public function setPatchFile(PhingFile $file)
    {
        if (!$file->exists()) {
            throw new BuildException('patchfile ' . $file . " doesn't exist", $this->getLocation());
        }
        $this->cmd->createArgument()->setValue('-i');
        $this->cmd->createArgument()->setFile($file);
        $this->havePatchFile = true;
    }