I'm trying to use XPath to parse an XML string but I am getting only null values back. Does anyone have an idea where I might be going wrong in the code shown below?
public static void main(String[] args) {
String content = "<imagesXML><Images><Image><ImageUID Scope='Public' Type='Guid' Value='{7f2535d0-9a41-4997-9694-0a4de569e6d9}'/><CorbisID Scope='Public' Type='String' Value='42-15534232'/><Title Scope='Public' Type='String' Value='Animal'/><CreditLine Scope='Public' Type='String' Value='© Robert Llewellyn/Corbis'/><IsRoyaltyFree Scope='Public' Type='Boolean' Value='False'/><AspectRatio Scope='Public' Type='String' Value='1.500000'/><URL128 Scope='Public' Type='String' Value='http://cachens.corbis.com/CorbisImage/thumb/15/53/42/15534232/42-15534232.jpg'/></Image></Images></imagesXML>";
InputSource source = new InputSource(new StringReader(content));
XPath xPath = XPathFactory.newInstance().newXPath();
NodeList list = null;
try {
list = (NodeList) xPath.evaluate("//URL128[@Value]", source,
XPathConstants.NODESET);
} catch (Exception ex) {
System.out.println(ex.getMessage());
}
for (int i = 0; i < list.getLength(); i++) {
System.out.println(list.item(i));
}
}
The output from System.out is 'value=[URL128: null]', but it should be the URL I am trying to extract: http://cachens.corbis.com/CorbisImage/thumb/15/53/42/15534232/42-15534232.jpg
.
Any help appreciated, thanks.
What if you try changing your XPath evaluation statement from this:
list = (NodeList)xPath.evaluate("//URL128[@Value]",
source, XPathConstants.NODESET);
to this:
list = (NodeList) xPath.evaluate("//URL128/@Value",
source, XPathConstants.NODESET);
Note:
//URL128[@Value]
returns a list of all URL123
elements having a Value
attribute//URL128/@Value
returns a list of the Value
attributes from each URL128
element in the sourceNeither of these lists contain strings; they contain DOM types. You've got only one URL128
element in your source, yet you're asking for a NodeList
. You could simplify by using the following:
String url = xPath.evaluate("//URL128/@Value", source);
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