Apache Myrmidon

Myrmidon

User Guide

Extending Ant

Container Design

My First Task

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.

  1. Create a Java class that extends org.apache.myrmidon.api.AbstractTask
  2. 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:
    • String
    • Any primitive type - they are converted for you from their String-representation in the buildfile
    • File - the string representation will be interpreted relative to the project's basedir.
  3. 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.
  4. 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.
A Basic Example

So a basic task that has one attribute named "message" and just prints out this message is as simple as;

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 "message" 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 );
    }
}

To use this task you could create a library but instead we will just use <taskdef> to define the task. An example usage would be;



<?xml version="1.0"?>

<project version="2.0">

  <target name="main">
    <taskdef name="printer"
             classname="org.realityforge.tasks.SystemOutPrinterTask"
             classpath="build/classes"/>

    <printer message="Hello World!"/>
  </target>
</project>



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