---
layout: default
title: Languages
---


h2(#java). Java


h3. Compiling Java

The Java compiler looks for source files in the project's @src/main/java@ directory, and defaults to compiling them into the @target/classes@ directory. It looks for test cases in the project's @src/test/java@ and defaults to compile them into the @target/test/classes@ directory.

If you point the @compile@ task at any other source directory, it will use the Java compiler if any of these directories contains files with the extension @.java@.

When using the Java compiler, if you don't specify the packaging type, it defaults to JAR.  If you don't specify the test framework, it defaults to JUnit.

The Java compiler supports the following options:

|_. Option        |_. Usage |
| @:debug@        | Generates bytecode with debugging information.  You can also override this by setting the environment variable @debug@ to @off@. |
| @:deprecation@  | If true, shows deprecation messages.  False by default. |
| @:lint@         | Defaults to false.  Set this option to true to use all lint options, or specify a specific lint option (e.g. @:lint=>'cast'@). |
| @:other@        | Array of options passed to the compiler (e.g. @:other=>'-implicit:none'@). |
| @:source@       | Source code compatibility (e.g. '1.5'). |
| @:target@       | Bytecode compatibility (e.g. '1.4'). |
| @:warnings@     | Issue warnings when compiling.  True when running in verbose mode. |


h3.  Testing with Java

h4. JUnit

The default test framework for Java projects is "JUnit 4":http://www.junit.org.

When you use JUnit, the dependencies includes JUnit and "JMock":http://www.jmock.org, and Buildr picks up all test classes from the project by looking for classes that either subclass  @junit.framework.TestCase@, include methods annotated with @org.junit.Test@, or test suites annotated with @org.org.junit.runner.RunWith@.

The JUnit test framework supports the following options:

|_. Option        |_. Value |
| @:fork@         | VM forking, defaults to true. |
| @:clonevm@      | If true clone the VM each time it is forked. |
| @:properties@   | Hash of system properties available to the test case. |
| @:environment@  | Hash of environment variables available to the test case. |
| @:java_args@    | Arguments passed as is to the JVM. |

For example, to pass properties to the test case:

<notextile>
{% highlight ruby %}
test.using :properties=>{ :currency=>'USD' }
{% endhighlight %}
</notextile>

There are benefits to running test cases in separate VMs.  The default forking mode is @:once@, and you can change it by setting the @:fork@ option.

|_. :fork=> |_. Behavior |
| @:once@   | Create one VM to run all test classes in the project, separate VMs for each project. |
| @:each@   | Create one VM for each test case class.  Slow but provides the best isolation between test classes. |
| @false@   | Without forking, Buildr runs all test cases in a single VM.  This option runs fastest, but at the risk of running out of memory and causing test cases to interfere with each other. |

You can see your tests running in the console, and if any tests fail, Buildr will show a list of the failed test classes.  In addition, JUnit produces text and XML report files in the project's @reports/junit@ directory.  You can use that to get around too-much-stuff-in-my-console, or when using an automated test system.

In addition, you can get a consolidated XML or HTML report by running the @junit:report@ task.  For example:

<notextile>
{% highlight sh %}
$ buildr test junit:report test=all
$ firefox report/junit/html/index.html
{% endhighlight %}
</notextile>

The @junit:report@ task generates a report from all tests run so far.  If you run tests in a couple of projects, it will generate a report only for these two projects.  The example above runs tests in all the projects before generating the reports.

You can use the @build.yaml@ settings file to specify a particular version of JUnit or JMock.  For example, to force your build to use JUnit version 4.4 and JMock 2.0:

<notextile>
{% highlight yaml %}
junit: 4.4
jmock: 2.0
{% endhighlight %}
</notextile>


h4. TestNG

You can use "TestNG":http://testng.org instead of JUnit.  To select TestNG as the test framework, add this to your project:

<notextile>
{% highlight ruby %}
test.using :testng
{% endhighlight %}
</notextile>

Like all other options you can set with @test.using@, it affects the projects and all its sub-projects, so you only need to do this once at the top-most project to use TestNG throughout.  You can also mix TestNG and JUnit by setting different projects to use different frameworks, but you can't mix both frameworks in the same project.  (And yes, @test.using :junit@ will switch a project back to using JUnit)

TestNG works much like JUnit, it gets included in the dependency list along with JMock, Buildr picks test classes that contain methods annotated with  @org.testng.annotations.Test@, and generates test reports in the @reports/testng@ directory.  At the moment we don't have consolidated HTML reports for TestNG.

The TestNG test framework supports the following options:

|_. Option        |_. Value |
| @:properties@   | Hash of system properties available to the test case. |
| @:java_args@    | Arguments passed as is to the JVM. |

You can use the @build.yaml@ settings file to specify a particular version of TestNG, for example, to force your build to use TestNG 5.7:

<notextile>
{% highlight yaml %}
testng: 5.7
{% endhighlight %}
</notextile>


h4. JBehave 

"JBehave":http://jbehave.org/ is a pure Java BDD framework, stories and behaviour specifications are written in the Java language. 

To use JBehave in your project you can select it with @test.using :jbehave@.

This framework will search for the following patterns under your project:

<notextile>
{% highlight text %}
src/spec/java/**/*Behaviour.java
{% endhighlight %}
</notextile>

Supports the following options:

|_. Option        |_. Value |
| @:properties@   | Hash of system properties available to the test case. |
| @:java_args@    | Arguments passed as is to the JVM. |

You can use the @build.yaml@ settings file to specify a particular version of JBehave, for example, to force your build to use JBehave 1.0.1:

<notextile>
{% highlight yaml %}
jbehave: 1.0.1
{% endhighlight %}
</notextile>


h2(#scala). Scala

Before using Scala features, you must first set the @SCALA_HOME@ environment variable to point to the root of your Scala distribution.

On Windows:

<notextile>
{% highlight sh %}
> set SCALA_HOME=C:\Path\To\Scala-2.7.3
{% endhighlight %}
</notextile>

On Linux and other Unix variants,

<notextile>
{% highlight sh %}
> export SCALA_HOME=/path/to/scala-2.7.3
{% endhighlight %}
</notextile>

The @SCALA_HOME@ base directory should be such that Scala core libraries are located directly under the "lib" subdirectory, and Scala scripts are under the "bin" directory. This step is not necessary if you installed Scala using MacPorts (OS X).

You must also require the Scala compiler in your buildfile:

<notextile>
{% highlight ruby %}
require 'buildr/scala'
{% endhighlight %}
</notextile>

h3. Compiling Scala

The Scala compiler looks for source files in the project's @src/main/scala@  directory, and defaults to compiling them into the @target/classes@ directory.  It looks for test cases in the project's @src/test/scala@ and defaults to  compile them into the @target/test/classes@ directory.

Any Java source files found in the @src/main/java@ directory will be compiled using the Scala/Java joint compiler into the @target/classes@ directory.  Both the Java and the Scala sources are compiled with an inclusive classpath, meaning that you may have a Java class which depends upon a Scala class which depends upon a Java class, all within the same project.  The Java sources will be compiled with the same dependencies as the Scala sources with the addition of the @scala-library.jar@ file as required for Scala interop.

Note that you cannot use the Groovy *and* the Scala joint compilers in the same project.  If both are required, the Groovy joint compiler will take precedence.
+
If you point the @compile@ task at any other source directory, it will use the  Scala compiler if any of these directories contains files with the extension @.scala@.  The joint compilation of Java sources may only be pointed at an alternative directory using the feature to redefine the @_(:src, :main, :java)@ path.

When using the Scala compiler, if you don't specify the packaging type, it defaults to JAR.

The Scala compiler supports the following options:

|_. Option        |_. Usage |
| @:debug@        | Generates bytecode with debugging information.  You can also override this by setting the environment variable @debug@ to @off@. |
| @:deprecation@  | If true, shows deprecation messages.  False by default. |
| @:optimise@     | Generates faster bytecode by applying optimisations to the program. |
| @:other@        | Array of options passed to the compiler (e.g. @:other=>'-Xprint-types'@). |
| @:target@       | Bytecode compatibility (e.g. '1.4'). |
| @:warnings@     | Issue warnings when compiling.  True when running in verbose mode. |
| @:javac@        | A hash of options passed to the @javac@ compiler verbatim. |

h4. Fast Scala Compiler

You may use @fsc@, the Fast Scala Compiler, which submits compilation jobs to a  compilation daemon, by setting the environment variable @USE_FSC@ to @yes@. Note that @fsc@ _may_ cache class libraries -- don't forget to run @fsc -reset@ if  you upgrade a library.

h4. Rebuild detection

The Scala compiler task assumes that each @.scala@ source file generates a  corresponding @.class@ file under @target/classes@ (or @target/test/classses@  for tests). The source may generate more @.class@ files if it contains more than one class, object, trait or for anonymous functions and closures.

For example, @src/main/scala/com/example/MyClass.scala@ should generate at least @target/classes/com/example/MyClass.class@. If that it not the case, Buildr will always recompile your sources because it will assume this is a new source file that has never been compiled before.

h3. Testing with Scala

Buildr supports two main Scala testing frameworks:   "ScalaTest":http://www.artima.com/scalatest and  "Specs":http://code.google.com/p/specs/.  "ScalaCheck":http://code.google.com/p/scalacheck/ is also supported within the confines of either of these two frameworks.  Thus, your Specs may use ScalaCheck properties, as may your ScalaTest suites.

<notextile>
{% highlight ruby %}
test.using(:scalatest)
{% endhighlight %}
</notextile>

h4. ScalaTest

ScalaTest support is activated automatically when there are any @.scala@ source files contained in the @src/test/scala@ directory.  If you are not using this directory convention, you may force the test framework by using the @test.using :scalatest@ directive.

Buildr automatically detects and runs tests that extend the @org.scalatest.Suite@ interface.

A very simplistic test class might look like,

<notextile>
{% highlight scala %}
class MySuite extends org.scalatest.FunSuite {
  test("addition") {
    val sum = 1 + 1
    assert(sum === 2)
  }
}
{% endhighlight %}
</notextile>

You can also pass properties to your tests by doing @test.using :properties => { 'name'=>'value' }@, and by overriding the @Suite.runTests@ method in a manner similar to:

<notextile>
{% highlight scala %}
import org.scalatest._

class PropertyTestSuite extends FunSuite {
  var properties = Map[String, Any]()
  
  test("testProperty") {
    assert(properties("name") === "value")
  }

  protected override def runTests(testName: Option[String], 
    reporter: Reporter, stopper: Stopper, includes: Set[String], 
    excludes: Set[String], properties: Map[String, Any])
  {
    this.properties = properties;                              
    super.runTests(testName, reporter, stopper, 
                   includes, excludes, properties)
  }
}
{% endhighlight %}
</notextile>

h4. Specs

Specs is automatically selected whenever there are @.scala@ source files under the @src/spec/scala@ directory.  It is also possible to force selection of the test framework by using the @test.using :specs@ directive.  This can sometimes be useful when Scala sources may be found in *both* @src/test/scala@ and @src/spec/scala@.  Normally in such cases, ScalaTest will have selection precedence, meaning that in case of a conflict between it and Specs, ScalaTest will be chosen.

Any objects which extend the @org.specs.Specification@ superclass will be automatically detected and run.  Note that any *classes* which extend @Specification@ will also be invoked.  As such classes will not have a @main@ method, such an invocation will raise an error.

A simple specification might look like this:

<notextile>
{% highlight scala %}
import org.specs._
import org.specs.runner._

object StringSpecs extends Specification {
  "empty string" should {
    "have a zero length" in {
      ("".length) mustEqual(0)
    }
  }
}
{% endhighlight %}
</notextile>

h4. ScalaCheck

You may use ScalaCheck inside ScalaTest- and Specs-inherited classes.  Here is an example illustrating checks inside a ScalaTest suite,

<notextile>
{% highlight scala %}
import org.scalatest.prop.PropSuite
import org.scalacheck.Arbitrary._
import org.scalacheck.Prop._

class MySuite extends PropSuite {

  test("list concatenation") {
    val x = List(1, 2, 3)
    val y = List(4, 5, 6)
    assert(x ::: y === List(1, 2, 3, 4, 5, 6))
    check((a: List[Int], b: List[Int]) => a.size + b.size == (a ::: b).size)
  }

  test(
    "list concatenation using a test method",
    (a: List[Int], b: List[Int]) => a.size + b.size == (a ::: b).size
  )
}
{% endhighlight %}
</notextile>


h2(#groovy). Groovy

h3. Compiling Groovy

Before using the Groovy compiler, you must first require it on your buildfile:

<notextile>
{% highlight ruby %}
require 'buildr/java/groovyc'
{% endhighlight %}
</notextile>

Once loaded, the groovyc compiler will be automatically selected if any .groovy source files are found under @src/main/groovy@ directory, compiling them by default into the @target/classes@ directory.

If the project has java sources in @src/main/java@ they will get compiled using the groovyc joint compiler.

Sources found in @src/test/groovy@ are compiled into the @target/test/classes@.

If you don't specify the packaging type, it defaults to JAR.

The Groovy compiler supports the following options:

|_. Option        |_. Usage |
| @encoding@          | Encoding of source files. |
| @verbose@           | Asks the compiler for verbose output, true when running in verbose mode. |
| @fork@              | Whether to execute groovyc using a spawned instance of the JVM.  Defaults to no. |
| @memoryInitialSize@ | The initial size of the memory for the underlying VM, if using fork mode, ignored otherwise.  Defaults to the standard VM memory setting. (Examples: @83886080@, @81920k@, or @80m@) |
| @memoryMaximumSize@ | The maximum size of the memory for the underlying VM, if using fork mode, ignored otherwise.  Defaults to the standard VM memory setting. (Examples: @83886080@, @81920k@, or @80m@) |
| @listfiles@         | Indicates whether the source files to be compiled will be listed.  Defaults to no. |
| @stacktrace@        | If true each compile error message will contain a stacktrace. |
| @warnings@          | Issue warnings when compiling.  True when running in verbose mode. |
| @debug@             | Generates bytecode with debugging information.  Set from the debug environment variable/global option. |
| @deprecation@       | If true, shows deprecation messages.  False by default. |
| @optimise@          | Generates faster bytecode by applying optimisations to the program. |
| @source@            | Source code compatibility. |
| @target@            | Bytecode compatibility. |
| @javac@             | Hash of options passed to the ant javac task. |


h3. Testing with Groovy

h4. EasyB

"EasyB":http://www.easyb.org/ is a BDD framework using "Groovy":http://groovy.codehaus.org/. 

Specifications are written in the Groovy language, of course you get seamless Java integration as with all things groovy. 

To use this framework in your project you can select it with @test.using :easyb@.

This framework will search for the following patterns under your project:

<notextile>
{% highlight text %}
src/spec/groovy/**/*Behavior.groovy
src/spec/groovy/**/*Story.groovy
{% endhighlight %}
</notextile>

Supports the following options:

|_. Option        |_. Value |
| @:properties@   | Hash of system properties available to the test case. |
| @:java_args@    | Arguments passed as is to the JVM. |
| @:format@       | Report format, either @:txt@ or @:xml@ |


h2(#ruby).  Ruby

h3.  Testing with Ruby

Buildr provides integration with some ruby testing frameworks, allowing you to test your Java code with state of the art tools.

Testing code is written in "Ruby":http://www.ruby-lang.org/en/ language, and is run by using "JRuby":http://jruby.codehaus.org/. That means you have access to all your Java classes and any Java or Ruby tool out there.

Because of the use of JRuby, you will notice that running ruby tests is faster when running Buildr on JRuby, as in this case there's no need to run another JVM.

p(tip). When not running on JRuby, Buildr will use the @JRUBY_HOME@ environment variable to find the JRuby installation directory.  If no @JRUBY_HOME@ is set or it points to an empty directory, Buildr will prompt you to either install JRuby manually or let it  extract it for you.

You can use the @build.yaml@ settings file to specify a particular version of JRuby (defaults to @1.1.4@).  For example:

<notextile>
{% highlight yaml %}
jruby: 1.1.3
{% endhighlight %}
</notextile>

h4.  RSpec

"RSpec":http://rspec.info/ is the de-facto BDD framework for ruby. It's the framework used to test Buildr itself. 

To use this framework in your project you can select it with @test.using :rspec@.

This framework will search for the following patterns under your project:

<notextile>
{% highlight text %}
src/spec/ruby/**/*_spec.rb
{% endhighlight %}
</notextile>

Supports the following options:

|_. Option        |_. Value |
| @:gems@         | Hash of gems needed before running the tests. Keys are gem names, values are the required gem version. An example use of this option would be to require the ci_reporter gem to generate xml reports |
| @:requires@     | Array of ruby files to require before running the specs |
| @:format@       | Array of valid RSpec @--format@ option values. Defaults to html report on the @reports@ directory and text progress |
| @:output@       | File path to output dump. @false@ to supress output |
| @:fork@         | Run the tests on a new java vm. (enabled unless running on JRuby) |
| @:properties@   | Hash of system properties available to the test case. |
| @:java_args@    | Arguments passed as is to the JVM. (only when fork is enabled) |

h4.  JtestR

"JtestR":http://jtestr.codehaus.org is a tool that makes it easier to test Java code with state of the art Ruby tools. Using JtestR you can describe your application behaviour using many testing frameworks at the same time.

To use this framework in your project you can select it with @test.using :jtestr@.

You can use the @build.yaml@ settings file to specify a particular version of JtestR (defaults to @0.3.1@).  For example:

<notextile>
{% highlight yaml %}
jtestr: 0.3.1
{% endhighlight %}
</notextile>

To customize TestNG/JUnit versions refer to their respective section.

When selected, Buildr will configure JtestR to use your project/testing classpath and will search for the following test patterns for each framework supported by JtestR:

|_. Framework                    |_. Patterns |
| "RSpec":http://rspec.info      | Files in @src/spec/ruby@ ending with @*_spec.rb@ or @*_story.rb@ |
| "TestUnit":http://ruby-doc.org/stdlib/libdoc/test/unit/rdoc/classes/Test/Unit.html | Files in @src/spec/ruby@ ending with @*_test.rb@, @*Test.rb@ |
| "Expectations":http://expectations.rubyforge.org/ | Files in @src/spec/ruby@ ending with @*_expect.rb@ |
| "JUnit":http://www.junit.org   | Classes from @src/test/java@ that either subclass @junit.framework.TestCase@, include methods annotated with @org.junit.Test@, or test suites annotated with @org.org.junit.runner.RunWith@. |
| "TestNG":http://testng.org     | Classes from @src/test/java@ annotated with  @org.testng.annotations.Test@ |

If you create a @src/spec/ruby/jtestr_config.rb@ file, it will be loaded by JtestR, just after being configured by Buildr, this way you can configure as described on "JtestR guide":http://jtestr.codehaus.org/Configuration.

p(tip). If you have a @jtestr_config.rb@ file, don't set @JtestR::result_handler@. Buildr uses its (@RSpecResultHandler@)  so that it can know which tests succeeded/failed, this handler is capable of using RSpec formatter classes, so that you can obtain an html report or use a custom rspec formatter with @JtestR@. See the @format@ option.

Supports the following options:

|_. Option        |_. Value |
| @:config@       | The JtestR config file to be loaded after being configured by Buildr. Defaults to @src/spec/ruby/jtestr_config.rb@. |
| @:gems@         | Hash of gems needed before running the tests. Keys are gem names, values are the required gem version. An example use of this option would be to require the ci_reporter gem to generate xml reports |
| @:requires@     | Array of ruby files to require before running the specs |
| @:format@       | Array of valid RSpec @--format@ option values. Defaults to html report on the @reports@ directory and text progress |
| @:output@       | File path to output dump. @false@ to supress output |
| @:fork@         | Run the tests on a new java vm. (enabled unless running on JRuby) |
| @:properties@   | Hash of system properties available to the test case. (only when fork is enabled) |
| @:java_args@    | Arguments passed as is to the JVM. (only when fork is enabled) |