java - 如何使用 JDOM 将独立的 ="no"添加到文件？

Question

我找到了here如何将 XML 文档的打印输出重写到 Eclipse 控制台，以便它包含 standalone = "no"，但是如何编写 standalone = "no"到一个文件？我尝试将相同的文档写入文件，但它仍然不会打印standalone =“no”。换句话说，当我尝试写入文件时，重写的方法不起作用。

写入文件时是否应该重写其他方法？这里有什么问题吗？

private static void writeXML() {

try {

Document doc = new Document();

Element theRoot = new Element("tvshows");
doc.setRootElement(theRoot);

Element show = new Element("show");
Element name = new Element("name");
name.setAttribute("show_id", "show_001");

name.addContent(new Text("Life on Mars"));

Element network = new Element("network");
network.setAttribute("country", "US");

network.addContent(new Text("ABC"));

show.addContent(name);
show.addContent(network);

theRoot.addContent(show);

//-----------------------------

Element show2 = new Element("show");
Element name2 = new Element("name");
name2.setAttribute("show_id", "show_002");

name2.addContent(new Text("Life on Mars"));

Element network2 = new Element("network");
network2.setAttribute("country", "UK");

network2.addContent(new Text("BBC"));

show2.addContent(name2);
show2.addContent(network2);

theRoot.addContent(show2);

XMLOutputter xmlOutput = new XMLOutputter(Format.getPrettyFormat(), XMLOUTPUT);
//xmlOutput.output(doc, System.out);

xmlOutput.output(doc, new FileOutputStream(new File("./src/jdomMade.xml")));

System.out.println("The file has been written");

}
catch (Exception ex){
    ex.printStackTrace();
}


}

public static final XMLOutputProcessor XMLOUTPUT = new AbstractXMLOutputProcessor() {
@Override
protected void printDeclaration(final Writer out, final FormatStack fstack) throws IOException {
    write(out, "<?xml version=\"1.0\" encoding=\"utf-8\" standalone=\"no\"?> ");
    write(out, fstack.getLineSeparator());
}

};

Answer 1

你的代码撒谎了;-)

xmlOutput.output(doc, new FileOutputStream(new File("./src/jdomMade.xml")));

System.out.println("The file has been written");

println 表示文件已写入，但实际上尚未写入。

仅当文件被刷新并关闭时才会写入该文件。你不应该这样做。

您应该在代码中添加 try-with-resources:

try (FileOutputStream fos = new FileOutputStream(new File("./src/jdomMade.xml"))) {
    xmlOutput.output(doc, fos);
}

System.out.println("The file has been written");