public  void addSrcfilelist(FileList fl) 
{
        createSources().add(fl);
}

Add a list of source files.

 public  void addSrcfileset(FileSet fs) 
{
        createSources().add(fs);
}

Add a set of source files.

 public  void addTargetfilelist(FileList fl) 
{
        createTargets().add(fl);
}

Add a list of target files.

 public  void addTargetfileset(FileSet fs) 
{
        createTargets().add(new HideMissingBasedir(fs));
}

Add a set of target files.

 public synchronized Union createSources() 
{
                  
        sources = (sources == null) ? new Union() : sources;
        return sources;
}

Create a nested sources element.

 public synchronized Path createTargets() 
{
        targets = (targets == null) ? new Path(getProject()) : targets;
        return targets;
}

Create a nested targets element.

 public  void execute() throws BuildException 
{
        if (sources == null) {
          throw new BuildException(
              "At least one set of source resources must be specified");
        }
        if (targets == null) {
          throw new BuildException(
              "At least one set of target files must be specified");
        }
        //no sources = nothing to compare; no targets = nothing to delete:
        if (sources.size()  > 0 && targets.size()  > 0 && !uptodate(sources, targets)) {
           log("Deleting all target files.", Project.MSG_VERBOSE);
           Delete delete = new Delete();
           delete.bindToOwner(this);
           delete.add(targets);
           delete.perform();
        }
}

Execute the task.