如何将符合xml规范的String转化为XML文档中的element对象

如何将符合xml规范的String转化为XML文档中的element对象：

/** * 字符串转化为XML对象并加入到XML中的某一个节点下 * @throws DocumentException */public void stringToXml() throws DocumentException{SAXReader saxReader = new SAXReader();Document doc;try {doc = saxReader.read(new ByteArrayInputStream(xmlStr.getBytes("UTF-8")));if (doc!=null){            Element element=doc.getRootElement(); SAXReader saxReader1 = new SAXReader();Document document1 = saxReader1.read(fileName);Element element1 = (Element)document1.selectSingleNode("//template");element1.add(element);writeXML(document1);    }} catch (UnsupportedEncodingException e) {e.printStackTrace();}}/** * 写XML * @param doc */private void writeXML(Document doc){        OutputFormat of = OutputFormat.createPrettyPrint();        of.setEncoding("utf-8");        FileOutputStream fos = null;        XMLWriter xmlout = null;        String lockfilename = fileName + ".lock";        MessageLock lock = new MessageLock(lockfilename);        try{        if(lock.lock()) {        fos = new FileOutputStream(this.fileName);                xmlout = new XMLWriter(new OutputStreamWriter(fos, "utf-8"), of);                xmlout.write(doc);                xmlout.flush();        }        }catch (Exception ex){        log.error("-->writeXml",ex);        }finally{        lock.unlock();            if (fos != null){                try{                fos.close();                }catch (IOException ex1){                log.error("-->writeXml",ex1);                }            }            if (xmlout != null){                try{                    xmlout.close();                }catch (IOException ex2){                log.error("-->writeXml",ex2);                }            }        }    }

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