# Running Apache Ant

# Running Ant

## Command Line

If you've installed Ant as described in the Installing Ant section, running Ant from the command-line is simple: just type `ant`.

When no arguments are specified, Ant looks for a `build.xml` file in the current directory and, if found, uses that file as the buildfile and runs the "default" target. If you use the `-find` option, Ant will search for a buildfile first in the current directory, then in the parent directory, and so on, until either a buildfile is found or the root of the filesystem has been reached. To make Ant use a buildfile other than `build.xml`, use the command-line option `-buildfile file`, where file is the name of the buildfile you want to use.

You can also set properties that override properties specified in the buildfile (see the property task). This can be done with the `-Dproperty=value` option, where property is the name of the property, and value is the value for that property. This can also be used to pass in the value of environment variables. Just pass `-DMYVAR=%MYVAR%` (Windows) or `-DMYVAR=$MYVAR` (Unix) to Ant - you can then access these variables inside your buildfile as `${MYVAR}`. You can also access environment variables using the property task.

Options that affect the amount of logging output by Ant are: `-quiet`, which instructs Ant to print less information on the console when running; `-verbose`, which causes Ant to print additional information to the console; and `-debug`, which causes Ant to print considerably more additional information.

It is also possible to specify one or more targets that should be executed. When omitted, the target that is specified in the `default` attribute of the `project` tag is used.

The `-projecthelp` option prints out a list of the buildfile's targets, along with the text in the `description` attribute of the target, if one was specified, followed by a list of those targets without one.

### Command-line Options Summary

    ant [options] [target [target2 [target3] ...]]
    Options:
      -help                  print this message
      -projecthelp           print project help information
      -version               print the version information and exit
      -quiet                 be extra quiet
      -verbose               be extra verbose
      -debug                 print debugging information
      -emacs                 produce logging information without adornments
      -logfile <file>        use given file for log
      -logger <classname>    the class which is to perform logging
      -listener <classname>  add an instance of class as a project listener
      -buildfile <file>      use given buildfile
      -D<property>=<value>   use value for given property
      -propertyfile <name>   load all properties from file with -D
                             properties taking precedence
      -find <file>           search for buildfile towards the root of the
                             filesystem and use it

For more information about `-logger` and `-listener` see the section Loggers & Listeners

### Examples

>     ant

runs Ant using the `build.xml` file in the current directory, on the default target.

>     ant -buildfile test.xml

runs Ant using the `test.xml` file in the current directory, on the default target.

>     ant -buildfile test.xml dist

runs Ant using the `test.xml` file in the current directory, on a target called `dist`.

>     ant -buildfile test.xml -Dbuild=build/classes dist

runs Ant using the `test.xml` file in the current directory, on a target called `dist`, setting the `build` property to the value `build/classes`.

### Files

The Ant wrapper script for Unix will source (read and evaluate) the file `~/.antrc` before it does anything - the Windows batch file invokes `%HOME%\antrc_pre.bat` at the start and `%HOME%\antrc_post.bat` at the end. You can use these files to set/unset environment variables that should only be visible during the execution of Ant. See the next section for example.

### Environment Variables

The wrapper scripts use the following environment variables (if set):

- `JAVACMD` - full path of the Java executable. Use this to invoke a different JVM than `JAVA_HOME/bin/java(.exe)`.
- `ANT_OPTS` - command-line arguments that should be passed to the JVM. For example, you can define properties or set the maximum Java heap size here.
- `ANT_ARGS` - Ant command-line arguments. For example, set `ANT_ARGS` to point to a different logger and to include the `-find` flag.

## Running Ant via Java

If you have installed Ant in the do-it-yourself way, Ant can be started with:

>     java -Dant.home=c:\ant org.apache.tools.ant.Main [options] [target]

These instructions actually do exactly the same as the `ant` command. The options and target are the same as when running Ant with the `ant` command. This example assumes you have set your classpath to include:

- `ant.jar`
- jars/classes for your XML parser
- the JDK's required jar/zip files

Copyright © 2001-2002 Apache Software Foundation. All rights Reserved.