patterns in order to elaborate reusable and customizable generation solutions.</p>

	<br/>

	<h2 class="Head">1. Creation of pattern</h2>

	<h3 class="Head">1.1. Comprehension</h3>
	<p class="Para"><i>Pattern organization</i>. Patterns are organized by pattern libraries. A <b>pattern library</b> contains a set of patterns and a set of pattern libraries.</p>
	<p class="Para"><i>Pattern nature</i>. A <b>pattern nature</b> indicates which language the pattern implementation conforms to (e.g. Java, Jet).</p>
	<p class="Para"><i>Pattern views</i>. A pattern is visualized with three different folders: 1) Overview, 2) <b>Specification</b> which represents the external view of a pattern, 3) <b>Implementation</b> which represents the internal view of a pattern and where the pattern is implemented.</p>


	<h3 class="Head">1.2. Practice</h3>

	<p class="Para">The sequence of actions to <i>create a pattern</i>:</p>
	<ul CLASS="UnorderedList">
	<li CLASS="Item">Create the <i>viewpoints</i> node - On a factory component, Commands: <i>[New Child][Viewpoint Container]</i></li>
	<li CLASS="Item">Create the <i>Pattern Viewpoint</i> node - On the <i>Viewpoint Container</i> node, Commands: <i>[New Child][Pattern Viewpoint]</i></li>
	<li CLASS="Item">Create a pattern library - On the pattern viewpoint, Commands: <i>[New Child][Library]</i></li>
	<li CLASS="Item">Next, create a <i>pattern</i> - On the pattern library, Commands: <i>[New Child][JetNature Pattern \| JavaNature Pattern]</i></li>
	<li CLASS="Item">Edit the pattern - On the pattern, Commands: <i>[Double-click]</i> or <i>[Right-Click][Open]</i></li>
	<li CLASS="Item">Set the pattern name</li>
	</ul>

	<h3 class="Head">1.3. Application</h3>
	<p class="Para">Create a pattern with the Jet nature.</p>

	<p align="left">
	<img src="./images/egf_tut_pattern_1_1.png" alt="New pattern"/>
	</p>
	<p align="left"><i>Figure 1. Example of new pattern</i></p>

	<br/>

	<h2 class="Head">2. Definition of the pattern specification</h2>

	<h3 class="Head">2.1. Comprehension</h3>

	<p class="Para"><i>Specification view</i>. This view enables to set 1) the super-pattern of the current pattern when pattern inheritance is needed, 2) the pattern nature already set during the pattern creation, 3) the pattern parameters.</p>
	<p class="Para"><i>Pattern query and parameter</i>. The pattern applies queries over a resource that the pattern consumes, for instance a model. Each query record is successively stored in a parameter. The record process is described in the pattern implementation.</p>
	<p class="Para"><i>Pattern query</i>. EGF proposes a default model query. The query list is extensible.</p>
	<p class="Para"><i>Pattern parameter</i>. The pattern type is either a class defined in an ecore model or a Java type (class or interface).</p>


	<h3 class="Head">2.2. Practice</h3>
	<p class="Para">The sequence of actions to define <i>pattern parameters and their query</i>:</p>
	<ul CLASS="UnorderedList">
	<li CLASS="Item">In the Specification view, in the Parameters section - Command: <i>[+]</i>, set the parameter name</li>
	<li CLASS="Item">Set the parameter type - Command: choose the model and a class type</li>
	<li CLASS="Item">Set the query - Command: choose the query, for instance <i>Basic query</i></li>
	</ul>

	<h3 class="Head">2.3. Application</h3>
	<p class="Para">Create an EClass parameter with the <i>Basic query</i> to navigate over the model.</p>

	<p align="left">
	<img src="./images/egf_tut_pattern_1_2.png" alt="Pattern Specification View"/>
	</p>
	<p align="left"><i>Figure 2. Pattern Specification View</i></p>
	<br/>


	<h2 class="Head">3. Definition of the pattern implementation</h2>

	<h3 class="Head">3.1. Comprehension</h3>

	<p class="Para"><i>Implementation view</i>. This view enables to define pattern methods, the method orchestration, and local variables.</p>
	<p class="Para"><i>Pattern methods</i>. Four methods are predefined: header, init, preCondition and footer. Header is used for instance to declare the Jet declaration, init for the initialization of local variables (cf. explanation below), preCondition to filter records onto a query result. The user creates as many as methods s/he wants to implement the pattern. Each pattern method contents is supposed to conform to the pattern nature, for instance Jet-based code.</p>
	<p class="Para"><i>Pattern method orchestration</i>. The method orchestration defines the order to call available methods and patterns: methods local to the current pattern, methods from the super-patterns, pattern call with parameter context passing, pattern call with injection.</p>
	<p class="Para"><i>Pattern variables</i>. The pattern variables are accessible by any method of the current pattern. The type is either a class defined in an ecore model or a Java type (class or interface). Pattern variables can be initialized in the <i>init</i> method, update and used in the pattern methods.</p>


	<h3 class="Head">3.2. Practice</h3>
	<p class="Para">The sequence of actions to manage the <i>implementation methods</i>:</p>
	<ul CLASS="UnorderedList">
	<li CLASS="Item">Use the palette to add/delete/rename/reorder a method.</li>
	<li CLASS="Item">To edit method, double-click on a method of the <i>Implementation methods</i> list. Next, a pattern templates editor allows editing any other method.</li>
	</ul>

	<p class="Para">The sequence of actions to manage <i>variables</i>:</p>
	<ul CLASS="UnorderedList">
	<li CLASS="Item">In the variables, to add a variable, Command: <i>[+]</i>, set the parameter name</li>
	<li CLASS="Item">Set the parameter type - Command: click on the type and select the model / Java type</li>
	</ul>


	<p class="Para">The sequence of actions to manage the <i>method orchestration</i>:</p>
	<ul CLASS="UnorderedList">
	<li CLASS="Item">Use the palette to add/delete/rename/reorder methods</li>
	<li CLASS="Item">Drag and drop a method from the <i>Implementation methods</i> list</li>
	<li CLASS="Item">For a super-method call, after clicking on <i>+</i>, choose the <i>method call</i> option, and next select the super-method.</li>
	</ul>


	<h3 class="Head">3.3. Application</h3>
	<p class="Para">Implement the default body method. Add the following Jet code:</p>
	<font color="777777"><pre>
	Hello <%= parameter.getName() %>!
	</pre></font>
	<p class="Para">Drag and drop the method in the pattern orchestration part.</p>


	<br/>

	<h2 class="Head">4. Configuration of the pattern execution</h2>

	<h3 class="Head">4.1. Comprehension - Principle of pattern execution</h3>
	<p class="Para">The following figure depicts how patterns are applied onto a domain resource.</p>

	<p align="left">
	<img src="./images/egf_tut_pattern_1_3.png" alt="Pattern Execution"/>
	</p>
	<p align="left"><i>Figure 3. Pattern Execution</i></p>

	<p class="Para"><i>Pattern strategies</i>. A pattern strategy indicates how to apply patterns onto a resource. For instance, a pattern-oriented strategy successively applies a set of patterns onto a resource; a model-oriented strategy applies a set of patterns successively onto each model element. The model-driven strategy takes care of the model element order while the pattern-oriented strategy does not.</p>
	<p class="Para"><i>Tasks to execute patterns</i>. A task must be introduced in order to put in action all the elements described. This task must know:
	<ol CLASS="UnorderedList">
	<li> The resource applied on the patterns, for instance a model,</li>
	<li> The selection of pattern(s) or the pattern library(ies),</li>
	<li> The reporter (see below).</li>
	</ol>
	</p>

	<p class="Para"><i>Domain resource</i>. Patterns are applied onto a resource, such as a domain model.</p>

	<p class="Para"><i>Pattern execution engines</i>. Patterns have a nature (e.g., Jet, Java). Then, at execution time, an engine executes a pattern according its nature. On the pattern flow, different pattern execution engines can be activated.</p>

	<p class="Para"><i>Reporter</i>. A reporter is typically useful for model-to-text transformation. Each pattern provides an output result that must be consolidated in one or several files. A reporter serves to report the result of the pattern implementation, for instance on the console or in a file.</p>
	<br/>

	<h3 class="Head">4.2. Practice</h3>
	<p class="Para">A task is used to execute a pattern or a set of patterns. This task must know: 1) the domain model, 2) the pattern or pattern library list, 3) the pattern strategy, and 4) the reporter. This tutorial uses the <i>Model-driven pattern strategy</i>. The use of pattern reporter is explained below.</p>
	<p class="Para">The sequence of actions to create a task for pattern execution:</p>
	<ul CLASS="UnorderedList">
	<li CLASS="Item"><i>Domain creation</i>. This step can be reused independently of the pattern usage.</li>
	<ul CLASS="UnorderedList">
	<li CLASS="Item">Step 1. Creation of the domain reference</li>
	<ul CLASS="UnorderedList">
	<li CLASS="Item">Creation of the domain viewpoint where domains are declared - On the Viewpoint Container, Command: [New Child][Domain Viewpoint]</li>
	<li CLASS="Item">Creation of a domain reference - On the Domain Viewpoint, Command: [New Child][URI]. Next, in the Uri property, providing a Uri like <i>platform:/plugin/org.eclipse.egf.model/model/Fcore.ecore</i></li>
	</ul>
	<li CLASS="Item">Step 2. Creation of a domain parameter</li>
	<ul CLASS="UnorderedList">
	<li CLASS="Item">Creation of a domain reference as a production plan parameter - On the production plan, Command: [New Child][Orchestration Parameter Container]</li>
	<li CLASS="Item">Creation of a parameter - On the Orchestration Parameter Container, Commands: [New Child][Orchestration Parameter]; Set the parameter name; Set the Domain property to the Uri created just before</li>
	</ul>
	</ul>
	<br/>
	<li CLASS="Item"><i>Configuration of the pattern call</i>.</li>
	<ul CLASS="UnorderedList">
	<li CLASS="Item">Creation of the pattern execution task - On the Production Plan node, Command: [Right-Click][Invoke Activity], and choose the <i>Model driven pattern strategy task [Task Java]</i></li>
	<li CLASS="Item">Remove the <i>pattern.execution.reporter</i>, <i>pattern.call.back.handler</i> and <i>pattern.modeldriven.visitor</i> contracts</li>
	<li CLASS="Item">Set the domain identification - On the new Activity / Invocation Contract Container / domain Invocation Contract, Command: 1) Set the Orchestration Parameter to the Orchestration Parameter newly created</li>
	<li CLASS="Item">Set the pattern library - On the new Activity / Invocation Contract Container / pattern.ids Invocation Contract, Command: [New Child][Type Pattern List]; Next, [Click on the Elements Property], select the pattern library newly created</li>
	</ul>
	</ul>

	<br/>


	<h3 class="Head">4.3. Application</h3>
	<p class="Para">Create a pattern task invocation as described above. Example of domain: <i>platform:/plugin/org.eclipse.egf.model/model/Fcore.ecore</i>.</p>

	<p class="Para">Finally, execute the factory component. The output is displayed on the console.</p>

	<br/>


	<h3 class="Head">4.4. Fixing pattern method errors</h3>
	<p class="Para">Patterns to be compiled are compiled when a pattern is saved. Errors may be raised and, as a consequence, the pattern execution would fail. Then:</p>
	<ul CLASS="UnorderedList">
	<li CLASS="Item">At anytime, in order to regenerate pattern classes and methods: 1) delete the packages under the project <i>generated</i> folder, 2) right-click on the Pattern viewpoint, and apply the [Update generated elements] command on the Pattern viewpoint.</li>
	<li CLASS="Item">Fixing the errors. Locate the errors in the generated methods, update the pattern methods accordingly, and save the pattern methods.</li>
	</ul>

	<br/>

	<h3 class="Head">4.5. Comprehension - Pattern Reporter</h3>
	<p class="Para"><i>Reporter class</i>. A reporter is a Java class which implements the PatternExecutionReporter class.</p>
	<p class="Para"><i>Collecting the result</i>. There are two methods to collect the execution result of one pattern: 1) the <i>loopFinished</i> method collects the result for one pattern and for one query tuple, 2) the <i>executionFinished</i> method collects the result for one pattern, which is the aggregation of the <i>loopFinished</i> method results.</p>
	<p class="Para"><i>Reporting the result</i>. The result is generally reported in with the selected media, e.g. a file.</p>

	<p class="Para">For more complex reports, refer to the <i>org.eclipse.egf.emf.docgen.html</i> plug-in which examplifies the case of result in a file and a specific folder.</p>

	<br/>

	<h3 class="Head">4.6. Practice</h3>

	<p class="Para">1. Create a reporter Java class like this one:</p>
	<font color="777777"><pre>
	Package org.eclipse.egf.examples.uc1.reporter;

	import java.util.Map;

	import org.eclipse.egf.core.EGFCorePlugin;
	import org.eclipse.egf.model.pattern.PatternContext;
	import org.eclipse.egf.model.pattern.PatternExecutionReporter;

	public class MyReporter implements PatternExecutionReporter{

	@Override
	public void executionFinished(String output, PatternContext context) {
	// Message on the default console
	System.out.println("Result of pattern:\n"+output);
	// Message on the EGF console
	EGFCorePlugin.getDefault().logInfo("Result of pattern:\n"+output);
	}

	@Override
	public void loopFinished(String output, PatternContext context,
	Map<String, Object> parameterValues) {
	// TODO Auto-generated method stub
	}

	}
	</pre></font>

	<p class="Para">2. Complete the task with the reporter parameter:
	<ul CLASS="UnorderedList">
	<li CLASS="Item">Add a contract to the task created before</li>
	<li CLASS="Item">For Behaviour/Invoked Contract property, select the <i>pattern.execution.reporter</i> contract (removed before!)</li>
	<li CLASS="Item">Add the <i>Type Pattern Execution Reporter</i> and for value, select the pattern reporter class</li>
	</ul>
	</p>

	<h2 class="Head">5. Pattern translation</h2>
	<p class="Para">The pattern contents is translated into an executable form. This takes into account pattern inheritance and other pattern mechanisms not explained in this tutorial (e.g., pattern call). Next, at execution time, a pattern engine, specific to the pattern nature, executes a pattern.</p>
	<p class="Para">Patterns are translated on the fly. One case requires to manually force pattern rebuild: pattern inheritance. Indeed, children are not notified that a super-pattern in the hierarchy is update. To force this translation:</p>

	<ul CLASS="UnorderedList">
	<li CLASS="Item">On the <i>Pattern viewpoint</i> which contains all the pattern libraries - Command: <i>[Right-Click][Update generated elements]</i> </li>
	</ul>


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