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'''The MDT-OCLTools Project has closed.  This page has been locked and is for Archival purposes only.'''

OCL Tools is a recently added component to the 
[http://www.eclipse.org/modeling/mdt Model Development Tools (MDT)] Project 
aiming at providing first-class support to modelers
working with specifications containing expressions written in OCL, the
Object Constraint Language. Such support
includes editing, refactoring, code generation, execution, and
interactive debugging of the OCL constraints given for some underlying
(Ecore or UML2) class model. The functionality of OCL Tools builds upon
the MDT OCL component, and has been seeded with two initial
contributions:

<ul>
	<li>an OCL -> Java compiler, that as of now takes as input an
	<tt>.ecore</tt> and a textual file containing OCL constraints (handling UML2 is
	in the ToDo list). This compiler extends EMF code generation, producing
	Java 5 source code with side-effects-free methods for the given OCL
	invariants, pre- and postconditions, and derived attributes and
	operations.</li>

	<li>an OCL text editor, supporting usability features such as
	AutoCompletion, navigation by means of hyperlinks, structured views
	(for the outline of a document and for the Abstract Syntax Tree of an
	OCL constraint), among others. Although MDT OCL itself is completely
	fluent in both Ecore and UML2, only the Ecore binding is supported by
	the OCL text editor at this time.</li>
</ul>

A longer intro to OCL Tools can be found in the draft article being reviewed for publication at: 
https://bugs.eclipse.org/bugs/show_bug.cgi?id=204701


== OCL Compiler == 

=== What it does ===

In a nutshell, the compiler translates expressions like that in
Listing 1 into what is shown in Listing 2:

<table border="0" cellpadding="4">
<tr>
<td>
<pre class="snippet">
context LoyaltyAccount
	inv invariant_points :
		self . points > 0
		implies self.transactions->exists ( t | t.points > 0 )
</pre>
</td>
</tr>
<caption align="bottom"><b>Listing 1 </b>An OCL Invariant</caption>
</table>
<table border="0" cellpadding="4">
<tr>
<td>
<pre class="snippet">
public boolean invariant_points () {
	Boolean implies1 = ( this . getPoints () > 0);
	if (!( implies1 )) {
		implies1 = Boolean . TRUE ;
	} else {
		Boolean exists2 = false ;
		for ( RandL . Transaction t :
		org.eclipse.ocl.util.CollectionUtil.asSet ( this . getTransactions ())) {
				if (!exists2 ) {
					exists2 = (t.getPoints () > 0);
				}
		}
		implies1 = exists2 ;
	}
	return implies1 ;
}
</pre>
</td>
</tr>
<caption align="bottom"><b>Listing 2 </b><tt>LoyaltyAccount</tt>'s <tt>invariant_points</tt> translated into Java</caption>
</table>




=== How to use it ===

<b>Step 1</b>: Prepare an <code>.ocl</code> file

[[Image:OCLTools_oclcompiler01.PNG|<b>Figure 1(a)</b> Start situation]]


<b>Step 2</b>: Invoke the compiler

[[Image:OCLTools_oclcompiler02.PNG|<b>Figure 1(b)</b> Invoking the compiler by right-clicking on the <code>.ecore</code> file]]

The compiler works ...

[[Image:OCLTools_oclcompiler03.PNG|<b>Figure 1(c)</b> The compiler works ...]]

<b>Step 3</b>: Java code is ready

[[Image:OCLTools_oclcompiler04.PNG|<b>Figure 1(d)</b> End result]]


=== How to install ===

OCL Tools is known to apply to the following versions:

<ul>

<li>
  [http://download.eclipse.org/eclipse/downloads/drops/R-3.3.1.1-200710231652/index.php Eclipse Classic 3.3]
</li>

<li>
  [http://archive.eclipse.org/modeling/emf/emf/downloads/drops/2.3.1/R200709252135/ EMF SDK 2.3.1]
</li>

<li>
  [http://archive.eclipse.org/modeling/mdt/ocl/downloads/drops/1.1.1/R200709121604/ OCL SDK 1.1.1] 
</li>
</ul>


== User Community ==

In order to foster the evolution of OCL Tools, user input is important. If you're using OCL Tools, please add yourself to this list, as a first step towards building a community. Literature reflecting best-practices is also welcome (and somewhat scarce as of now :-) 

<table align="center" border="1" cellpadding="2">

<tr>
<td>Fernando Silva Parreiras
</td>
<td>[http://www.fernando.parreiras.nom.br/ http://www.fernando.parreiras.nom.br/]
</td>
</tr>

<tr>
<td>Abdelouahed Gherbi 
</td>
<td>[http://www.informatik.uni-trier.de/~ley/db/indices/a-tree/g/Gherbi:Abdelouahed.html http://www.informatik.uni-trier.de/~ley/db/indices/a-tree/g/Gherbi:Abdelouahed.html]
</td>
</tr>

</table>


== Best Practices ==

<ul>

<li>Improving the Interoperability of Automotive Tools by Raising the Abstraction from Legacy XML Formats to Standardized Metamodels
<br/>
[http://www.springerlink.com/index/l7005436w7j5v14q.pdf http://www.springerlink.com/index/l7005436w7j5v14q.pdf]
</li>

<li>&Uuml;berpr&uuml;fung Syntaktischer Robustheit von Statecharts auf der Basis von OCL
<br/>
[http://rtsys.informatik.uni-kiel.de/~biblio/downloads/theses/kbe-dt.pdf http://rtsys.informatik.uni-kiel.de/~biblio/downloads/theses/kbe-dt.pdf]
</li>

</ul>

== FAQ: Frequently Anticipated Questions ==

<b>I invoke the compiler but no code gets generated. What can I do?</b>

The OCL compiler should generate code when invoked with both 

<pre>
    <yourFileName>.ecore
    <yourFileName>.ocl
</pre>

on the same folder. Moreover, the .ocl file should be of the form 

<pre>
    package <packageName>
    
    context <myClass>
    ...
    
    endpackage 
</pre>

There is guidance about that in the exampled co-delivered with the source code, in plugin 
<pre>de.tuhh.sts.ocl.example.royalandloyal</pre>

If all else fails, actually the shortest way to see why the compiled Java does not end up in .java files is to place a breakpoint at method 

<pre>
    public void compile(IFile ecoreFile, IProgressMonitor monitor)
</pre>

in class <code>OCLCompiler</code> in plugin <code>de.tuhh.sts.ocl.compiler.emf.compiler</code>

Actually, that's where the action is. The rest is just glue code so that those generated methods bodies are woven as part of EMF code generation (which generates method signatures, class skeletons, etc.) 

The JET templates co-delivered with the OCL compiler override some hooks in the JET templates of EMF CodeGen, and when those templates change the hooks might not be there any more. For a discussion of this and what to do about it, take a look at: 

[http://dev.eclipse.org/newslists/news.eclipse.modeling.mdt.ocl/msg01379.html http://dev.eclipse.org/newslists/news.eclipse.modeling.mdt.ocl/msg01379.html]

== OCL Text Editor == 

The big picture of the editor is: 

[[Image:OCLTools_oclEditor_screenshots.png]]

=== Features supported ===

Among others, it supports the following: 

==== Syntax highlighting ==== 

==== AutoEdit 1 ==== 

Auto-completion of closing brace

==== AutoEdit 2 ==== 

Upon typing a colon <code>:</code> and pressing Enter. A new indented line will be added, letting the 
cursor ready for typing the body of the OCL expression.

==== Bracket matching ==== 

==== Content Assist ==== 

[[Image:OCLTools_content_assist.png]]

==== Current line highlighting and Show range indicator ==== 

==== Text Folding ==== 

==== Templates, customizable through Preference pages ==== 

[[Image:OCLTools_editor_preference_page.png]]


==== Problem and Warning markers, "red squigglies" ==== 

[[Image:OCLTools_problem_markers.png]]


==== Outline view ==== 

==== OCL AST View ==== 

[[Image:OCLTools_oclASTView.png]]

== Related Links ==

* [http://www.eclipse.org/modeling Modeling Project] [http://wiki.eclipse.org/index.php/Category:Modeling Category] [[Modeling_Project|Wiki]] 
** [http://www.eclipse.org/modeling/mdt Model Development Tools] [http://wiki.eclipse.org/index.php/Category:MDT Category] [[MDT|Wiki]]

[[Category:Modeling]]
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