< : Property>


Sets a property by name, or set of properties (from file or resource) in the project.

Properties are immutable: whoever sets a property first freezes it for the rest of the build; they are most definitely not variable.

There are five ways to set properties:

Although combinations of these ways are possible, only one should be used at a time. Problems might occur with the order in which properties are set, for instance.

The value part of the properties being set, might contain references to other properties. These references are resolved at the time these properties are set. This also holds for properties loaded from a property file.

Properties are case sensitive.


Attribute Description Type Required?
refid Sets a reference to an Ant datatype declared elsewhere. Only yields reasonable results for references PATH like structures or properties. Reference ?
url The url from which to load properties. URL ?
name The name of the property to set. String ?
classpath The classpath to use when looking up a resource. Path ?
userproperty boolean ?
file Filename of a property file to load. File ?
resource The resource name of a property file to load String ?
environment Prefix to use when retrieving environment variables. Thus if you specify environment="myenv" you will be able to access OS-specific environment variables via property names "myenv.PATH" or "myenv.TERM".

Note that if you supply a property name with a final "." it will not be doubled. ie environment="myenv." will still allow access of environment variables through "myenv.PATH" and "myenv.TERM". This functionality is currently only implemented on select platforms. Feel free to send patches to increase the number of platforms this functionality is supported on ;).
Note also that properties are case sensitive, even if the environment variables on your operating system are not, e.g. it will be ${env.Path} not ${env.PATH} on Windows 2000.

String ?
prefix Prefix to apply to properties loaded using file or resource. A "." is appended to the prefix if not specified. String ?
classpathref the classpath to use when looking up a resource, given as reference to a <path> defined elsewhere Reference ?
value The value of the property. String ?

Parameters accepted as nested elements

<classpath> ...

This object represents a path as used by CLASSPATH or PATH environment variable.

    <pathelement location="/path/to/file.jar" />
    <pathelement path="/path/to/file2.jar:/path/to/class2;/path/to/class3" />
    <pathelement location="/path/to/file3.jar" />
    <pathelement location="/path/to/file4.jar" />

The object implemention sometask must provide a method called createSomepath which returns an instance of Path. Nested path definitions are handled by the Path object and must be labeled pathelement.

The path element takes a parameter path which will be parsed and split into single elements. It will usually be used to define a path from an environment variable.

Attribute Description Type Required
refid Makes this instance in effect a reference to another Path instance.

You must not set another attribute or nest elements inside this element if you make it a reference.

Reference ?
path Parses a path definition and creates single PathElements. String ?