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diff --git a/framework/src/ant/apache-ant-1.9.6/manual/properties.html b/framework/src/ant/apache-ant-1.9.6/manual/properties.html deleted file mode 100644 index e42d3a2a..00000000 --- a/framework/src/ant/apache-ant-1.9.6/manual/properties.html +++ /dev/null @@ -1,399 +0,0 @@ -<!-- - 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 - - http://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> - -<head> - <meta http-equiv="Content-Language" content="en-us"/> - <link rel="stylesheet" type="text/css" href="stylesheets/style.css"/> - <title>Properties and PropertyHelpers</title> -</head> - -<body> - <h1>Properties</h1> - - <p>Properties are key-value-pairs where Apache Ant tries to - expand <code>${key}</code> to <code>value</code> at runtime.</p> - - <p>There are many tasks that can set properties, the most common one - is the <a href="Tasks/property.html">property</a> task. In - addition properties can be defined - via <a href="running.html">command line arguments</a> or similar - mechanisms from outside of Ant.</p> - - <p>Normally property values can not be changed, once a property is - set, most tasks will not allow its value to be modified. In - general properties are of global scope, i.e. once they have been - defined they are available for any task or target invoked - subsequently - it is not possible to set a property in a child - build process created via - the <a href="Tasks/ant.html">ant</a>, antcall or subant tasks - and make it available to the calling build process, though.</p> - - <p>Starting with Ant 1.8.0 - the <a href="Tasks/local.html">local</a> task can be used to - create properties that are locally scoped to a target or - a <a href="Tasks/sequential.html">sequential</a> element like - the one of the <a href="Tasks/macrodef.html">macrodef</a> - task.</p> - - <h2><a name="built-in-props">Built-in Properties</a></h2> - - <p>Ant provides access to all system properties as if they had been - defined using a <code><property></code> task. For - example, <code>${os.name}</code> expands to the name of the - operating system.</p> - <p>For a list of system properties see - <a href="http://docs.oracle.com/javase/7/docs/api/java/lang/System.html#getProperties%28%29">the Javadoc of System.getProperties</a>. - </p> - - <p>In addition, Ant has some built-in properties:</p> -<pre><!-- TODO use <dl><dt><code>...</code></dt><dd>...</dd></dl> instead --> -basedir the absolute path of the project's basedir (as set - with the basedir attribute of <a href="using.html#projects"><project></a>). -ant.file the absolute path of the buildfile. -ant.version the version of Ant -ant.project.name the name of the project that is currently executing; - it is set in the name attribute of <project>. -ant.project.default-target - the name of the currently executing project's - default target; it is set via the default - attribute of <project>. -ant.project.invoked-targets - a comma separated list of the targets that have - been specified on the command line (the IDE, - an <ant> task ...) when invoking the current - project. - This property is set when the first target is executed. - So you can't use it in the implicit target (directly - under the <project> tag). -ant.java.version the JVM version Ant detected; currently it can hold - the values "1.7", "1.6", "1.5", - "1.4", "1.3" and "1.2". -ant.core.lib the absolute path of the <code>ant.jar</code> file. -</pre> - - <p>There is also another property, but this is set by the launcher - script and therefore maybe not set inside IDEs:</p> -<pre> -ant.home home directory of Ant -</pre> - - <p>The following property is only set if Ant is started via the - Launcher class (which means it may not be set inside IDEs - either):</p> -<pre> -ant.library.dir the directory that has been used to load Ant's - jars from. In most cases this is ANT_HOME/lib. -</pre> - - <h1><a name="propertyHelper">PropertyHelpers</a></h1> - - <p>Ant's property handling is accomplished by an instance of - <code>org.apache.tools.ant.PropertyHelper</code> associated with - the current Project. You can learn more about this class by - examining Ant's Java API. In Ant 1.8 the PropertyHelper class was - much reworked and now itself employs a number of helper classes - (actually instances of - the <code>org.apache.tools.ant.PropertyHelper$Delegate</code> - marker interface) to take care of discrete tasks such as property - setting, retrieval, parsing, etc. This makes Ant's property - handling highly extensible; also of interest is the - new <a href="Tasks/propertyhelper.html">propertyhelper</a> - task used to manipulate the PropertyHelper and its delegates from - the context of the Ant buildfile. - - <p>There are three sub-interfaces of <code>Delegate</code> that may be - useful to implement.</p> - - <ul> - <li><code>org.apache.tools.ant.property.PropertyExpander</code> is - responsible for finding the property name inside a string in the - first place (the default extracts <code>foo</code> - from <code>${foo}</code>). - - <p>This is the interface you'd implement if you wanted to invent - your own property syntax - or allow nested property expansions - since the default implementation doesn't balance braces - (see <a href="https://git-wip-us.apache.org/repos/asf?p=ant-antlibs-props.git;a=blob;f=src/main/org/apache/ant/props/NestedPropertyExpander.java;hb=HEAD"><code>NestedPropertyExpander</code> - in the "props" Antlib</a> for an example).</p> - </li> - - <li><code>org.apache.tools.ant.PropertyHelper$PropertyEvaluator</code> - is used to expand <code>${some-string}</code> into - an <code>Object</code>. - - <p>This is the interface you'd implement if you want to provide - your own storage independent of Ant's project instance - the - interface represents the reading end. An example for this - would - be <code>org.apache.tools.ant.property.LocalProperties</code> - which implements storage - for <a href="Tasks/local.html">local properties</a>.</p> - - <p>Another reason to implement this interface is if you wanted - to provide your own "property protocol" like - expanding <code>toString:foo</code> by looking up the project - reference foo and invoking <code>toString()</code> on it - (which is already implemented in Ant, see below).</p> - </li> - - <li><code>org.apache.tools.ant.PropertyHelper$PropertySetter</code> - is responsible for setting properties. - - <p>This is the interface you'd implement if you want to provide - your own storage independent of Ant's project instance - the - interface represents the reading end. An example for this - would - be <code>org.apache.tools.ant.property.LocalProperties</code> - which implements storage - for <a href="Tasks/local.html">local properties</a>.</p> - </li> - - </ul> - - <p>The default <code>PropertyExpander</code> looks similar to:</p> - -<pre> -public class DefaultExpander implements PropertyExpander { - public String parsePropertyName(String s, ParsePosition pos, - ParseNextProperty notUsed) { - int index = pos.getIndex(); - if (s.indexOf("${", index) == index) { - int end = s.indexOf('}', index); - if (end < 0) { - throw new BuildException("Syntax error in property: " + s); - } - int start = index + 2; - pos.setIndex(end + 1); - return s.substring(start, end); - } - return null; - } -} -</pre> - - <p>The logic that replaces <code>${toString:some-id}</code> with the - stringified representation of the object with - id <code>some-id</code> inside the current build is contained in a - PropertyEvaluator similar to the following code:</p> - -<pre> -public class ToStringEvaluator implements PropertyHelper.PropertyEvaluator { - private static final String prefix = "toString:"; - public Object evaluate(String property, PropertyHelper propertyHelper) { - Object o = null; - if (property.startsWith(prefix) && propertyHelper.getProject() != null) { - o = propertyHelper.getProject().getReference( - property.substring(prefix.length())); - } - return o == null ? null : o.toString(); - } -} -</pre> - - - <h1>Property Expansion</h1> - - <p>When Ant encounters a construct <code>${some-text}</code> the - exact parsing semantics are subject to the configured property - helper delegates.</p> - - <h2><code>$$</code> Expansion</h2> - - <p>In its default configuration Ant will expand the - text <code>$$</code> to a single <code>$</code> and suppress the - normal property expansion mechanism for the text immediately - following it, i.e. <code>$${key}</code> expands - to <code>${key}</code> and not <code>value</code> even though a - property named <code>key</code> was defined and had the - value <code>value</code>. This can be used to escape - literal <code>$</code> characters and is useful in constructs that - only look like property expansions or when you want to provide - diagnostic output like in</p> - -<pre> <echo>$${builddir}=${builddir}</echo></pre> - - <p>which will echo this message:</p> - -<pre> ${builddir}=build/classes</pre> - - <p>if the property <code>builddir</code> has the - value <code>build/classes</code>.</p> - - <p>In order to maintain backward compatibility with older Ant - releases, a single '$' character encountered apart from a - property-like construct (including a matched pair of french - braces) will be interpreted literally; that is, as '$'. The - "correct" way to specify this literal character, however, is by - using the escaping mechanism unconditionally, so that "$$" is - obtained by specifying "$$$$". Mixing the two approaches yields - unpredictable results, as "$$$" results in "$$".</p> - - <h2>Nesting of Braces</h2> - - <p>In its default configuration Ant will not try to balance braces - in property expansions, it will only consume the text up to the - first closing brace when creating a property name. I.e. when - expanding something like <code>${a${b}}</code> it will be - translated into two parts:</p> - - <ol> - <li>the expansion of property <code>a${b</code> - likely nothing - useful.</li> - <li>the literal text <code>}</code> resulting from the second - closing brace</li> - </ol> - - <p>This means you can't use easily expand properties whose names are - given by properties, but there - are <a href="http://ant.apache.org/faq.html#propertyvalue-as-name-for-property">some - workarounds</a> for older versions of Ant. With Ant 1.8.0 and the - <a href="http://ant.apache.org/antlib/props/">the props Antlib</a> - you can configure Ant to use - the <code>NestedPropertyExpander</code> defined there if you need - such a feature.</p> - - <h2>Expanding a "Property Name"</h2> - - <p>In its most simple form <code>${key}</code> is supposed to look - up a property named <code>key</code> and expand to the value of - the property. Additional <code>PropertyEvaluator</code>s may - result in a different interpretation of <code>key</code>, - though.</p> - - <p>The <a href="http://ant.apache.org/antlibs/props/">props - Antlib</a> provides a few interesting evaluators but there are - also a few built-in ones.</p> - - <h3><a name="toString">Getting the value of a Reference with - ${toString:}</a></h3> - - <p>Any Ant type which has been declared with a reference can also - its string value extracted by using the <code>${toString:}</code> - operation, with the name of the reference listed after - the <code>toString:</code> text. The <code>toString()</code> - method of the Java class instance that is referenced is invoked - -all built in types strive to produce useful and relevant output - in such an instance.</p> - - <p>For example, here is how to get a listing of the files in a fileset,<p> - -<pre> -<fileset id="sourcefiles" dir="src" includes="**/*.java" /> -<echo> sourcefiles = ${toString:sourcefiles} </echo> -</pre> - - <p>There is no guarantee that external types provide meaningful - information in such a situation</p> - - <h3><a name="ant.refid">Getting the value of a Reference with - ${ant.refid:}</a></h3> - - <p>Any Ant type which has been declared with a reference can also be - used as a property by using the <code>${ant.refid:}</code> - operation, with the name of the reference listed after - the <code>ant.refid:</code> text. The difference between this - operation and <a href="#toString"><code>${toString:}</code></a> is - that <code>${ant.refid:}</code> will expand to the referenced - object itself. In most circumstances the toString method will be - invoked anyway, for example if the <code>${ant.refid:}</code> is - surrounded by other text.</p> - - <p>This syntax is most useful when using a task with attribute - setters that accept objects other than String. For example if the - setter accepts a Resource object as in</p> -<pre> -public void setAttr(Resource r) { ... } -</pre> - - <p>then the syntax can be used to pass in resource subclasses - previously defined as references like</p> -<pre> - <url url="http://ant.apache.org/" id="anturl"/> - <my:task attr="${ant.refid:anturl}"/> -</pre> - - <h2><a name="if+unless">If/Unless Attributes</a></h2> - <p> - The <code><target></code> element and various tasks (such as - <code><fail></code>) and task elements (such as <code><test></code> - in <code><junit></code>) support <code>if</code> and <code>unless</code> - attributes which can be used to control whether the item is run or otherwise - takes effect. - </p> - <p> - In Ant 1.7.1 and earlier, these attributes could only be property names. - The item was enabled if a property with that name was defined - even to be - the empty string or <tt>false</tt> - and disabled if the property was not - defined. For example, the following works but there is no way to override - the file existence check negatively (only positively): - </p> - <pre> -<target name="-check-use-file"> - <available property="file.exists" file="some-file"/> -</target> -<target name="use-file" depends="-check-use-file" <b>if="file.exists"</b>> - <!-- do something requiring that file... --> -</target> -<target name="lots-of-stuff" depends="use-file,other-unconditional-stuff"/> - </pre> - <p> - As of Ant 1.8.0, you may instead use property expansion; a value of - <tt>true</tt> (or <tt>on</tt> or <tt>yes</tt>) will enable the - item, while <tt>false</tt> (or <tt>off</tt> or <tt>no</tt>) will - disable it. Other values are still assumed to be property - names and so the item is enabled only if the named property is defined. - </p> - <p> - Compared to the older style, this gives you additional flexibility, because - you can override the condition from the command line or parent scripts: - </p> - <pre> -<target name="-check-use-file" <b>unless="file.exists"</b>> - <available property="file.exists" file="some-file"/> -</target> -<target name="use-file" depends="-check-use-file" <b>if="${file.exists}"</b>> - <!-- do something requiring that file... --> -</target> -<target name="lots-of-stuff" depends="use-file,other-unconditional-stuff"/> - </pre> - <p> - Now <code>ant -Dfile.exists=false lots-of-stuff</code> will run - <code>other-unconditional-stuff</code> but not <code>use-file</code>, - as you might expect, and you can disable the condition from another script - too: - </p> - <pre> -<antcall target="lots-of-stuff"> - <param name="file.exists" value="false"/> -</antcall> - </pre> - <p> - Similarly, an <code>unless</code> attribute disables the item if it is - either the name of property which is defined, or if it evaluates to a - <tt>true</tt>-like value. For example, the following allows you to define - <tt>skip.printing.message=true</tt> in <tt>my-prefs.properties</tt> with - the results you might expect: - </p> - <pre> -<property file="my-prefs.properties"/> -<target name="print-message" <b>unless="${skip.printing.message}"</b>> - <echo>hello!</echo> -</target> - </pre> - -</body> |