XML格式化问题

            TransformerFactory tFactory = TransformerFactory.newInstance();
            Transformer transformer = tFactory.newTransformer();
            transformer.setOutputProperty(OutputKeys.INDENT, "yes");
            DOMSource source = new DOMSource(doc);
            StringBuffer writeFilePath = new StringBuffer(readFilePath);
            writeFilePath.insert(writeFilePath.indexOf("."), "_" + language);
            StreamResult result = new StreamResult(writeFilePath.toString());
            transformer.transform(source, result);

以上代码生成的XML文件格式如下，想将其格式化，怎么操作呀？生成的XML中空行是由于删除一个节点，如何去掉这个空行呢？最后面两个param是新增的，跟别的也不对齐，请问怎么操作呢？？？？
<Cond name="Cond1">
  <param name="a">aa </param>
  <param name="b">RequestInfo </param>
  <param name="c">1 </param>
  <param name="d">null </param>
  <param name="g">null </param>
  <param name="e">hhhhhhhhhhhhhh