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| author |   Ashlee Young <ashlee@onosfw.com> | 2015-10-23 10:05:40 -0700 |
|---|---|---|
| committer | Ashlee Young <ashlee@onosfw.com> | 2015-10-23 10:05:40 -0700 |
| commit | b9421dc80af485591a9c50cc8921f912e0def11e (patch) | |
| tree | 93f0935070ca2b2e661f281ac22761879f7cf893 /framework/src/ant/apache-ant-1.9.6/manual/develop.html | |
| parent | 753a6c60f47f3ac4f270005b65e9d6481de8eb68 (diff) | |
Removing sources to replace with download links instead.
Change-Id: Ie28789a725051aec0d1b04dd291b7690a7898668
Signed-off-by: Ashlee Young <ashlee@onosfw.com>
Diffstat (limited to 'framework/src/ant/apache-ant-1.9.6/manual/develop.html')
| -rw-r--r-- | framework/src/ant/apache-ant-1.9.6/manual/develop.html | 544 |
1 files changed, 0 insertions, 544 deletions
diff --git a/framework/src/ant/apache-ant-1.9.6/manual/develop.html b/framework/src/ant/apache-ant-1.9.6/manual/develop.html deleted file mode 100644 index ed06d301..00000000 --- a/framework/src/ant/apache-ant-1.9.6/manual/develop.html +++ /dev/null @@ -1,544 +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>Writing Your Own Task</title> -</head> - -<body> -<h1>Developing with Apache Ant</h1> - -<h2><a name="writingowntask">Writing Your Own Task</a></h2> -<p>It is very easy to write your own task:</p> -<ol> - <li>Create a Java class that extends <code>org.apache.tools.ant.Task</code> - or <a href="base_task_classes.html">another class</a> that was designed to be extended.</li> - - <li>For each attribute, write a <i>setter</i> method. The setter method must be a - <code>public void</code> method that takes a single argument. The - name of the method must begin with <code>set</code>, followed by the - attribute name, with the first character of the name in uppercase, and the rest in - lowercase<a href="#footnote-1"><sup>*</sup></a>. That is, to support an attribute named - <code>file</code> you create a method <code>setFile</code>. - Depending on the type of the argument, Ant will perform some - conversions for you, see <a href="#set-magic">below</a>.</li> - - <li>If your task shall contain other tasks as nested elements (like - <a href="Tasks/parallel.html"><code>parallel</code></a>), your - class must implement the interface - <code>org.apache.tools.ant.TaskContainer</code>. If you do so, your - task can not support any other nested elements. See - <a href="#taskcontainer">below</a>.</li> - - <li>If the task should support character data (text nested between the - start end end tags), write a <code>public void addText(String)</code> - method. Note that Ant does <strong>not</strong> expand properties on - the text it passes to the task.</li> - - <li>For each nested element, write a <i>create</i>, <i>add</i> or - <i>addConfigured</i> method. A create method must be a - <code>public</code> method that takes no arguments and returns an - <code>Object</code> type. The name of the create method must begin - with <code>create</code>, followed by the element name. An add (or - addConfigured) method must be a <code>public void</code> method that - takes a single argument of an <code>Object</code> type with a - no-argument constructor. The name of the add (addConfigured) method - must begin with <code>add</code> (<code>addConfigured</code>), - followed by the element name. For a more complete discussion see - <a href="#nested-elements">below</a>.</li> - - <li>Write a <code>public void execute</code> method, with no arguments, that - throws a <code>BuildException</code>. This method implements the task - itself.</li> -</ol> - -<hr> -<p><a name="footnote-1">*</a> Actually the case of the letters after -the first one doesn't really matter to Ant, using all lower case is a -good convention, though.</p> - -<h3>The Life-cycle of a Task</h3> -<ol> - <li> - The xml element that contains the tag corresponding to the - task gets converted to an UnknownElement at parser time. - This UnknownElement gets placed in a list within a target - object, or recursively within another UnknownElement. - </li> - <li> - When the target is executed, each UnknownElement is invoked - using an <code>perform()</code> method. This instantiates - the task. This means that tasks only gets - instantiated at run time. - </li> - - <li>The task gets references to its project and location inside the - buildfile via its inherited <code>project</code> and - <code>location</code> variables.</li> - - <li>If the user specified an <code>id</code> attribute to this task, - the project - registers a reference to this newly created task, at run - time.</li> - - <li>The task gets a reference to the target it belongs to via its - inherited <code>target</code> variable.</li> - - <li><code>init()</code> is called at run time.</li> - - <li>All child elements of the XML element corresponding to this task - are created via this task's <code>createXXX()</code> methods or - instantiated and added to this task via its <code>addXXX()</code> - methods, at run time. Child elements corresponding - to <code>addConfiguredXXX()</code> are created at this point but - the actual <code>addCondifgired</code> method is not called.</li> - - <li>All attributes of this task get set via their corresponding - <code>setXXX</code> methods, at runtime.</li> - - <li>The content character data sections inside the XML element - corresponding to this task is added to the task via its - <code>addText</code> method, at runtime.</li> - - <li>All attributes of all child elements get set via their corresponding - <code>setXXX</code> methods, at runtime.</li> - - <li>If child elements of the XML element corresponding to this task - have been created for <code>addConfiguredXXX()</code> methods, - those methods get invoked now.</li> - - <li><a name="execute"><code>execute()</code></a> is called at runtime. - If <code>target1</code> and <code>target2</code> both depend - on <code>target3</code>, then running - <code>'ant target1 target2'</code> will run all tasks in - <code>target3</code> twice.</li> -</ol> - -<h3><a name="set-magic">Conversions Ant will perform for attributes</a></h3> - -<p>Ant will always expand properties before it passes the value of an -attribute to the corresponding setter method. <b>Since Ant 1.8</b>, it is -possible to <a href="Tasks/propertyhelper.html">extend Ant's property handling</a> -such that a non-string Object may be the result of the evaluation of a string -containing a single property reference. These will be assigned directly via -setter methods of matching type. Since it requires some beyond-the-basics -intervention to enable this behavior, it may be a good idea to flag attributes -intended to permit this usage paradigm. -</p> - -<p>The most common way to write an attribute setter is to use a -<code>java.lang.String</code> argument. In this case Ant will pass -the literal value (after property expansion) to your task. But there -is more! If the argument of you setter method is</p> - -<ul> - - <li><code>boolean</code>, your method will be passed the value - <i>true</i> if the value specified in the build file is one of - <code>true</code>, <code>yes</code>, or <code>on</code> and - <i>false</i> otherwise.</li> - - <li><code>char</code> or <code>java.lang.Character</code>, your - method will be passed the first character of the value specified in - the build file.</li> - - <li>any other primitive type (<code>int</code>, <code>short</code> - and so on), Ant will convert the value of the attribute into this - type, thus making sure that you'll never receive input that is not a - number for that attribute.</li> - - <li><code>java.io.File</code>, Ant will first determine whether the - value given in the build file represents an absolute path name. If - not, Ant will interpret the value as a path name relative to the - project's basedir.</li> - - <li><code>org.apache.tools.ant.types.Resource</code> - <code>org.apache.tools.ant.types.Resource</code>, Ant will - resolve the string as a <code>java.io.File</code> as above, then - pass in as a <code>org.apache.tools.ant.types.resources.FileResource</code>. - <b>Since Ant 1.8</b> - </li> - - <li><code>org.apache.tools.ant.types.Path</code>, Ant will tokenize - the value specified in the build file, accepting <code>:</code> and - <code>;</code> as path separators. Relative path names will be - interpreted as relative to the project's basedir.</li> - - <li><code>java.lang.Class</code>, Ant will interpret the value - given in the build file as a Java class name and load the named - class from the system class loader.</li> - - <li>any other type that has a constructor with a single - <code>String</code> argument, Ant will use this constructor to - create a new instance from the value given in the build file.</li> - - <li>A subclass of - <code>org.apache.tools.ant.types.EnumeratedAttribute</code>, Ant - will invoke this classes <code>setValue</code> method. Use this if - your task should support enumerated attributes (attributes with - values that must be part of a predefined set of values). See - <code>org/apache/tools/ant/taskdefs/FixCRLF.java</code> and the - inner <code>AddAsisRemove</code> class used in <code>setCr</code> - for an example.</li> - - <li>A (Java 5) enumeration. Ant will call the setter with the enum constant - matching the value given in the build file. This is easier than using - <code>EnumeratedAttribute</code> and can result in cleaner code, but of course - your task will not run on JDK 1.4 or earlier. Note that any override of - <code>toString()</code> in the enumeration is ignored; the build file must use - the declared name (see <code>Enum.getName()</code>). You may wish to use lowercase - enum constant names, in contrast to usual Java style, to look better in build files. - <em>As of Ant 1.7.0.</em></li> - -</ul> - -<p>What happens if more than one setter method is present for a given -attribute? A method taking a <code>String</code> argument will always -lose against the more specific methods. If there are still more -setters Ant could chose from, only one of them will be called, but we -don't know which, this depends on the implementation of your Java -virtual machine.</p> - -<h3><a name="nested-elements">Supporting nested elements</a></h3> - -<p>Let's assume your task shall support nested elements with the name -<code>inner</code>. First of all, you need a class that represents -this nested element. Often you simply want to use one of Ant's -classes like <code>org.apache.tools.ant.types.FileSet</code> to -support nested <code>fileset</code> elements.</p> - -<p>Attributes of the nested elements or nested child elements of them -will be handled using the same mechanism used for tasks (i.e. setter -methods for attributes, addText for nested text and -create/add/addConfigured methods for child elements).</p> - -<p>Now you have a class <code>NestedElement</code> that is supposed to -be used for your nested <code><inner></code> elements, you have -three options:</p> - -<ol> - <li><code>public NestedElement createInner()</code></li> - <li><code>public void addInner(NestedElement anInner)</code></li> - <li><code>public void addConfiguredInner(NestedElement anInner)</code></li> -</ol> - -<p>What is the difference?</p> - -<p>Option 1 makes the task create the instance of -<code>NestedElement</code>, there are no restrictions on the type. -For the options 2 and 3, Ant has to create an instance of -<code>NestedInner</code> before it can pass it to the task, this -means, <code>NestedInner</code> must have a <code>public</code> no-arg - constructor or a <code>public</code> one-arg constructor - taking a Project class as a parameter. -This is the only difference between options 1 and 2.</p> - -<p>The difference between 2 and 3 is what Ant has done to the object -before it passes it to the method. <code>addInner</code> will receive -an object directly after the constructor has been called, while -<code>addConfiguredInner</code> gets the object <em>after</em> the -attributes and nested children for this new object have been -handled.</p> - -<p>What happens if you use more than one of the options? Only one of -the methods will be called, but we don't know which, this depends on -the implementation of your Java virtual machine.</p> - -<h3><a name="nestedtype">Nested Types</a></h3> -If your task needs to nest an arbitrary type that has been defined - using <code><typedef></code> you have two options. - <ol> - <li><code>public void add(Type type)</code></li> - <li><code>public void addConfigured(Type type)</code></li> - </ol> - The difference between 1 and 2 is the same as between 2 and 3 in the - previous section. - <p> - For example suppose one wanted to handle objects object of type - org.apache.tools.ant.taskdefs.condition.Condition, one may - have a class: - </p> - <blockquote> - <pre> -public class MyTask extends Task { - private List conditions = new ArrayList(); - public void add(Condition c) { - conditions.add(c); - } - public void execute() { - // iterator over the conditions - } -} - </pre> - </blockquote> - <p> - One may define and use this class like this: - </p> - <blockquote> - <pre> -<taskdef name="mytask" classname="MyTask" classpath="classes"/> -<typedef name="condition.equals" - classname="org.apache.tools.ant.taskdefs.conditions.Equals"/> -<mytask> - <condition.equals arg1="${debug}" arg2="true"/> -</mytask> - </pre> - </blockquote> - <p> - A more complicated example follows: - </p> - <blockquote> - <pre> -public class Sample { - public static class MyFileSelector implements FileSelector { - public void setAttrA(int a) {} - public void setAttrB(int b) {} - public void add(Path path) {} - public boolean isSelected(File basedir, String filename, File file) { - return true; - } - } - - interface MyInterface { - void setVerbose(boolean val); - } - - public static class BuildPath extends Path { - public BuildPath(Project project) { - super(project); - } - - public void add(MyInterface inter) {} - public void setUrl(String url) {} - } - - public static class XInterface implements MyInterface { - public void setVerbose(boolean x) {} - public void setCount(int c) {} - } -} - </pre> - </blockquote> - <p> - This class defines a number of static classes that implement/extend - Path, MyFileSelector and MyInterface. These may be defined and used - as follows: - </p> - <pre> - <blockquote> -<typedef name="myfileselector" classname="Sample$MyFileSelector" - classpath="classes" loaderref="classes"/> -<typedef name="buildpath" classname="Sample$BuildPath" - classpath="classes" loaderref="classes"/> -<typedef name="xinterface" classname="Sample$XInterface" - classpath="classes" loaderref="classes"/> - -<copy todir="copy-classes"> - <fileset dir="classes"> - <myfileselector attra="10" attrB="-10"> - <buildpath path="." url="abc"> - <xinterface count="4"/> - </buildpath> - </myfileselector> - </fileset> -</copy> - </blockquote> - </pre> - -<h3><a name="taskcontainer">TaskContainer</a></h3> - -<p>The <code>TaskContainer</code> consists of a single method, -<code>addTask</code> that basically is the same as an <a -href="#nested-elements">add method</a> for nested elements. The task -instances will be configured (their attributes and nested elements -have been handled) when your task's <code>execute</code> method gets -invoked, but not before that.</p> - -<p>When we <a href="#execute">said</a> <code>execute</code> would be -called, we lied ;-). In fact, Ant will call the <code>perform</code> -method in <code>org.apache.tools.ant.Task</code>, which in turn calls -<code>execute</code>. This method makes sure that <a -href="#buildevents">Build Events</a> will be triggered. If you -execute the task instances nested into your task, you should also -invoke <code>perform</code> on these instances instead of -<code>execute</code>.</p> - -<h3>Example</h3> -<p>Let's write our own task, which prints a message on the -<code>System.out</code> stream. -The task has one attribute, called <code>message</code>.</p> -<blockquote> -<pre> -package com.mydomain; - -import org.apache.tools.ant.BuildException; -import org.apache.tools.ant.Task; - -public class MyVeryOwnTask extends Task { - private String msg; - - // The method executing the task - public void execute() throws BuildException { - System.out.println(msg); - } - - // The setter for the "message" attribute - public void setMessage(String msg) { - this.msg = msg; - } -} -</pre> -</blockquote> -<p>It's really this simple ;-)</p> -<p>Adding your task to the system is rather simple too:</p> -<ol> - <li>Make sure the class that implements your task is in the classpath when - starting Ant.</li> - <li>Add a <code><taskdef></code> element to your project. - This actually adds your task to the system.</li> - <li>Use your task in the rest of the buildfile.</li> -</ol> - -<h3>Example</h3> -<blockquote> -<pre> -<?xml version="1.0"?> - -<project name="OwnTaskExample" default="main" basedir="."> - <taskdef name="mytask" classname="com.mydomain.MyVeryOwnTask"/> - - <target name="main"> - <mytask message="Hello World! MyVeryOwnTask works!"/> - </target> -</project> -</pre> -</blockquote> - -<h3>Example 2</h3> -To use a task directly from the buildfile which created it, place the -<code><taskdef></code> declaration inside a target -<i>after the compilation</i>. Use the <code>classpath</code> attribute of -<code><taskdef></code> to point to where the code has just been -compiled. -<blockquote> -<pre> -<?xml version="1.0"?> - -<project name="OwnTaskExample2" default="main" basedir="."> - - <target name="build" > - <mkdir dir="build"/> - <javac srcdir="source" destdir="build"/> - </target> - - <target name="declare" depends="build"> - <taskdef name="mytask" - classname="com.mydomain.MyVeryOwnTask" - classpath="build"/> - </target> - - <target name="main" depends="declare"> - <mytask message="Hello World! MyVeryOwnTask works!"/> - </target> -</project> -</pre> -</blockquote> - -<p>Another way to add a task (more permanently), is to add the task name and -implementing class name to the <code>default.properties</code> file in the -<code>org.apache.tools.ant.taskdefs</code> -package. Then you can use it as if it were a built-in task.</p> - -<hr> -<h2><a name="buildevents">Build Events</a></h2> -<p>Ant is capable of generating build events as it performs the tasks necessary to build a project. -Listeners can be attached to Ant to receive these events. This capability could be used, for example, -to connect Ant to a GUI or to integrate Ant with an IDE. -</p> -<p>To use build events you need to create an ant <code>Project</code> object. You can then call the -<code>addBuildListener</code> method to add your listener to the project. Your listener must implement -the <code>org.apache.tools.antBuildListener</code> interface. The listener will receive BuildEvents -for the following events</p> -<ul> - <li>Build started</li> - <li>Build finished</li> - <li>Target started</li> - <li>Target finished</li> - <li>Task started</li> - <li>Task finished</li> - <li>Message logged</li> -</ul> - -<p>If the build file invokes another build file via -<a href="Tasks/ant.html"><code><ant></code></a> or -<a href="Tasks/subant.html"><code><subant></code></a> or uses -<a href="Tasks/antcall.html"><code><antcall></code></a>, you are creating a -new Ant "project" that will send target and task level events of its -own but never sends build started/finished events. Ant 1.6.2 -introduces an extension of the BuildListener interface named -SubBuildListener that will receive two new events for</p> -<ul> - <li>SubBuild started</li> - <li>SubBuild finished</li> -</ul> -<p>If you are interested in those events, all you need to do is to -implement the new interface instead of BuildListener (and register the -listener, of course).</p> - -<p>If you wish to attach a listener from the command line you may use the -<code>-listener</code> option. For example:</p> -<blockquote> - <pre>ant -listener org.apache.tools.ant.XmlLogger</pre> -</blockquote> -<p>will run Ant with a listener that generates an XML representation of the build progress. This -listener is included with Ant, as is the default listener, which generates the logging to standard output.</p> - -<p><b>Note: </b>A listener must not access System.out and System.err directly since output on -these streams is redirected by Ant's core to the build event system. Accessing these -streams can cause an infinite loop in Ant. Depending on the version of Ant, this will -either cause the build to terminate or the Java VM to run out of Stack space. A logger, also, may -not access System.out and System.err directly. It must use the streams with which it has -been configured.</p> - -<p><b>Note2:</b> All methods of a BuildListener except for the "Build - Started" and "Build Finished" events may occur on several threads - simultaneously - for example while Ant is executing - a <code><parallel></code> task.</p> - -<hr> -<h2><a name="integration">Source code integration</a></h2> - -<p>The other way to extend Ant through Java is to make changes to existing tasks, which is positively encouraged. -Both changes to the existing source and new tasks can be incorporated back into the Ant codebase, which -benefits all users and spreads the maintenance load around.</p> - -<p>Please consult the -<a href="http://www.apache.org/foundation/getinvolved.html">Getting Involved</a> pages on the Apache web site -for details on how to fetch the latest source and how to submit changes for reincorporation into the -source tree.</p> - -<p>Ant also has some -<a href="http://ant.apache.org/ant_task_guidelines.html">task guidelines</a> -which provides some advice to people developing and testing tasks. Even if you intend to -keep your tasks to yourself, you should still read this as it should be informative.</p> - -</body> -</html> - |