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Scala Ant Tasks

Created by admin on 2008-07-04. Updated: 2009-11-30, 20:06

The Scala distribution contains several tasks for building software projects using Apache Ant, a Java-based build tool. The tasks described below require Apache Ant version 1.6 or newer.

The Scala tasks are: scalac, fsc and scaladoc

scalac

Description

Compiles a Scala source tree.

The source and destination directory will be recursively scanned for Scala source files to compile. Only Scala files that have no corresponding .class file or where the class file is older than the .scala file will be compiled.

Note: Ant uses only the names of the source and class files to find the classes that need a rebuild. It will not scan the source and therefore will have no knowledge about nested classes, classes that are named different from the source file, and so on.

It is possible to refine the set of files that are being compiled. This can be done with the includes, includesfile, excludes, and excludesfile attributes. With the includesor includesfile attribute, you specify the files you want to have included. Theexclude or excludesfile attribute is used to specify the files you want to have excluded. In both cases, the list of files can be specified by either the filename, relative to the directory(s) specified in the srcdir attribute or nested <src> element(s), or by using wildcard patterns. See the Ant documentation on directory-based tasks, for information on how the inclusion/exclusion of files works, and how to write wildcard patterns.

Parameters

AttributeDescriptionRequiredsrcdirLocation of the Scala files.Yes, unless nested<src>elements or srcref are present.srcrefLocation of the Scala files, given as a reference to a path defined elsewhere.Yes, unless nested<src>elements or srcdir are present.destdirLocation to store the class files.NoclasspathThe classpath to use.NoclasspathrefThe classpath to use, given as a reference to a path defined elsewhere.NosourcepathThe sourcepath to use; defaults to the value of the srcdir attribute (or nested<src> elements). To suppress the sourcepath switch, use sourcepath="".NosourcepathrefThe sourcepath to use, given as a reference to a path defined elsewhere.NobootclasspathLocation of bootstrap class files.NobootclasspathrefLocation of bootstrap class files, given as a reference to a path defined elsewhere.NoextdirsLocation of installed extensions.NoextdirsrefLocation of installed extensions, given as a reference to a path defined elsewhere.NotargetSpecifies which backend to use; defaults to jvm-1.4 (accepted values are:jvm-1.5, jvm-1.4, msil).NodeprecationIndicates whether source should be compiled with deprecation information; defaults to no (accepted values are: on, off,yes and no). 
Available since Scala version 2.3.NouncheckedIndicates whether source should be compiled with unchecked information; defaults to no (accepted values are: on, off, yesand no). 
Available since Scala version 2.3.NoencodingEncoding of source files.NologgingAsks the compiler for verbose output; defaults to none (accepted values are:none, verbose, and debug).NousepredefsAsks the compiler to use predefined values for compilation; defaults to yes.NoforceWhether to force the compilation of all files; possible values are false (only compile modified files), and true (always recompile all files); defaults tofalse.NoaddparamsSpecifies additional command line arguments to be passed to the Scala tool. 
The user may for example specify advanced options (eg. -Xresident) as well as private options (eg. -Ydebug) not available as Ant attributes.NofailonerrorIndicates whether compilation errors will fail the build; defaults to true. 
Available since Scala version 2.6.NoscalacdebuggingIf set to true, the scalac Ant taks will print the filenames being compiled, instead of only the number of files.NoassemnameThe assembly name. Only relevant if the target is "msil".NoassemrefsReferences to external assemblies. Only relevat if the target is "msil"No

Parameters specified as nested elements

This task forms an implicit FileSet and supports all attributes of <fileset> (dir becomes srcdir) as well as the nested<include>, <exclude> and <patternset> elements.

src, classpath, sourcepath, bootclasspath and extdirs

Scalac's srcdir, classpath, sourcepath, bootclasspath, and extdirs attributes are path-like structures and can also be set via nested <src>, <classpath>, <sourcepath>,<bootclasspath> and <extdirs> elements, respectively.

Requirements

• Ant 1.6 or higher
• Scala 2.2 or higher

Example

  <property    name="sources.dir"    value="${base.dir}/sources"     />  <property    name="build.dir"    value="${base.dir}/build"     />  <target name="init">    <property      name="scala-library.jar"      value="${scala.home}/lib/scala-library.jar"       />    <path id="build.classpath">      <pathelement location="${scala-library.jar}"   />      <!--<pathelement location="${your.path}"   />-->      <pathelement location="${build.dir}"   />    </path>    <taskdef resource="scala/tools/ant/antlib.xml">      <classpath>        <pathelement location="${scala.home}/lib/scala-compiler.jar"   />        <pathelement location="${scala-library.jar}"   />      </classpath>    </taskdef>  </target>

In the above target "init" the task taskdef defines the Scala ant tasks fsc, sbaz, scalac and scalascript.

  <target name="build" depends="init">    <mkdir dir="${build.dir}"   />    <scalac srcdir="${sources.dir}"            destdir="${build.dir}"            classpathref="build.classpath">      <include name="compile/**/*.scala"   />      <exclude name="forget/**/*.scala"   />    </scalac>  </target>

Compiles all Scala files in sources/compile/ (not in sources/forget) to build/ with given classpath. Files in sources/forget/will not necessarily be compiled, but might be as they are in the sourcepath. All modified files are re-compiled.

fsc (fast Scala compiler)

Description

Compiles a Scala source tree.

The fsc Ant task supports the same set of parameters as the scalac Ant task with the following additional parameters:

Parameters

AttributeDescriptionRequiredresetReset compile server caches.NoshutdownShutdown compile server.NoserverSpecify compile server host and port number. Usually this option is not needed. Note that the hostname must be for a host that shares the same filesystem.No

Requirements

• Ant 1.6 or higher
• Scala 2.2 or higher

scaladoc

Description

Generates the API documentation in HTML format for the given source files.

The scaladoc Ant task supports the same set of parameters as the scalac Ant task with the following additional parameters:

Parameters

AttributeDescriptionRequiredwindowtitleSpecify the text to appear in the window title.
Default value: "Scala 2".NodoctitleSpecify the text to appear in the main frame title.
Default value: "Scala 2<br />API Specification"No, HTML code is supported.stylesheetfileFile to change style of the generated documentation.
NB. The file name is system-dependent. 
Available since Scala version 2.5.NoheaderInclude header text for each page. 
Available since Scala version 2.5.No, HTML code is supported.footerInclude footer text for each page. 
Available since Scala version 2.5.No, HTML code is supported.topInclude top text for each page. 
Available since Scala version 2.5.No, HTML code is supported.bottomInclude bottom text for each page. 
Available since Scala version 2.5.No, HTML code is supported.

Requirements

• Ant 1.6 or higher
• Scala 2.2 or higher

Example

  <target name="docs" depends="init">    <mkdir dir="${docs.dir}"   />    <scaladoc      srcdir="${sources.dir}"      destdir="${docs.dir}"      deprecation="yes" unchecked="yes"      windowtitle="liftweb Library Documentation"      doctitle="&lt;div&gt;liftweb 0.1.0&lt;/div&gt;"      classpathref="build.classpath">        <include name="compile/**/*.scala"   />    </scaladoc>  </target>

java (Ant core task)

Description

Executes a Java class within the running (Ant) VM or forks another VM if specified.

The task java belongs the core tasks of the Ant distribution.

Note: The Scala library scala-library.jar must be present in the Java class path. The actors and dbc libraries are available as separate JAR files: scala-actors.jarand scala-dbc.jar.

Example

  <target name="run" depends="build">    <java classname="examples.sort"          classpathref="build.classpath">    </java>  </target>