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Section: File Formats (5) Updated: June 2005
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build.xml - configuration file used by ant to build projects



The file build.xml is the default configuration file used by ant to determine target to build for a specific project. It can be considered the ant equivalent of Makefile.

The format of ant is XML and for each project a seperate file is constructed. The buildfile consists of one or more tasks. An example is given below.

<project default="compile">
  <target name="compile">
    <javac srcdir="src"/>


This example has one target and it is defaulted. The target itself consists of one task javac which compiles the files in the src directory.



Targets can depend on other targets. These dependencies are given by the depends attribute of the <target> element.



A task is a piece of code that is executed. Ant recognizes built-in task, optional tasks, but one can also write new tasks.

Built-in tasks

The built-in tasks are: Ant, AntCall, AntStructure, Apply, Available, Basename, BuildNumber, BUnzip2, BZip2, Checksum, Chmod, Concat, Condition, Copy, Cvs, Delete, Deltree, Dirname, Ear, Echo, Exec, Fail, Filter, FixCRLF, GenKey, Get, GUnzip, GZip, Import, Input, Jar, Java, Javac, Javadoc, Length, LoadFile, LoadProperties, Mail, Mkdir, Move, Nice, Parallel, Patch, PathConvert, Property, Record, Replace, Rmic, Sequential, SignJar, Sleep, Sql, Style, Subant, Sync, Tar, Taskdef, Tempfile, Touch, TStamp, Typedef, Unjar, Untar, Unwar, Unzip, Uptodate, Waitfor, War, WhichResource, XmlProperty, Xslt, Zip

Executes a Java class within the running (Ant) VM or forks another VM if specified. Below are some of the attibutes to the <java> element:

classname (required) the Java class to execute

fork if enabled triggers the class execution in another VM (disabled by default)

jvm the command used to invoke the Java Virtual Machine, default is java. The command is resolved by java.lang.Runtime.exec(). Ignored if fork is disabled.

Other arguments are classpath, classpathref, maxmemory, failonerror, dir and output.

Compiles a source tree within the running (Ant) VM.

srcdir (required) location of the java files

destdir location to store the class files

debug indicates whether source should be compiled with debug information; defaults to off

optimize indicates whether source should be compiled with optimization; defaults to off

target generate class files for specific VM version (e.g., 1.1 or 1.2).

includes comma-separated list of patterns of files that must be included; all files are included when omitted

excludes comma-separated list of patterns of files that must be excluded; no files (except default excludes) are excluded when omitted.

defaultexcludes indicates whether default excludes should be used (yes | no); default excludes are used when omitted.

Other arguments are includesfile, excludesfile, classpath, bootclasspath, classpathref, bootclasspathref, extdirs, encoding, deprecation, verbose, includeAntRuntime, includeJavaRuntime and failonerror.



A project can have a set of properties, which consist of a name value combination. Within tasks they can be used by placing them between "${" and "}", as in "${builddir}/classes".

Built-in Properties

Ant provides access to all system properties as if they had been defined using a <property> task. For example, ${} expands to the name of the operating system.

the absolute path of the project's basedir (as set with the basedir attribute of <project>).
the absolute path of the buildfile.
the version of Ant.
the name of the project that is currently executing; it is set in the name attribute of <project>.
the JVM version Ant detected; currently it can hold the values "1.1", "1.2" and "1.3".



The classpath can be set by using the <classpath> element:

  <pathelement path="${classpath}"/>
  <pathelement location="lib/helper.jar"/>
  <fileset dir="lib">
    <include name="**/*.jar"/>
  </fileset>  </classpath>






This manpage is made by Egon Willighagen <> and based on the Ant Manual <>.




This document was created by man2html, using the manual pages.
Time: 21:59:56 GMT, April 16, 2011