iterate a doc with sax and change xpath expression at run time

[Ludovik Lax]

Hi, I d' like to evaluate an xpath expresion for getting the attribute value:

 	<property name="userDistrib" value="0007.02"/>
   

Here , I use attribute:value and get search / replace :

  XPath xpath = XPathFactory.newInstance().newXPath();
        NodeList usersnodes = null;
        try {
            usersnodes = (NodeList) xpath.evaluate("//attribute::value", doc, XPathConstants.NODESET);
        } catch (XPathExpressionException e2) {
            LOG.error("XPath expression error");
        }

        // alter user node default value
        for (int i = 0; i < usersnodes.getLength(); i++) {
            System.out.println(usersnodes.item(i).getNodeValue());
            if (usersnodes.item(i).getNodeValue().equals("0007.02")) {
                usersnodes.item(i).setTextContent(this.userValue);
            }   

But, how to make the xpath expression to point directly for the value attribute: <property name="userDistrib" value="0007.02"/>

My goal is to modify this value in iterator, so a hardcoded value to replace is not possible ?

[Paul Clapham]

I've typed two possible answers in here and erased both of them, because I can't tell what you are asking. I think you're going to have to explain this:

My goal is to modify this value in iterator, so a hardcoded value to replace is not possible ?

in some different way. Perhaps you could explain what that code is meant to do and what it does instead and why that's wrong.

[Ludovik Lax]

That is getting a modification on xpath , each time an iteration is done:

   for (int i = 1; i < userDistrib.length; i++) {
                    GeneratorXpath gx = new GeneratorXpath(userDistrib[i - 1], userDistrib[i]);
                    try { 

so i have used this expression

   usersnodes.item(6).setTextContent(this.userNext); 

, but maybe a better way to set this independant of the order on attribute::value result

[William Brogden]

But XPath is going to use a DOM anyway, isn't it? Why are we talking SAX here?

What is GeneratorXpath?

Bill

[Paul Clapham]

Arthur Burma wrote:so i have used this expression

   usersnodes.item(6).setTextContent(this.userNext); 

, but maybe a better way to set this independant of the order on attribute::value result

Well, assuming we are actually talking about DOM programming here (your code certainly looks like that): you should be getting an Attr node from that XPath expression. So why wouldn't you just use its setValue() method, as per the documentation?

I'm saying that based on the fact that you haven't told us that you are having a problem, or what it is if there is a problem. So I'm just guessing at things to say. So perhaps you could do that. If there are exceptions, show us the stack trace. If some output differs from what you think it should be, show it to us and tell us what the difference is.

[Ludovik Lax]

To keep things simple I have to clarify , hereis the xml :

    <create-entities count="1" name="T_PERUSERUBNALERTS_PU_AIRCRAFT">
			<consumer class="org.databene.platform.csv.CSVEntityExporter" id="t_peruserubnalerts_pu">
				<property name="uri" value="loader/CSV/T_PERUSERUBNALERTS_PU.CSV"/>

Actually I just want to modify the value in property with replacing the string "loader/CSV" by "output/local" for instance... I have some trouble <ith xpath for that because it's not outside an attribute tag;

regards

[Paul Clapham]

Okay. So:

(1) Find the attribute.

(2) Extract its value into a String variable.

(3) Get the corrected value into a String variable.

(4) Set the new value of the attribute.

When you're done, don't forget to serialize your DOM. Changing the value in memory and not writing that out to a file can lead you to believe that the value wasn't changed.