dom4j 改变XML声明和编码格式

dom4j 改变XML编码

Element rootElement = document.addElement("data");
document.setXMLEncoding("GBK");	//默认utf-8
...

使用document.setXMLEncoding这样设置而生成的xml文件仍然是utf-8编码。

需要使用OutputFormat设置输出文件编码格式。

 public static void writeXMLFile(Document document,File file,String Encoding){
   try {
          OutputFormat format = OutputFormat.createPrettyPrint();//美化输出 不想美化可以使用new OutputFormat();
          format.setEncoding(Encoding.toUpperCase());
          OutputStream out = new FileOutputStream(file);
          XMLWriter writer = new XMLWriter(out,format);
          writer.write(document);
          writer.close();
        }catch (IOException e) {
          e.printStackTrace();
        }	

使用OutputFormat，可以设置xml输出文件编码，并且xml文件声明处也会跟着改变。

引用别人答案：解释document.setXMLEncoding和format.setEncoding设置编码的区别

public class TestXML{
   @Test
    public void test() throws IOException{
        Document doc = new DefaultDocument();
        doc.addElement("root");
        // 这里打印出来是默认的utf-8
        System.out.println(doc.asXML());
        doc.setXMLEncoding("utf-16");
        // 这里打印出来是修改后的utf-16
        System.out.println(doc.asXML());
        // 这里没有设置编码格式默认保存的是utf-8，看一下dom4j的源码就知道了
        saveXML(doc, "D:\temp\test\test1.xml", null);
        // 这里设置了所以保存以后编码格式是big5
        saveXML(doc, "D:\temp\test\test2.xml", "big5");
    }
    private void saveXML(Document doc, String filePath, String encode) throws IOException{
        OutputFormat format = new OutputFormat();
        if (null != encode){
            format.setEncoding(encode.toUpperCase());
        }
        XMLWriter xmlWriter = new XMLWriter(new FileOutputStream(filePath),format);
        xmlWriter.write(doc);
        xmlWriter.flush();
        xmlWriter.close();
    }
}

上面代码出自此处。

最后要说一下：

XMLWriter可以传入OutputStream或者Writer
	XMLWriter writer = new XMLWriter(OutputStream, OutputFormat);
	XMLWriter writer = new XMLWriter(Writer, OutputFormat);
最初试着传入了new FileWriter(file),如下
try {
		XMLWriter writer = new XMLWriter(new FileWriter(f), format);
		writer.write(document);
		writer.close();
		result = fileName;
	} catch (IOException e) { // TODO Auto-generated catch block
		e.printStackTrace();
	}	
但是得到的结果并不对。修改为如下后，结果正确。
			try {
				OutputFormat format = OutputFormat.createPrettyPrint();
				XMLWriter xmlWriter = new XMLWriter(new FileOutputStream(f), format);
				xmlWriter.write(document);
				xmlWriter.flush();
				xmlWriter.close();
				result = fileName;
			} catch (IOException e) { // TODO Auto-generated catch block
				e.printStackTrace();
				LOG.error("trans for XML error:", e);
			}

记录。

相关链接：
http://www.iteye.com/problems/64178
http://bbs.csdn.net/topics/370057777
http://liuchunqing2001.blog.163.com/blog/static/3082291201382911214196/
http://lavasoft.blog.51cto.com/62575/235272
http://www.educity.cn/wenda/105197.html
http://www.blogjava.net/i369/articles/154264.html
http://bbs.csdn.net/topics/290027113
http://developer.51cto.com/art/200903/117512.htm
http://pridesnow.iteye.com/blog/561958
http://blog.csdn.net/chenghui0317/article/details/11486271
Java创建xml文档笔记(DOM,DOM4J)
http://www.cnblogs.com/lanxuezaipiao/archive/2013/05/17/3082949.html