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diff --git a/framework/src/ant/apache-ant-1.9.6/manual/targets.html b/framework/src/ant/apache-ant-1.9.6/manual/targets.html deleted file mode 100644 index a778c950..00000000 --- a/framework/src/ant/apache-ant-1.9.6/manual/targets.html +++ /dev/null @@ -1,300 +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>Targets and Extension-Points</title> -</head> - -<body> - <h1><a name="targets">Targets</a></h1> - - <p>A target is a container of tasks that cooperate to reach a - desired state during the build process.</p> - - <p>Targets can depend on other targets and Apache Ant ensures that these - other targets have been executed before the current target. For - example you might have a target for compiling and a - target for creating a distributable. You can only build a - distributable when you have compiled first, so the distribute - target <i>depends on</i> the compile target.</p> - - <p>Ant tries to execute the targets in the <code>depends</code> - attribute in the order they appear (from left to right). Keep in - mind that it is possible that a target can get executed earlier - when an earlier target depends on it:</p> - -<blockquote> -<pre><target name="A"/> -<target name="B" depends="A"/> -<target name="C" depends="B"/> -<target name="D" depends="C,B,A"/></pre> -</blockquote> - - <p>Suppose we want to execute target D. From its - <code>depends</code> attribute, you might think that first target - C, then B and then A is executed. Wrong! C depends on B, and B - depends on A, so first A is executed, then B, then C, and finally - D.</p> - - <blockquote><pre><b>Call-Graph:</b> A --> B --> C --> D</pre></blockquote> - - <p>In a chain of dependencies stretching back from a given target - such as D above, each target gets executed only once, even when - more than one target depends on it. Thus, executing the D target - will first result in C being called, which in turn will first call - B, which in turn will first call A. After A, then B, then C have - executed, execution returns to the dependency list of D, which - will <u>not</u> call B and A, since they were already called in - process of dependency resolution for C and B respectively as - dependencies of D. Had no such dependencies been discovered in - processing C and B, B and A would have been executed after C in - processing D's dependency list.</p> - - <p>A target also has the ability to perform its execution if (or - unless) a property has been set. This allows, for example, better - control on the building process depending on the state of the - system (java version, OS, command-line property defines, etc.). - To make a target <i>sense</i> this property, you should add - the <code>if</code> (or <code>unless</code>) attribute with the - name of the property that the target should react - to. <strong>Note:</strong> In the most simple case Ant will only - check whether the property has been set, the value doesn't matter, - but using property expansions you can build more complex - conditions. See - <a href="properties.html#if+unless">the properties page</a> for - more details. For example:</p> - -<blockquote> - <pre><target name="build-module-A" if="module-A-present"/></pre> - <pre><target name="build-own-fake-module-A" unless="module-A-present"/></pre> -</blockquote> - - <p>In the first example, if the <code>module-A-present</code> - property is set (to any value, e.g. <i>false</i>), the target will - be run. In the second example, if - the <code>module-A-present</code> property is set (again, to any - value), the target will not be run.</p> - - <p>Only one propertyname can be specified in the if/unless - clause. If you want to check multiple conditions, you can use a - dependent target for computing the result for the check:</p> - -<blockquote><pre> -<target name="myTarget" depends="myTarget.check" if="myTarget.run"> - <echo>Files foo.txt and bar.txt are present.</echo> -</target> - -<target name="myTarget.check"> - <condition property="myTarget.run"> - <and> - <available file="foo.txt"/> - <available file="bar.txt"/> - </and> - </condition> -</target> -</pre></blockquote> - - <blockquote><pre><b>Call-Graph:</b> myTarget.check --> maybe(myTarget)</pre></blockquote> - - <p>If no <code>if</code> and no <code>unless</code> attribute is - present, the target will always be executed.</p> - - <p><b>Important:</b> the <code>if</code> and <code>unless</code> - attributes only enable or disable the target to which they are - attached. They do not control whether or not targets that a - conditional target depends upon get executed. In fact, they do - not even get evaluated until the target is about to be executed, - and all its predecessors have already run. - - <p>The optional <code>description</code> attribute can be used to - provide a one-line description of this target, which is printed by - the <code>-projecthelp</code> command-line option. Targets without - such a description are deemed internal and will not be listed, - unless either the <code>-verbose</code> or <code>-debug</code> - option is used.</p> - - <p>It is a good practice to place - your <a href="Tasks/tstamp.html">tstamp</a> tasks in a - so-called <i>initialization</i> target, on which all other targets - depend. Make sure that target is always the first one in the - depends list of the other targets. In this manual, most - initialization targets have the name <code>"init"</code>.</p> - <blockquote><pre> - <project> - <target name="init"> - <tstamp/> - </target> - <target name="otherTarget" depends="init"> - ... - </target> - </project> - </pre></blockquote> - - <p>Especially if you only have a few tasks you also could place these - tasks directly under the project tag (since Ant 1.6.0):</p> - <blockquote><pre> - <project> - <tstamp/> - </project> - </pre></blockquote> - - <p>If the depends attribute and the if/unless attribute are set, the - depends attribute is executed first.</p> - - <p>A target has the following attributes:</p> - - <table border="1" cellpadding="2" cellspacing="0"> - <tr> - <td valign="top"><b>Attribute</b></td> - <td valign="top"><b>Description</b></td> - <td align="center" valign="top"><b>Required</b></td> - </tr> - <tr> - <td valign="top">name</td> - <td valign="top">the name of the target.</td> - <td align="center" valign="top">Yes</td> - </tr> - <tr> - <td valign="top">depends</td> - <td valign="top">a comma-separated list of names of targets on - which this target depends.</td> - <td align="center" valign="top">No</td> - </tr> - <tr> - <td valign="top">if</td> - <td valign="top">the name of the property that must be set in - order for this target to execute, - or <a href="properties.html#if+unless">something evaluating to - true</a>.</td> - <td align="center" valign="top">No</td> - </tr> - <tr> - <td valign="top">unless</td> - <td valign="top">the name of the property that must not be set - in order for this target to execute, - or <a href="properties.html#if+unless">something evaluating to - false</a>.</td> - <td align="center" valign="top">No</td> - </tr> - <tr> - <td valign="top">description</td> - <td valign="top">a short description of this target's function.</td> - <td align="center" valign="top">No</td> - </tr> - <tr> - <td valign="top">extensionOf</td> - <td valign="top">Adds the current target to the depends list of - the named <a href="#extension-points">extension-point</a>. - <em>since Ant 1.8.0.</em></td> - <td align="center" valign="top">No</td> - </tr> - <tr> - <td valign="top">onMissingExtensionPoint</td> - <td valign="top">What to do if this target tries to extend a - missing - <a href="#extension-points">extension-point</a>. ("fail", - "warn", "ignore"). - <em>since Ant 1.8.2.</em></td> - <td align="center" valign="top">No. Not allowed unless - <code>extensionOf</code> is present. Defaults to <code>fail</code>. - </td> - </tr> - </table> - - <p>A target name can be any alphanumeric string valid in the - encoding of the XML file. The empty string "" is in this - set, as is comma "," and space " ". Please - avoid using these, as they will not be supported in future Ant - versions because of all the confusion they cause on command line and IDE. IDE support of - unusual target names, or any target name containing spaces, varies - with the IDE.</p> - - <p>Targets beginning with a hyphen such - as <code>"-restart"</code> are valid, and can be used to - name targets that should not be called directly from the command - line. <br> - For Ants main class every option starting with hyphen is an - option for Ant itself and not a target. For that reason calling these - target from command line is not possible. On the other hand IDEs usually - don't use Ants main class as entry point and calling them from the IDE - is usually possible.</p> - - <h1><a name="extension-points">Extension-Points</a></h1> - - <p><em>since Ant 1.8.0.</em></p> - - <p>Extension-Points are similar to targets in that they have a name and - a depends list and can be executed from the command line. Just - like targets they represent a state during the build process.</p> - - <p>Unlike targets they don't contain any tasks, their main purpose - is to collect targets that contribute to the desired state in - their depends list.</p> - - <p>Targets can add themselves to an extension-points's depends list via - their extensionOf attribute. The targets that add themselves will be - added after the targets of the explicit depends-attribute of the - extension-point, if multiple targets add themselves, their relative - order is not defined.</p> - - <p>The main purpose of an extension-point is to act as an extension - point for build files designed to - be <a href="Tasks/import.html">imported</a>. In the imported - file an extension-point defines a state that must be reached and - targets from other build files can join the depends list of said - extension-point in order to contribute to that state.</p> - - <p>For example your imported build file may need to compile code, it - might look like:</p> -<blockquote><pre> -<target name="create-directory-layout"> - ... -</target> -<extension-point name="ready-to-compile" - depends="create-directory-layout"/> -<target name="compile" depends="ready-to-compile"> - ... -</target> -</pre></blockquote> - - <blockquote><pre><b>Call-Graph:</b> create-directory-layout --> 'empty slot' --> compile</pre></blockquote> - - - <p>And you need to generate some source before compilation, then in - your main build file you may use something like</p> -<blockquote><pre> -<target name="generate-sources" - extensionOf="ready-to-compile"> - ... -</target> -</pre></blockquote> - - <blockquote><pre><b>Call-Graph:</b> create-directory-layout --> generate-sources --> compile</pre></blockquote> - - - <p>This will ensure that the <em>generate-sources</em> target is - executed before the <em>compile</em> target.</p> - - <p>Don't rely on the order of the depends list, - if <em>generate-sources</em> depends - on <em>create-directory-layout</em> then it must explicitly depend - on it via its own depends attribute.</p> -</body> -</html> |