Question

I need to parse through an XML document in the database and search for a given expression in it. Then, I must return a String value if the given expression is present in the XML else I need to parse through the next expression and return another String value and so on.

I achieved this by using the following code:

// An xml document is passed as a Node when getEntryType() method is called

 public static class XMLTextFields {
        public static String getEntryType(Node target) throws XPathExpressionException {
          XPathFactory factory = XPathFactory.newInstance();
          XPath xpath = factory.newXpath();
          String entryType = null;
          String [] expression = new String [] {"./libx:package", "./libx:libapp", "./libx:module"};

          String [] type = new String [] {"Package", "Libapp", "Module" };
          for (int i = 0; i < 3; i ++) {
              XPathExpression expr = xpath.compile(expression[i]);
              Object result = expr.evaluate(target, XPathConstants.NODESET);
              NodeList nodes = (NodeList) result;
              if (nodes.getLength() == 0)
                  continue;
              entryType = (type[i]);
          }
          return entryType;
        }
    }

I am wondering if there is a simpler way to do this? Meaning, is there a way to use the “expression” like a function which returns a string if the expression is present in the xml.

I am guessing I should be able to do something like this but am not exactly sure:

String [] Expression = new String [] {"[./libx:package]\"Package\"", ....} 

Meaning, return “Package” if libx:package node exists in the given XML

Answer 1

@ALL: Thanks!

I used:

XPathExpression expr = xpath.compile(“concat(substring(‘Package’,0,100*boolean(//libx:package)),” + “substring(‘Libapp’,0,100*boolean(//libx:libapp)),substring(‘Module’,0,100*boolean(//libx:module)))”);
expr.evaluate(target, XPathConstants.STRING);