FSTComposer: Software Composition based on Feature Structure Trees and Superimposition</title> <link href="ar.css" rel="stylesheet" type="text/css" /> </head> <body> <h1 align="center"><em>FSTComposer</em>: Software Composition based on Feature Structure Trees and Superimposition</h1> <br> <h3 align="center">Note: <em>FSTComposer</em> has been integrated recently into the <a href="http://www.infosun.fim.uni-passau.de/cl/staff/apel/FH/" target="_blank"><em>FeatureHouse</em></a> tool chain</h3> <br> <h5 align="center">Latest Version 0.2 (Dec 05, 2007)</h5> <div id="nav"> <div class="link"><a href="#intro">Introduction</a></div> <div class="link"><a href="#howto">Howto</a></div> <div class="link"><a href="#examples">Examples</a></div> <div class="link"><a href="#modifications">Modifications</a></div> <div class="link"><a href="#download">Downloads</a></div> <div class="link"><a href="#contact">Contact</a></div> <p align="center"><br/> <br> <A HREF="http://www.uni-passau.de/index.php?id=6&L=1"><IMG ALT="UniLogo" WIDTH="216" HEIGHT="57" BORDER="0" SRC="http://www.uni-passau.de/icons/unilogo/u0256.gif"></A> <br><br> <A HREF="http://www.fim.uni-passau.de/en"><IMG ALT="FIM" WIDTH="70" HEIGHT="70" BORDER="0" SRC="./images/fmilogo.jpg"></A> <br> <A HREF="http://www.fim.uni-passau.de/en"><IMG BORDER="0" SRC="./images/fim.jpg"></A> <br><br> <A HREF="http://www.infosun.fim.uni-passau.de/cl/index-e.html"><IMG ALT="Programming Group" WIDTH="80" HEIGHT="80" BORDER="0" SRC="./images/cllogo.jpg"></A> <br> <A HREF="http://www.infosun.fim.uni-passau.de/cl/index-e.html"><IMG BORDER="0" SRC="./images/pg.jpg"></A>  </p> <br> <p align="center">Last updated 2007-12-05</p> </div> <div class="con"> <h2><a name="intro" id="introduction"></a>Introduction</h2> <p class="abstract"><em>FSTComposer</em> is a tool for composing software components based on their representation as <i>feature structure trees (FSTs)</i> and FST-based superimposition. <em>FSTComposer</em> implements the <a href="http://www.cs.utexas.edu/users/schwartz/">AHEAD model</a> for software composition and program synthesis in a language-independent way. General information about FSTs and FST-based superimposition can be found in a conference paper <a href="http://www.infosun.fim.uni-passau.de/cl/staff/apel/publications/SC2008.pdf">(SC'08)</a> and in two technical reports <a href="http://www.infosun.fim.uni-passau.de/cl/staff/apel/publications/mip-0706.pdf">(MIP-0706)</a> and <a href="http://www.infosun.fim.uni-passau.de/cl/staff/apel/publications/mip-0712.pdf">(MIP-0712)</a> of Department of Informatics and Mathematics of the University of Passau. </p> <p class="abstract"> Currently, <em>FSTComposer</em> provides a Java parser and an XML parser that generate FSTs on the basis of source code. The result of a composition is a superimposed FST that can be displayed in several ways or written out as a composed program. The composition is handeled independently of a particular language. <em>FSTComposer</em> provides information about the input components and the composed program in several representations (XML, FST, algebraic expression, GUI). The <a href="#examples">examples section</a> contains some code snippets taken from features written in Java and XML. </p> <h2><a name="howto"></a>Howto</h2> <p> After <a href="deploy/FSTComposer-0.2.zip">downloading</a> and unzipping the archive, <em>FSTComposer</em> is ready to use. The command below invokes <em>FSTComposer</em> in the directory in which it was installed: <div class="code"> java -jar FSTComposer-0.2.jar --expression <expression file> </div> <br> The option <code>--expression <expression file></code> specifies the location of a file that lists the names of the components to compose. Note that the components are represented by file system directories that have the same name (a.k.a. <i><a href="ftp://ftp.cs.utexas.edu/pub/predator/TSE-AHEAD.pdf">containment hierarchies</a></i>). </p> <p> Several further command line options specify what <em>FSTComposer</em> is going to do with the input components: <div class="code"> java ... --base-directory <component search path></code> --ahead --write --gui --xml --fst --sum --resolve-references </div> <ul> <li><code>--help</code> : This option prints some information about the options to the standard output.</li> <li><code>--base-directory <component search path></code> : This option specifies where the components are located (if not in the same directory than the expression file). Note that the path has to end with a slash (<code>examples/GraphJava/</code> instead of <code>examples/GraphJava</code>) <li><code>--ahead</code> : This option is necessary to parse Jak/AHEAD source code (as opposed to Java source code).</li> <li><code>--write</code> : This option writes the composed program to a directory that is in the component source directory and whose name is the name of the input expression file. <li><code>--gui</code> : This option displays the input components in a GUI. When the option <code>--resolve-references</code> is used, the dependencies between features/components are visualized.</li> <li><code>--xml</code> : This option prints the structure of the input components as XML string to the standard output.</li> <li><code>--fst</code> : This option prints the FST representation of the composed program to the standard output.</li> <li><code>--sum</code> : This option prints the FST representation of the composed program as a sum of <a href="http://www.infosun.fim.uni-passau.de/cl/staff/apel/publications/mip-0706.pdf">algebraic terms</a> to the standard output.</li> <li><code>--resolve-references</code> : This option analyzes several kinds of dependencies between the input features/components. The references appear in the XML output and the GUI.</li> </ul> </p> <p> The below picture shows a screenshot of <em>FSTComposer</em> in GUI mode visualizing the interactions between the features/components of the GPL example. </p> <IMG BORDER="0" SRC="./images/FSTComposer.jpg"> <h2><a name="examples"></a>Examples</h2> <ul> <li><b>Java</b> <ul> <li> A <a href="./listings/StackBase.txt" target="_blank">Java class implementing a stack</a> and an <a href="./listings/StackExt.txt" target="_blank">extension that the disallows a stack underflow</a>. Both are composed via superimposition. </ul> <li><b>XML</b></li> <ul> <li> An <a href="./listings/GPLDocBase.txt" target="_blank">XHTML documentation of the GPL case study</a> (included in the <a href="#download">FSTComposer distribution</a>) and an <a href="./listings/GPLDocExt.txt" target="_blank">extension that adds information about a new algorithm (cycle checking)</a>. Both are composed via superimposition. </ul> </ul> <h2><a name="modifications"></a>Modifications</h2> <p>A <i>modification</i> is an additional/alternative mechanism to implement features. It is a tree walk consisting of a <i>query</i> that specifies which nodes of a target FST are modified and a <i>definition of change</i> that specifies how selected nodes are changed. Details about modifications can be found in a <a href="http://www.infosun.fim.uni-passau.de/cl/staff/apel/publications/mip-0706.pdf">technical report</a>.</p> <p>Modifications are expressed as special XML files with the extension <code>.mod</code>. <em>FSTComposer</em> automatically recongnizes modifications that are located in a feature's directory and applies them to the program. For example, the below modification injects a field <code>count</code> into the class <code>Stack</code>:</p> <div class="code"> <?xml version="1.0" encoding="UTF-8"?><br> <tns:ModificationModel xmlns:tns="http://www.scharinger.de/FOPSchemata" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.scharinger.de/FOPSchemataFOPModification.xsd"><br> <tns:Modification FeatureName="StackTrace"><br> <tns:Query><br> <tns:QueryFST><br> <tns:Compound ID="f1" JavaType="Feature" Name=".*" xsi:type="tns:FeatureCompoundType"><br> <tns:Compound ID="p1" JavaType="Package" Name=".*" xsi:type="tns:PackageCompoundType"><br> <tns:Compound ID="c1" JavaType="Class" Name="Stack" xsi:type="tns:ClassCompoundType"><br> </tns:Compound><br> </tns:Compound><br> </tns:Compound><br> </tns:QueryFST><br> </tns:Query><br> <tns:Change><br> <tns:ChangeFST><br> <tns:Atomic ID="fe1" JavaType="Field" Name="count" xsi:type="tns:FieldAtomicType"><br> <tns:ModifierList><br> <tns:Modifier>public</tns:Modifier><br> </tns:ModifierList><br> <tns:Type>int</tns:Type><br> <tns:Content>= 0;</tns:Content><br> </tns:Atomic><br> </tns:ChangeFST><br> </tns:Change><br> </tns:Modification><br> </tns:ModificationModel> </div> <p>Note that the feature and package names contain regular expressions. The reason is that every class <code>Stack</code> is supposed to be modified regardless in which feature and package it is located. Further examples are a <a href="./listings/vertex_accesses.mod" target="_blank">modification for counting the accesses to <code>Vertex</code> objects</a> and a <a href="./listings/node_state_writer.mod" target="_blank">modification for logging the state of <code>Node</code> objects</a>. The former is intended for the GPL case study and the latter for the Violet case study; both studies are included in the FSTComposer distribution. See also the StackJava example in the FSTComposer distribution (Version 0.2) for an example in action.</p> <h2><a name="download"></a>Download</h2> <ul> <li><b>Version 0.2</b> <ul> <li>Binaries and examples: <a href="deploy/FSTComposer-0.2.zip">FSTComposer-0.2.zip</a></li> <li>Sources: <a href="deploy/FSTComposer-src-0.2.zip">FSTComposer-src-0.2.zip</a></li> </ul> </li> <li><b>Version 0.1</b> <ul> <li>Binaries and examples: <a href="deploy/FSTComposer-0.1.zip">FSTComposer-0.1.zip</a></li> </ul> </li> </ul> <p>Beside the binaries, the archive contains six examples (GraphJak, GraphJava, GPL, GUIDSL, myVioletJava, StackJava). Every example contains at least one <code>.expression</code> file that lists the components that are analyzed and/or composed. All examples are written in Jak, except GraphJava. Note that for all examples written in Jak the command line option <code>--ahead</code> has to be specified.</p> <p>For example, in order to compose the GraphJak example invoke: <div class="code"> java -jar FSTComposer-0.2.jar --expression examples/GraphJak/CompGraph.expression --ahead --write </div> <br> In order to view the GraphJava example in the GUI with dependencies invoke: <div class="code"> java -jar FSTComposer-0.2.jar --expression examples/GraphJava/CompGraph.expression --gui --resolve-references </div> <p>Note that some examples (myVioletJava, StackJava, GPL) contain non-code artifacts such as XML documents. These documents are also composed via superimposition.</p> <p>The source code of <em>FSTComposer</em> can be requested from the developers per mail.</p> <h2><a name="contact" id="contact"></a>Contact</h2> <p><em>FSTComposer</em> was developed at the University of Passau, Germany. For information about the <em>FSTComposer</em> project, please contact the development team via <img src="images/mail.png" align="bottom" BORDER="0">. </p> <p>The <em>FSTComposer</em> project members: </p> <ul> <li>Sven Apel (University of Passau, Germany)</li> <li>Sebastian Scharinger (University of Passau, Germany)</li> </ul> </div> <div class="end"> </div> </body> </html>