Creating an ear-File with ant - ant

Question

I am new to ant i referred many sites , i need to build.xml for my project which consists
of two modules i have application.xml file which represents corresponding war file
so my question is it sufficient to add the application.xml file
<ear destfile="${dist.dir}/${ant.project.name}.ear" appxml="${conf.dir}/application.xml">
<metainf dir="${build.dir}/META-INF"/>
<fileset dir="${dist.dir}" includes="*.jar,*.war"/>
</ear>
whether this will refer the corresponding war files or i need to compile the whole scenario please let me know. how solve this.

Answer 1

I'm not 100% sure what you're asking.
In order to use the <ear> task, you already need to have compiled the required jars and wars.
If those jars and wars have already been built, you simply refer to them in your <ear> task as you did in your example. The application.xml must already exist before you build your ear. The application.xml doesn't build the jars and wars, you have to do that.
If you haven't already built the wars and jars, you need to do that first. A general outline of a build.xml looks something like this:
<project name="foo" basedir="." default="package">
<!-- Some standard properties you've defined -->
<property name="target.dir" value="${basedir}/target"/>
<property name="xxx" value="yyy"/>
<property name="xxx" value="yyy"/>
<property name="xxx" value="yyy"/>
<!-- Compile properties that allow overrides -->
<property name="javac.nowarn" value="false"/>
<property name="javac.listfiles" value="false"/>
<property name="javac.srcdir" value="source"/>
<property name="javac.distdir" value="${target.dir}/classes"/>
<target name="clean"
description="cleans everything nice and shiny">
<delete dir="${target.dir}"/>
</target>
<target name="compile"
description="Compiles everything">
<mkdir dir="${javac.distdir}"/>
<javac srcdir="${javac.srcdir}"
destdir="${javac.destdir}"
[...]
[...]/>
</target>
<target name="package.jar"
depends="compile"
description="Package jarfile">
<jar destfile="${target.dir}/jarname.jar"
[...]
[...]/>
</target>
<target name="package.jar2"
depends="compile"
description="Package jarfile">
<jar destfile="${target.dir}/jarname2.jar"
[...]
[...]/>
</target>
<target name="package.war"
depends="compile"
description="Package jarfile">
<war destfile="${target.dir}/jarname.jar"
[...]
[...]/>
</target>
<target name="package"
depends="package.jar"
description="Make the ear">
<ear destfile="${target.dir}/earfile.ear"
[...]/>
</target>
</project>
Basically, it consists of a bunch of targets and each target does one task. You can have targets depend upon other targets. For example, this particular build.xml will automatically run the package task. The package task depends upon the package.jar task which depends upon the compile task. Thus, the build.xml file will first call compile, then package.jar, then package.
The important thing to remember is that you don't specify the order of the events. You let Ant figure that out, and you let Ant figure out what you need to do. Let's say you've modified a java source file. Ant knows that it has to recompile only that one file. It also knows that it might have to rebuild the jarfile that contains that classfile. And, it then knows it has to rebuild the ear. Most tasks can figure it out on their own, and you don't do a clean for each build. (You notice that the clean target isn't called by package or compile. You have to call it manually).
The only other thing I recommend is that you try to keep your work area clean. Any files you create should be put into the ${target.dir} directory. That way, when you do a clean, you only have to delete that one directory.
I hope this answer your question.