Regexp

Regexp

Regexp represents a regular expression.

Parameters

Examples

 <regexp id="myregexp" pattern="alpha(.+)beta"/>

Defines a regular expression for later use with id myregexp.

 <regexp refid="myregexp"/>

Use the regular expression with id myregexp.

Choice of regular expression implementation

Apache Ant comes withwrappers forthe java.util.regex package,jakarta-regexpand jakarta-ORO,See installation dependencies concerning the supporting libraries.

The property ant.regexp.regexpimpl governs which regular expression implementation will be chosen.Possible values for this property are :

• org.apache.tools.ant.util.regexp.Jdk14RegexpRegexp
• org.apache.tools.ant.util.regexp.JakartaOroRegexp
• org.apache.tools.ant.util.regexp.JakartaRegexpRegexp

There are cross-platform issues for matches related to line terminator.For example if you use $ to anchor your regular expression on the end of a linethe results might be very different depending on both your platform and the regularexpression library you use. It is 'highly recommended' that you test your pattern onboth Unix and Windows platforms before you rely on it.

• Jakarta Oro defines a line terminator as '' and is consistent with Perl.
• Jakarta RegExp uses a system-dependent line terminator.
• JDK 1.4 uses '', '', 'u0085', 'u2028', 'u2029' as a default but is configured in the wrapper to use only '' (UNIX_LINE)

Usage

• ReplaceRegExp task
• LineContainsRegexp filter

These string filters also use the mechanism of regexp to choose a regular expression implementation :

• ContainsRegex string filter
• ReplaceRegex string filter
• filename selector
• name resource selector
• containsregexp selector