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diff --git a/framework/src/ant/apache-ant-1.9.6/manual/projecthelper.html b/framework/src/ant/apache-ant-1.9.6/manual/projecthelper.html deleted file mode 100644 index fa07aea4..00000000 --- a/framework/src/ant/apache-ant-1.9.6/manual/projecthelper.html +++ /dev/null @@ -1,150 +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>The Apache Ant frontend: ProjectHelper</title> -</head> - -<body> -<h1>The Apache Ant frontend: ProjectHelper</h1> - -<h2><a name="definition">What is a ProjectHelper?</a></h2> - -<p> -The <code>ProjectHelper</code> in Apache Ant is responsible for parsing the build file -and creating java instances representing the build workflow. It also signals which -kind of file it can parse, and which file name it expects as default input file. -</p> - -<p> -Ant' default <code>ProjectHelper</code> -(<code>org.apache.tools.ant.helper.ProjectHelper2</code>) parses the -usual build.xml files. And if no build file is specified on the command line, it -will expect to find a file named <code>build.xml</code>. -</p> - -<p> -The immediate benefit of a such abstraction it that it is possible to make Ant -understand other kind of descriptive languages than XML. Some experiments have -been done around a pure java frontend, and a groovy one too (ask the dev mailing -list for further info about these). -</p> - -<p>Since Ant 1.8.2, the <a href="Tasks/import.html">import</a> task will also -try to use the proper helper to parse the imported file. So it is possible to -write different build files in different languages and have them import each -other. -</p> - -<h2><a name="repository">How is Ant is selecting the proper ProjectHelper</a></h2> - -<p> -Ant knows about several implementations of <code>ProjectHelper</code> -and has to decide which to use for each build file. -</p> - -<p>At startup Ant lists the all implementations found and keeps them -in the same order they've been found in an internal 'repository': -<ul> - <li>the first to be searched for is the one declared by the system property - <code>org.apache.tools.ant.ProjectHelper</code> (see - <a href="running.html#sysprops">Java System Properties</a>);</li> - <li>then it searches with its class loader for a <code>ProjectHelper</code> - service declarations in the META-INF: it searches in the classpath for a - file <code>META-INF/services/org.apache.tools.ant.ProjectHelper</code>. - This file will just contain the fully qualified name of the - implementation of <code>ProjectHelper</code> to instanciate;</li> - <li>it will also search with the system class loader for - <code>ProjectHelper</code> service declarations in the META-INF;</li> - <li>last but not least it will add its default <code>ProjectHelper</code> - that can parse classical build.xml files.</li> -</ul> -In case of an error while trying to instanciate a <code>ProjectHelper</code>, Ant -will log an error but won't stop. If you want further debugging -info about the <code>ProjectHelper</code> internal 'repository', use the <b>system</b> -property <code>ant.project-helper-repo.debug</code> and set it to -<code>true</code>; the full stack trace will then also be printed. -</p> - -<p> -When Ant is expected to parse a file, it will ask the -<code>ProjectHelper</code> repository to find an implementation that will be -able to parse the input file. Actually it will just iterate over the ordered list -and the first implementation that returns <code>true</code> to -<code>supportsBuildFile(File buildFile)</code> will be selected. -</p> - -<p> -When Ant is started and no input file has been specified, it will search for -a default input file. It will iterate over list of <code>ProjectHelper</code>s -and will select the first one that expects a default file that actually exist. -</p> - -<h2><a name="writing">Writing your own ProjectHelper</a></h2> - -<p> -The class <code>org.apache.tools.ant.ProjectHelper</code> is the API expected to -be implemented. So write your own <code>ProjectHelper</code> by extending that -abstract class. You are then expected to implement at least the function -<code>parse(Project project, Object source)</code>. Note also that your -implementation will be instanciated by Ant, and it is expecting a default -constructor with no arguments. -</p> - -<p> -There are some functions that will help you define what your helper is -capable of and what is is expecting: -<ul> - <li><code>getDefaultBuildFile()</code>: defines which file name is expected if - none provided</li> - <li><code>supportsBuildFile(File buildFile)</code>: defines if your parser - can parse the input file</li> - - <li><code>canParseAntlibDescriptor(URL url)</code>: whether your - implementation is capable of parsing a given Antlib - descriptor. The base class returns <code>false</code></li> - <li><code>parseAntlibDescriptor(Project containingProject, URL - source)</code>: invoked to actually parse the Antlib - descriptor if your implementation returned <code>true</code> - for the previous method.</li> -</ul> -</p> - -<p> -Now that you have your implementation ready, you have to declare it to Ant. Three -solutions here: -<ul> - <li>use the system property <code>org.apache.tools.ant.ProjectHelper</code> - (see also the <a href="running.html#sysprops">Java System Properties</a>);</li> - <li>use the service file in META-INF: in the jar you will build with your - implementation, add a file - <code>META-INF/services/org.apache.tools.ant.ProjectHelper</code>. - And then in this file just put the fully qualified name of your - implementation</li> - <li>use the <a href="Tasks/projecthelper.html">projecthelper</a> task (since - Ant 1.8.2) which will install dynamically an helper in the internal helper - 'repository'. Then your helper can be used on the next call to the - <a href="Tasks/import.html">import</a> task.</li> -</ul> -</p> - -</body> -</html> - |