将简单的XML文档从URL解析为String变量

Question

I am attempting to read XML from a server on http://localhost:8000 , into a string variable.

The layout of the XML document is very simple, and when directing to http://localhost:8000 , the following is displayed:

<result>Hello World</result>

Is there a simple way to parse this into a String variable from the localhost URL, so that for example, if I was to run:

System.out.println(XMLVariable) 

(where XMLVariable is the string variable in which the content was stored in) that the output to the command line would simply be "Hello World"?

Answer 1

You need to parse the response from the server into an XML data structure of some sort.

The easiest way that I'm aware of (in Java) to do that is to use dom4j .

It can be as simple as this...

SAXReader reader = new SAXReader();
Document document = reader.read("http://localhost:8000/");
System.out.println(document.getText());

Answer 2

You can use StAX for parsing the response:

private Optional<String> extractResultValue(String xml) throws XMLStreamException {
    final XMLInputFactory factory = XMLInputFactory.newInstance();
    final XMLEventReader reader = factory.createXMLEventReader(new StringReader(xml));
    while (reader.hasNext()) {
        XMLEvent event = reader.nextEvent();
        if (event.isCharacters()) {
            return Optional.ofNullable(event.asCharacters().getData());
        }
    }
    return Optional.empty();
}

Example call:

extractResultValue("<Your data from server>")
extractResultValue("<result>Hello World</result>") // Optional[Hello World]
extractResultValue("<result></result>") // Optional.empty
extractResultValue("<test>value</test>") // Optional[value]