我在位于/data/data.my.package.app/files/file.xml
的现有xml文件中添加了节点,我只想保存文件,但我没有发现。
我试过在另一篇文章中看到的这个功能:
private void save(Document newDoc) throws Exception{
Transformer transformer = TransformerFactory.newInstance().newTransformer();
transformer.setOutputProperty(OutputKeys.INDENT, "yes");
StreamResult result = new StreamResult(new File(context.getFilesDir().getAbsolutePath() + "/file.xml"));
Source source = new DOMSource(newDoc);
transformer.transform(source, result);
}
但是我在tranformer.transform()
上得到一个空指针异常......这就是我初始化我的Document文件的方法。
FileInputStream is = new FileInputStream(context.getFilesDir().getAbsolutePath() + "/file.xml");
DocumentBuilderFactory dbFactory = DocumentBuilderFactory.newInstance();
DocumentBuilder dBuilder = dbFactory.newDocumentBuilder();
Document doc = dBuilder.parse(is);
非常感谢你帮助A.D.
该文件不能是新的。必须已经存在:
StreamResult result =
new StreamResult(new File(context.getFilesDir().getAbsolutePath() + "/file.xml"));
对我来说这项工作:
//save the doc as string in a text file with the same name (extension .xml)
save(this, body, dir, FILENAME_XML);
//apply the transformer
TransformerFactory transformerFactory = TransformerFactory.newInstance();
Transformer transformer = transformerFactory_p.newTransformer();
DOMSource source = new DOMSource(doc);
StreamResult result = new StreamResult(
new File(dir+File.separator+FILENAME_XML));
transformer.transform(source, result);
生成文件xml。