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diff --git a/framework/src/ant/apache-ant-1.9.6/manual/Types/selectors-program.html b/framework/src/ant/apache-ant-1.9.6/manual/Types/selectors-program.html deleted file mode 100644 index 074a5426..00000000 --- a/framework/src/ant/apache-ant-1.9.6/manual/Types/selectors-program.html +++ /dev/null @@ -1,244 +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>Programming Selectors in Apache Ant</title> - </head> - - <body> - <h2>Programming your own Selectors</h2> - - <h3>Selector Programming API</h3> - - <p>Want to define your own selectors? It's easy!</p> - - <p>First, pick the type of selector that you want to define. There - are three types, and a recipe for each one follows. Chances are - you'll want to work with the first one, Custom Selectors.</p> - - <ol> - <li>Custom Selectors - - <p>This is the category that Apache Ant provides specifically for you to - define your own Selectors. Anywhere you want to use your selector - you use the <code><custom></code> element and specify - the class name of your selector within it. See the - <a href="selectors.html#customselect">Custom Selectors</a> - section of the Selector page for details. The - <code><custom></code> element can be used anywhere - the core selectors can be used. It can be contained within - <a href="selectors.html#selectcontainers">Selector Containers</a>, - for example.</p> - - <p>To create a new Custom Selector, you have to create a class that - implements - <code>org.apache.tools.ant.types.selectors.ExtendFileSelector</code>. - The easiest way to do that is through the convenience base class - <code>org.apache.tools.ant.types.selectors.BaseExtendSelector</code>, - which provides all of the methods for supporting - <code><param></code> tags. First, override the - <code>isSelected()</code> method, and optionally the - <code>verifySettings()</code> method. If your custom - selector requires parameters to be set, you can also override - the <code>setParameters()</code> method and interpret the - parameters that are passed in any way you like. Several of the - core selectors demonstrate how to do that because they can - also be used as custom selectors.</p> - - <li>Core Selectors - - <p>These are the selectors used by Ant itself. To implement one of - these, you will have to alter some of the classes contained within - Ant.</p> - - <ul> - <li><p>First, create a class that implements - <code>org.apache.tools.ant.types.selectors.FileSelector</code>. - You can either choose to implement all methods yourself from - scratch, or you can extend - <code>org.apache.tools.ant.types.selectors.BaseSelector</code> - instead, a convenience class that provides reasonable default - behaviour for many methods.</p> - - <p>There is only one method required. - <code>public boolean isSelected(File basedir, String filename, - File file)</code> - is the real purpose of the whole exercise. It returns true - or false depending on whether the given file should be - selected from the list or not.</p> - - <p>If you are using - <code>org.apache.tools.ant.types.selectors.BaseSelector</code> - there are also some predefined behaviours you can take advantage - of. Any time you encounter a problem when setting attributes or - adding tags, you can call setError(String errmsg) and the class - will know that there is a problem. Then, at the top of your - <code>isSelected()</code> method call <code>validate()</code> and - a BuildException will be thrown with the contents of your error - message. The <code>validate()</code> method also gives you a - last chance to check your settings for consistency because it - calls <code>verifySettings()</code>. Override this method and - call <code>setError()</code> within it if you detect any - problems in how your selector is set up.</p> - - <p>You may also want to override <code>toString()</code>.</p> - - <li><p>Put an <code>add</code> method for your selector in - <code>org.apache.tools.ant.types.selectors.SelectorContainer</code>. - This is an interface, so you will also have to add an implementation - for the method in the classes which implement it, namely - <code>org.apache.tools.ant.types.AbstractFileSet</code>, - <code>org.apache.tools.ant.taskdefs.MatchingTask</code> and - <code>org.apache.tools.ant.types.selectors.BaseSelectorContainer</code>. - Once it is in there, it will be available everywhere that core - selectors are appropriate.</p> - </ul> - - <li>Selector Containers - <p>Got an idea for a new Selector Container? Creating a new one is - no problem:</p> - <ul> - <li><p>Create a new class that implements - <code>org.apache.tools.ant.types.selectors.SelectorContainer</code>. - This will ensure that your new - Container can access any new selectors that come along. Again, there - is a convenience class available for you called - <code>org.apache.tools.ant.types.selectors.BaseSelectorContainer</code>. - </p> - <li><p>Implement the - <code>public boolean isSelected(String filename, File file)</code> - method to do the right thing. Chances are you'll want to iterate - over the selectors under you, so use - <code>selectorElements()</code> to get an iterator that will do - that.</p> - <li><p>Again, put an <code>add</code> method for your container in - <code>org.apache.tools.ant.types.selectors.SelectorContainer</code> - and its implementations - <code>org.apache.tools.ant.types.AbstractFileSet</code> and - <code>org.apache.tools.ant.types.selectors.BaseSelectorContainer</code>. - </p> - </ul> - </ol> - - <h3>Testing Selectors</h3> - - <p>For a robust component (and selectors are (Project)Components) tests are - necessary. For testing Tasks we use JUnit TestCases - more specific - <tt>org.apache.tools.ant.BuildFileRule extends org.junit.rules.ExternalResource</tt>. - Some of its features like configure the (test) project by reading its buildfile and - execute targets we need for selector tests also. Therefore we use that BuildFileRule. - But testing selectors requires some more work: having a set of files, instantiate - and configure the selector, check the selection work and more. Because we usually - extend <tt>BaseExtendSelector</tt> its features have to be tested also (e.g. setError()). - </p> - - <p>That's why we have a test rule for doing our selector tests: - <tt>org.apache.tools.ant.types.selectors.BaseSelectorRule</tt>.</p> - - <p>This class extends ExternalResource and therefore can included in the set of Ant's - unit tests. It holds an instance of preconfigured BuildFileRule. Configuration - is done by parsing the src/etc/testcases/types/selectors.xml. BaseSelectorRule - then gives us helper methods for handling multiple selections. </p> - - <p>Because the term "testcase" or "testenvironment" are so often used, this - special testenvironment got a new name: <i>bed</i>. The setup and cleanup of - the bed is all handled by the BaseSelectorRule so any test only has to handle - the actual test scenarios</p> - - <p>A usual test scenario is:</p> - <ol> - <li>instantiate the selector</li> - <li>configure the selector</li> - <li>let the selector do some work</li> - <li>verify the work</li> - </ol> - - - - <p>An example test would be:<pre> -package org.apache.tools.ant.types.selectors; - -public class MySelectorTest { - - @Rule - public final BaseSelectorRule selectorRule = new BaseSelectorRule(); - - @Test - public void testCase1() { - - - // Configure the selector - MySelector s = new MySelector(); - s.addParam("key1", "value1"); - s.addParam("key2", "value2"); - s.setXX(true); - s.setYY("a value"); - - // do the tests - assertEquals("FTTTTTTTT", selectorRule.selectionString(s)); - } -} - </pre> - As an example of an error JUnit could log<pre> - [junit] FAILED - [junit] Error for files: <font color=blue>.;copy.filterset.filtered;tar/gz/asf-logo.gif.tar.gz</font> - [junit] expected:<<font color=blue>FTTTFTTTF...</font>> but was:<TTTTTTTTT...> - [junit] junit.framework.ComparisonFailure: Error for files: .;copy.filterset.filtered;tar/gz/asf-logo.gif.tar.gz - [junit] expected:<FTTTFTTTF...> but was:<TTTTTTTTT...> - [junit] at junit.framework.Assert.assertEquals(Assert.java:81) - [junit] at org.apache.tools.ant.types.selectors.BaseSelectorTest.performTest(BaseSelectorTest.java:194) - </pre></p> - - <p>Described above the test class should provide a <tt>getInstance()</tt> - method. But that isn't used here. The used <tt>getSelector()</tt> method is - implemented in the base class and gives an instance of an Ant Project to - the selector. This is usually done inside normal build file runs, but not - inside this special environment, so this method gives the selector the - ability to use its own Project object (<tt>getProject()</tt>), for example - for logging.</p> - - - <h3>Logging</h3> - - <p>During development and maybe later you sometimes need the output of information. - Therefore Logging is needed. Because the selector extends BaseExtendSelector or directly - BaseSelector it is an Ant <tt>DataType</tt> and therefore a <tt>ProjectComponent</tt>. <br> - That means that you have access to the project object and its logging capability. - <tt>ProjectComponent</tt> itself provides <i>log</i> methods which will do the - access to the project instance. Logging is therefore done simply with: - <pre> - log( "message" ); - </pre> - or - <pre> - log( "message" , loglevel ); - </pre> - where the <tt>loglevel</tt> is one of the values <ul> - <li> org.apache.tools.ant.Project.MSG_ERR </li> - <li> org.apache.tools.ant.Project.MSG_WARN </li> - <li> org.apache.tools.ant.Project.MSG_INFO (= default) </li> - <li> org.apache.tools.ant.Project.MSG_VERBOSE </li> - <li> org.apache.tools.ant.Project.MSG_DEBUG </li> - </ul> - </p> - - - </body> - -</html> |