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                      <meta name="author" value="Peter Donald">
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      <title>Apache Myrmidon - Writing a task</title>
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          <td valign="bottom"><div align="right"><b><font size="+3" color="#525D76">Apache Myrmidon</font></b></div></td>
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                <p><strong>Myrmidon</strong></p>
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          <li>      <a href="./index.html">Introduction</a>
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          <li>      <a href="./getinvolved.html">Get Involved</a>
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          <li>      <a href="./user.html">Building Myrmidon</a>
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      <p><strong>Extending Ant</strong></p>
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          <li>      <a href="./task.html">Task Writers HOWTO</a>
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          <li>      <a href="./classloader.html">ClassLoader HOWTO</a>
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        <a name="Writing a Task"><strong>Writing a Task</strong></a>
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                        <p>In ant1 it was very easy to write your own task. In Ant2 we plan 
to make it even easier. To write a basic task simply follow the following
formula.</p>
                                <ol>
  <li>
    Create a Java class that extends 
    <code>org.apache.myrmidon.api.AbstractTask</code>
  </li>
  <li>
    For each attribute, write a setter method. The setter method 
    must be a public void method that takes a single argument. The name 
    of the method must begin with "set", followed by the attribute name, with 
    the first character of the name in uppercase, and the rest in lowercase. 
    The type of the attribute can be:
    <ul>
      <li>String</li>
      <li>
        Any primitive type - they are converted for you from their 
        String-representation in the buildfile
      </li>
      <li>
        File - the string representation will be interpreted relative to 
        the project's basedir.
      </li>
    </ul>
  </li>
  <li>
    For each nested element create a public void method that takes a single 
    argument. The name of the method must begin with "add", followed by the 
    attribute name, with the first character of the name in uppercase, and 
    the rest in lowercase. The type of the parameter is an object with a 
    no-arguement constructor. It is configured in exactly the same was a 
    task is configured (via setters and adders) and then added to the task.
  </li>
  <li>
    Write a public void method named "execute" with no arguments that 
    throws a TaskException. This is the method called to do the 
    actual work of the task.
  </li>
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        <a name="A Basic Example"><strong>A Basic Example</strong></a>
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      <blockquote>
                        <p>So a basic task that has one attribute named "message" and just prints 
out this message is as simple as;</p>
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package org.realityforge.tasks;

import org.apache.myrmidon.api.AbstractTask;
import org.apache.myrmidon.api.TaskException;

public class SystemOutPrinterTask 
    extends Task 
{
    private String m_message;

    // The setter for the &quot;message&quot; attribute
    public void setMessage( final String message )
    {
        m_message = message;
    }

    // The method executing the task
    public void execute() 
        throws TaskException 
    {
        System.out.println( m_message );
    }
}
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                                <p>To use this task you <em>could</em> create a library but instead we will 
just use &lt;taskdef&gt; to define the task. An example usage would be;</p>
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&lt;?xml version=&quot;1.0&quot;?&gt;

&lt;project version=&quot;2.0&quot;&gt;

  &lt;target name=&quot;main&quot;&gt;
    &lt;taskdef name=&quot;printer&quot; 
             classname=&quot;org.realityforge.tasks.SystemOutPrinterTask&quot;
             classpath=&quot;build/classes&quot;/&gt;

    &lt;printer message=&quot;Hello World!&quot;/&gt;
  &lt;/target&gt;
&lt;/project&gt;


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