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diff --git a/framework/src/ant/apache-ant-1.9.6/manual/antexternal.html b/framework/src/ant/apache-ant-1.9.6/manual/antexternal.html new file mode 100644 index 00000000..02d2f7b5 --- /dev/null +++ b/framework/src/ant/apache-ant-1.9.6/manual/antexternal.html @@ -0,0 +1,160 @@ +<!-- + 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. +--> +<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> +<html> +<head> +<meta http-equiv="Content-Language" content="en-us"> +<link rel="stylesheet" type="text/css" href="stylesheets/style.css"> +<title>InputHandler</title> +</head> + +<body> +<h1>Using Apache Ant™ Tasks Outside of Ant</h1> + +<h2>Rationale</h2> + +<p>Apache Ant provides a rich set of tasks for buildfile creators and +administrators. But what about programmers? Can the functionality +provided by Ant tasks be used in java programs?</p> + +<p>Yes, and its quite easy. Before getting into the details, however, +we should mention the pros and cons of this approach: + +<h3>Pros</h3> + +<table cellpadding="0" margin="0" border="1"> +<tr> +<td><b>Robust</b></td> +<td> +Ant tasks are very robust. They have been banged on by many people. +Ant tasks have been used in many different contexts, and have +therefore been instrumented to take care of a great many boundary +conditions and potentially obscure errors. +</td> +</tr> +<tr> +<td><b>Cross Platform</b></td> +<td> +Ant tasks are cross platform. They have been tested on all of the +volume platforms, and several rather unusual ones (Netware and OS/390, to +name a few). +</td> +</tr> +<tr> +<td><b>Community Support</b></td> +<td> +Using Ant tasks means you have less of your own code to support. Ant +code is supported by the entire Apache Ant community. +</td> +</tr> +</table> + +<h3>Cons</h3> + +<table cellpadding="0" margin="0" border="1"> +<tr> +<td><b>Dependency on Ant Libraries</b></td> +<td> +Obviously, if you use an Ant task in your code, you will have to add +"ant.jar" to your path. Of course, you could use a code optimizer to +remove the unnecessary classes, but you will still probably require a +chunk of the Ant core. +</td> +</tr> +<tr> +<td><b>Loss of Flexibility</b></td> +<td> +At some point, if you find yourself having to modify the Ant code, it +probably makes more sense to "roll your own." Of course, you can +still steal some code snippets and good ideas. This is the beauty of +open source! +</td> +</tr> +</table> + + +<h2>Example</h2> + +<p>Let's say you want to unzip a zip file programmatically from java +into a certain directory. Of course you could write your own routine +to do this, but why not use the Ant task that has already been written?</p> + +<p>In my example, I wanted to be able to unzip a file from within an +XSLT Transformation. XSLT Transformers can be extended by plugging in +static methods in java. I therefore need a function something like +this:</p> + +<pre> +/** + * Unzip a zip file into a given directory. + * + * @param zipFilepath A pathname representing a local zip file + * @param destinationDir where to unzip the archive to + */ + static public void unzip(String zipFilepath, String destinationDir) +</pre> + +<p> +The Ant task to perform this function is +<code>org.apache.tools.ant.taskdefs.Expand</code>. All we have to do +is create a dummy Ant <code>Project</code> and <code>Target</code>, +set the <code>Task</code> parameters that would normally be set in a +buildfile, and call <code>execute()</code>.</p> + +<p>First, let's make sure we have the proper includes:</p> + +<pre> +import org.apache.tools.ant.Project; +import org.apache.tools.ant.Target; +import org.apache.tools.ant.taskdefs.Expand; +import java.io.File; +</pre> + +<p>The function call is actually quite simple:</p> + +<pre> +static public void unzip(String zipFilepath, String destinationDir) { + + final class Expander extends Expand { + public Expander() { + project = new Project(); + project.init(); + taskType = "unzip"; + taskName = "unzip"; + target = new Target(); + } + } + Expander expander = new Expander(); + expander.setSrc(new File(zipfile)); + expander.setDest(new File(destdir)); + expander.execute(); +</pre> + +<p>In actual practice, you will probably want to add your own error +handling code and you may not want to use a local inner class. +However, the point of the example is to show how an Ant task can be +called programmatically in relatively few lines of code.</p> + +<p>The question you are probably asking yourself at this point is: +<i>How would I know which classes and methods have to be called in +order to set up a dummy Project and Target?</i> The answer is: you +don't. Ultimately, you have to be willing to get your feet wet and +read the source code. The above example is merely designed to whet +your appetite and get you started. Go for it!</p> + + +</html> |