Java XML输出 - 子项的正确缩进

Question

我想将一些简单的数据模型序列化为xml,我一直在使用标准的java.org.w3c相关代码(见下文),缩进比没有"OutputKeys.INDENT"好,但还有一点点剩下的东西 - 适合儿童元素的缩进.

我知道之前已经在stackoverflow上询问过,但是这个配置对我来说不起作用,这是我正在使用的代码:

        DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
        DocumentBuilder builder = factory.newDocumentBuilder();
        Document doc = builder.newDocument();

        doc = addItemsToDocument(doc);
        // The addItemsToDocument method adds childElements to the document.

        TransformerFactory transformerFactory = TransformerFactory.newInstance();
        transformerFactory.setAttribute("indent-number", new Integer(4));
        // switching to setAttribute("indent-number", 4); doesn't help

        Transformer transformer = transformerFactory.newTransformer();
        transformer.setOutputProperty(OutputKeys.METHOD, "xml");
        transformer.setOutputProperty(OutputKeys.INDENT, "yes");

         DOMSource source = new DOMSource(doc);
       StreamResult result = new StreamResult(outFile);
        // outFile is a regular File outFile = new File("some/path/foo.xml");

        transformer.transform(source, result);

产生的输出是:

<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<stuffcontainer>
<stuff description="something" duration="240" title="abc">
<otherstuff />
</stuff>
</stuffcontainer>

而我想要它(为了更清晰),如:

<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<stuffcontainer>
  <stuff description="something" duration="240" title="abc">
    <otherstuff />
  </stuff>
</stuffcontainer>

我只是想知道是否有这样做的方法,使它适当缩进为子元素.

先感谢您 !
复活节快乐编码:-)!

Answer 1

如果您使用的Transformer实现是Xalan-J,那么您应该能够使用:

transformer.setOutputProperty(
   "{http://xml.apache.org/xslt}indent-amount", "5");

另见:http://xml.apache.org/xalan-j/usagepatterns.html