public  void addFileset(FileSet set) 
{
        fileSets.add(set);
}

 protected  void assertFiles(String[] files) 
{
        if (files.length == 0)
            throw new BuildException(_loc.get("no-filesets").getMessage());
}

Helper method to throw a standard exception if the task is not given any files to execute on. Implementations might call this method as the first step in #executeOn to validate that they are given files to work on.

 public Path createClasspath() 
{
        if (classpath == null)
            classpath = new Path(project);
        return classpath.createPath();
}

 public Object createConfig() 
{
        return getConfiguration();
}

 public  void execute() throws BuildException 
{
        // if the user didn't supply a conf file, load the default
        if (_conf == null)
            _conf = newConfiguration();
        if (_conf.getPropertiesResource() == null) {
            ConfigurationProvider cp = ProductDerivations.loadDefaults
                ((ClassLoader) AccessController.doPrivileged(
                    J2DoPrivHelper.getClassLoaderAction(_conf.getClass())));
            if (cp != null)
                cp.setInto(_conf);
        }
        String[] files = getFiles();
        try {
            executeOn(files);
        } catch (Throwable e) {
            e.printStackTrace();
            if (haltOnError)
                throw new BuildException(e);
        } finally {
            _conf.close();
            _conf = null;
        }
}

 abstract protected  void executeOn(String[] files) throws Exception
Perform the task action on the given files.

 protected ClassLoader getClassLoader() 
{
        if (_cl != null)
            return _cl;
        if (classpath != null)
            _cl = new AntClassLoader(project, classpath, useParent);
        else
            _cl = new AntClassLoader(project.getCoreLoader(), project,
                new Path(project), useParent);
        _cl.setIsolated(isolate);
        return _cl;
}

Return the classloader to use.

 public Configuration getConfiguration() 
{
        if (_conf == null)
            _conf = newConfiguration();
        return _conf;
}

The task configuration.

 abstract protected ConfigurationImpl newConfiguration()
Implement this method to return a configuration object for the
product in use.

 public  void setClasspath(Path classPath) 
{
        createClasspath().append(classPath);
}

 public  void setHaltOnError(boolean haltOnError) 
{
                   
        this.haltOnError = haltOnError;
}

Set whether we want the task to ignore all errors.

 public  void setIsolate(boolean isolate) 
{
        this.isolate = isolate;
}

Whether we want the ClassLoader to be isolated from all other ClassLoaders

 public  void setUseParentClassloader(boolean useParent) 
{
        this.useParent = useParent;
}

Whether we want to delegate to the parent ClassLoader for resolveing classes. This may "taint" classes.