<!DOCTYPE html> <!-- Licensed to the Apache Software Foundation (ASF) under one or more contributor license agreements. See the NOTICE file distributed with this work for additional information regarding copyright ownership. The ASF licenses this file to You under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at https://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License. --> <html lang="en"> <head> <link rel="stylesheet" type="text/css" href="../stylesheets/style.css"> <title>Condition Task</title> </head> <body> <h2 id="condition">Condition</h2> <h3>Description</h3> <p>Sets a property if a certain condition holds true—this is a generalization of <a href="available.html">Available</a> and <a href="uptodate.html">Uptodate</a>.</p> <p>If the condition holds true, the property value is set to <q>true</q> by default; otherwise, the property is not set. You can set the value to something other than the default by specifying the <var>value</var> attribute.</p> <p>Conditions are specified as <a href="#nested">nested elements</a>, you must specify exactly one condition.</p> <h3>Parameters</h3> <table class="attr"> <tr> <th scope="col">Attribute</th> <th scope="col">Description</th> <th scope="col">Required</th> </tr> <tr> <td>property</td> <td>The name of the property to set.</td> <td>Yes</td> </tr> <tr> <td>value</td> <td>The value to set the property to.</td> <td>No; defaults to <q>true</q></td> </tr> <tr> <td>else</td> <td>The value to set the property to if the condition evaluates to <q>false</q>. <em>Since Apache Ant 1.6.3</em> </td> <td>No; by default the property will remain unset</td> </tr> </table> <h3 id="nested">Parameters specified as nested elements</h3> <p>All conditions to test are specified as nested elements, for a complete list see <a href="conditions.html">here</a>.</p> <h3>Examples</h3> <p>Set the property <code>javamail.complete</code> if both the JavaBeans Activation Framework and JavaMail are available in the classpath.</p> <pre> <condition property="javamail.complete"> <and> <available classname="javax.activation.DataHandler"/> <available classname="javax.mail.Transport"/> </and> </condition></pre> <p>Set the property <code>isMacOsButNotMacOsX</code> if the current operating system is MacOS, but not MacOS X/macOS—which Ant considers to be in the Unix family as well.</p> <pre> <condition property="isMacOsButNotMacOsX"> <and> <os family="mac"/> <not> <os family="unix"/> </not> </and> </condition></pre> <p>Set the property <code>isSunOSonSparc</code> if the current operating system is SunOS and if it is running on a SPARC architecture.</p> <pre> <condition property="isSunOSonSparc"> <os name="SunOS" arch="sparc"/> </condition></pre> </body> </html>