从Java中的xml中提取特定元素

Question

How can I extract a block of data from an XML file by element name, or delete all content of an XML file except for one element and all its child nodes?

I am new to Java, I have tried with XPath but did not get what I wanted to have.

Answer 1

You do not to delete anything. By XPath you need to transverse to the element you needed. Another thing is Xpath has nothing to do with the language you are using for scripting. It can be java, python, C#, ruby etc.

To learn more about Xpath refer below link :-

http://www.w3schools.com/xsl/xpath_intro.asp

Hope it will help you :)

Answer 2

test .... ....

here is the sample code to get ID element content expressions public static final String IdExpr = "/NameDefinition/@Id";

String evaluateXML(String file, String IdExpr) {

Stringres= null;
try {
    FileInputStream fis = new FileInputStream(new File(file));

    DocumentBuilderFactory builderFactory = DocumentBuilderFactory
        .newInstance();
    DocumentBuilder builder = builderFactory.newDocumentBuilder();
    Document xmlDocument = builder.parse(fis);

    XPath xPath = XPathFactory.newInstance().newXPath();

    String Id = xPath.compile(IdExpr).evaluate(
            xmlDocument);




    return Id;
}