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diff --git a/framework/src/ant/apache-ant-1.9.6/manual/Tasks/depend.html b/framework/src/ant/apache-ant-1.9.6/manual/Tasks/depend.html deleted file mode 100644 index a0943197..00000000 --- a/framework/src/ant/apache-ant-1.9.6/manual/Tasks/depend.html +++ /dev/null @@ -1,216 +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>Depend Task</title> -</head> - -<body> - -<h2>Depend</h2> - -A task to manage Java class file dependencies. - -<h3>Description</h3> - -<p> -The depend task works by determining which classes are out of date with -respect to their source and then removing the class files of any other -classes which depend on the out-of-date classes. -</p> - -<p> To determine the class dependencies, the depend task analyzes the class -files of all class files passed to it. Depend does not parse your source code in -any way but relies upon the class references encoded into the class files by the -compiler. This is generally faster than parsing the Java source.</p> - -<p> -To learn more about how this information is obtained from the class files, -please refer to <a href="http://docs.oracle.com/javase/specs/">the Java -Virtual Machine Specification</a> -</p> - -<p> Since a class' dependencies only change when the class itself changes, the -depend task is able to cache dependency information. Only those class files -which have changed will have their dependency information re-analysed. Note that -if you change a class' dependencies by changing the source, it will be -recompiled anyway. You can examine the dependency files created to understand -the dependencies of your classes. Please do not rely, however, on the format of -the information, as it may change in a later release. </p> - -<p> Once depend discovers all of the class dependencies, it "inverts" -this relation to determine, for each class, which other classes are dependent -upon it. This "affects" list is used to discover which classes are -invalidated by the out of date class. The class files of the invalidated -classes are removed, triggering the compilation of the affected classes. </p> - -<p> The depend task supports an attribute, "closure" which controls -whether depend will only consider direct class-class relationships or whether it -will also consider transitive, indirect relationships. For example, say there -are three classes, A, which depends on B, which in-turn depend on C. Now say -that class C is out of date. Without closure, only class B would be removed by -depend. With closure set, class A would also be removed. Normally direct -relationships are sufficient - it is unusual for a class to depend on another -without having a direct relationship. With closure set, you will notice that -depend typically removes far more class files. </p> - -<p>The classpath attribute for <code><depend></code> is optional. If it is present, -depend will check class dependencies against classes and jars on this classpath. -Any classes which depend on an element from this classpath and which are older -than that element will be deleted. A typical example where you would use this -facility would be where you are building a utility jar and want to make sure -classes which are out of date with respect to this jar are rebuilt. You should -<b>not</b> include jars in this classpath which you do not expect to change, -such as the JDK runtime jar or third party jars, since doing so will just slow -down the dependency check. This means that if you do use a classpath for the -depend task it may be different from the classpath necessary to actually -compile your code.</p> - -<h3>Performance</h3> - -<p> The performance of the depend task is dependent on a -number of factors such as class relationship complexity and how many class files -are out of date. The decision about whether it is cheaper to just recompile all -classes or to use the depend task will depend on the size of your project and -how interrelated your classes are. </p> - - -<h3>Limitations</h3> - -<p> There are some source dependencies which depend will not detect. </p> - -<ul> -<li>If the Java compiler optimizes away a class relationship, - there can be a source dependency without a class dependency. </li> - -<li>Non public classes cause two problems. Firstly depend cannot relate - the class file to a source file. In the future this may be addressed - using the source file attribute in the classfile. Secondly, neither - depend nor the compiler tasks can detect when a non public class is - missing. Inner classes are handled by the depend task.</li> -</ul> - -The most obvious example of these limitations is that the task can't tell -which classes to recompile when a constant primitive data type exported -by other classes is changed. For example, a change in the definition of -something like -<pre> -public final class Constants { - public final static boolean DEBUG=false; -} -</pre> will not be picked up by other classes. - -<h3>Parameters</h3> -<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">srcDir</td> - <td valign="top">This is the directory where the source exists. depend -will examine this to determine which classes are out of date. If you use multiple -source directories you can pass this attribute a path of source directories.</td> - <td valign="top" align="center">Yes</td> - </tr> - <tr> - <td valign="top">destDir</td> - <td valign="top">This is the root directory of the class files which -will be analysed. If this is not present, the srcdir is used.</td> - <td valign="top" align="center">No</td> - </tr> - <tr> - <td valign="top">cache</td> - <td valign="top">This is a directory in which depend can store and -retrieve dependency information. If this is not present, depend will not -use a cache </td> - <td valign="top" align="center">No</td> - </tr> - <tr> - <td valign="top">closure</td> - <td valign="top">This attribute controls whether depend only removes -classes which directly depend on out of date classes. If this is set to true, -depend will traverse the class dependency graph deleting all affected -classes. Defaults to false</td> - <td valign="top" align="center">No</td> - </tr> - <tr> - <td valign="top">dump</td> - <td valign="top">If true the dependency information will be written to the debug level log - </td> - <td valign="top" align="center">No</td> - </tr> - <tr> - <td valign="top">classpath</td> - <td valign="top">The classpath containing jars and classes for which <code><depend></code> should also - check dependencies</td> - <td valign="top" align="center">No</td> - </tr> - <tr> - <td valign="top">warnOnRmiStubs</td> - <td valign="top">Flag to disable warnings about files that look like rmic generated stub/skeleton - classes, and which have no .java source. Useful when doing rmi development. </td> - <td valign="top" align="center">No, default=true</td> - </tr> -</table> - -<h3>Parameters specified as nested elements</h3> -<p>The <code>depend</code> task's <code>classpath</code> attribute is a -<a href="../using.html#path">PATH-like structure</a> and can also be set -via a nested <code><classpath></code> element.</p> - -<p>Additionally, -this task forms an implicit -<a href="../Types/fileset.html">FileSet</a> -and supports most attributes of -<code><fileset></code> (<code>dir</code> becomes <code>srcdir</code>), -as well as the nested <code><include></code>, -<code><exclude></code>, and <code><patternset></code> elements. - -<h3>Examples</h3> -<pre><depend srcdir="${java.dir}" - destdir="${build.classes}" - cache="depcache" - closure="yes"/></pre> - -<p>removes any classes in the <code>${build.classes}</code> directory -that depend on out-of-date classes. Classes are considered out-of-date with -respect to the source in the <code>${java.dir}</code> directory, using the same -mechanism as the <code><javac></code> task. In this example, the -<code><depend></code> task caches its dependency -information in the <code>depcache</code> directory. </p> - -<pre> -<depend srcdir="${java.dir}" destdir="${build.classes}" - cache="depcache" closure="yes"> - <include name="**/*.java"/> - <excludesfile name="${java.dir}/build_excludes"/> -</depend> -</pre> -<p>does the same as the previous example, but explicitly includes all -<code>.java</code> files, except those that match the list given -in <code>${java.dir}/build_excludes</code>.</p> - - - -</body> -</html> - |