Generate/get xpath from XML node java
I'm interested in advice/pseudocode code/explanation rather than actual implementation.
- I'd like to go trough xml document, all of its nodes
- Check the node for attribute existence
Case if node doesn't have attribute, get/generate String with value of its xpath
Case if node does have attributes, iterate trough attribute list and create xpath for each attribute including the node as well.
Word of advice? Hopefully you will provide some useful intel
EDIT:
Reason for doing this is .. I'm writing automated tests in jmeter, so for every request I need to verify that request actually did its job so I'm asserting results by getting nodes values with xpath.(extra info - irrelevant)
When the request is small its not problem to create asserts by hand, but for larger ones its a really pain in the .. (extra info - irrelevant)
BOUNTY :
I'm looking for java approach
Goal
My goal is to achieve following from this ex xml file :
<root>
<elemA>one</elemA>
<elemA attribute1='first' attribute2='second'>two</elemA>
<elemB>three</elemB>
<elemA>four</elemA>
<elemC>
<elemB>five</elemB>
</elemC>
</root>
to produce the following :
//root[1]/elemA[1]='one'
//root[1]/elemA[2]='two'
//root[1]/elemA[2][@attribute1='first']
//root[1]/elemA[2][@attribute2='second']
//root[1]/elemB[1]='three'
//root[1]/elemA[3]='four'
//root[1]/elemC[1]/elemB[1]='five'
Explained :
- If node value/text is not null/zero, get xpath , add = 'nodevalue' for assertion purpose
- If node has attributes create assert for them too
BOUNTY UPDATE :
I found this example, it doesn't produce the correct results , but I'm looking something like this:
http://www.coderanch.com/how-to/java/SAXCreateXPath
Update:
@c0mrade has updated his question. Here is a solution to it:
This XSLT transformation:
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:output method="text"/>
<xsl:strip-space elements="*"/>
<xsl:variable name="vApos">'</xsl:variable>
<xsl:template match="*[@* or not(*)] ">
<xsl:if test="not(*)">
<xsl:apply-templates select="ancestor-or-self::*" mode="path"/>
<xsl:value-of select="concat('=',$vApos,.,$vApos)"/>
<xsl:text>
</xsl:text>
</xsl:if>
<xsl:apply-templates select="@*|*"/>
</xsl:template>
<xsl:template match="*" mode="path">
<xsl:value-of select="concat('/',name())"/>
<xsl:variable name="vnumPrecSiblings" select=
"count(preceding-sibling::*[name()=name(current())])"/>
<xsl:if test="$vnumPrecSiblings">
<xsl:value-of select="concat('[', $vnumPrecSiblings +1, ']')"/>
</xsl:if>
</xsl:template>
<xsl:template match="@*">
<xsl:apply-templates select="../ancestor-or-self::*" mode="path"/>
<xsl:value-of select="concat('[@',name(), '=',$vApos,.,$vApos,']')"/>
<xsl:text>
</xsl:text>
</xsl:template>
</xsl:stylesheet>
when applied on the provided XML document:
<root>
<elemA>one</elemA>
<elemA attribute1='first' attribute2='second'>two</elemA>
<elemB>three</elemB>
<elemA>four</elemA>
<elemC>
<elemB>five</elemB>
</elemC>
</root>
produces exactly the wanted, correct result:
/root/elemA='one'
/root/elemA[2]='two'
/root/elemA[2][@attribute1='first']
/root/elemA[2][@attribute2='second']
/root/elemB='three'
/root/elemA[3]='four'
/root/elemC/elemB='five'
When applied to the newly-provided document by @c0mrade:
<root>
<elemX serial="kefw90234kf2esda9231">
<id>89734</id>
</elemX>
</root>
again the correct result is produced:
/root/elemX='89734'
/root/elemX[@serial='kefw90234kf2esda9231']
Explanation:
Only elements that have no children elements, or have attributes are matched and processed.
For any such element, if it doesn't have children-elements all of its ancestor-or self elements are processed in a specific mode, named
'path'. Then the"='theValue'"part is output and then a NL character.All attributes of the matched element are then processed.
Then finally, templates are applied to all children-elements.
Processing an element in the
'path'mode is simple: A/character and the name of the element are output. Then, if there are preceding siblings with the same name, a "[numPrecSiblings+1]` part is output.Processing of attributes is simple: First all
ancestor-or-self::elements of its parent are processed in'path'mode, then the [attrName=attrValue] part is output, followed by a NL character.
Do note:
Names that are in a namespace are displayed without any problem and in their initial readable form.
To aid readability, an index of
[1]is never displayed.
Below is my initial answer (may be ignored)
Here is a pure XSLT 1.0 solution:
Below is a sample xml document and a stylesheet that takes a node-set parameter and produces one valid XPath expression for every member-node.
stylesheet (buildPath.xsl):
<xsl:stylesheet version='1.0'
xmlns:xsl='http://www.w3.org/1999/XSL/Transform'
xmlns:msxsl="urn:schemas-microsoft-com:xslt"
>
<xsl:output method="text"/>
<xsl:variable name="theParmNodes" select="//namespace::*[local-name() =
'myNamespace']"/>
<xsl:template match="/">
<xsl:variable name="theResult">
<xsl:for-each select="$theParmNodes">
<xsl:variable name="theNode" select="."/>
<xsl:for-each select="$theNode |
$theNode/ancestor-or-self::node()[..]">
<xsl:element name="slash">/</xsl:element>
<xsl:choose>
<xsl:when test="self::*">
<xsl:element name="nodeName">
<xsl:value-of select="name()"/>
<xsl:variable name="thisPosition"
select="count(preceding-sibling::*[name(current()) =
name()])"/>
<xsl:variable name="numFollowing"
select="count(following-sibling::*[name(current()) =
name()])"/>
<xsl:if test="$thisPosition + $numFollowing > 0">
<xsl:value-of select="concat('[', $thisPosition +
1, ']')"/>
</xsl:if>
</xsl:element>
</xsl:when>
<xsl:otherwise> <!-- This node is not an element -->
<xsl:choose>
<xsl:when test="count(. | ../@*) = count(../@*)">
<!-- Attribute -->
<xsl:element name="nodeName">
<xsl:value-of select="concat('@',name())"/>
</xsl:element>
</xsl:when>
<xsl:when test="self::text()"> <!-- Text -->
<xsl:element name="nodeName">
<xsl:value-of select="'text()'"/>
<xsl:variable name="thisPosition"
select="count(preceding-sibling::text())"/>
<xsl:variable name="numFollowing"
select="count(following-sibling::text())"/>
<xsl:if test="$thisPosition + $numFollowing > 0">
<xsl:value-of select="concat('[', $thisPosition +
1, ']')"/>
</xsl:if>
</xsl:element>
</xsl:when>
<xsl:when test="self::processing-instruction()">
<!-- Processing Instruction -->
<xsl:element name="nodeName">
<xsl:value-of select="'processing-instruction()'"/>
<xsl:variable name="thisPosition"
select="count(preceding-sibling::processing-instruction())"/>
<xsl:variable name="numFollowing"
select="count(following-sibling::processing-instruction())"/>
<xsl:if test="$thisPosition + $numFollowing > 0">
<xsl:value-of select="concat('[', $thisPosition +
1, ']')"/>
</xsl:if>
</xsl:element>
</xsl:when>
<xsl:when test="self::comment()"> <!-- Comment -->
<xsl:element name="nodeName">
<xsl:value-of select="'comment()'"/>
<xsl:variable name="thisPosition"
select="count(preceding-sibling::comment())"/>
<xsl:variable name="numFollowing"
select="count(following-sibling::comment())"/>
<xsl:if test="$thisPosition + $numFollowing > 0">
<xsl:value-of select="concat('[', $thisPosition +
1, ']')"/>
</xsl:if>
</xsl:element>
</xsl:when>
<!-- Namespace: -->
<xsl:when test="count(. | ../namespace::*) =
count(../namespace::*)">
<xsl:variable name="apos">'</xsl:variable>
<xsl:element name="nodeName">
<xsl:value-of select="concat('namespace::*',
'[local-name() = ', $apos, local-name(), $apos, ']')"/>
</xsl:element>
</xsl:when>
</xsl:choose>
</xsl:otherwise>
</xsl:choose>
</xsl:for-each>
<xsl:text>
</xsl:text>
</xsl:for-each>
</xsl:variable>
<xsl:value-of select="msxsl:node-set($theResult)"/>
</xsl:template>
</xsl:stylesheet>
xml source (buildPath.xml):
<!-- top level Comment -->
<root>
<nodeA>textA</nodeA>
<nodeA id="nodeA-2">
<?myProc ?>
xxxxxxxx
<nodeB/>
<nodeB xmlns:myNamespace="myTestNamespace">
<!-- Comment within /root/nodeA[2]/nodeB[2] -->
<nodeC/>
<!-- 2nd Comment within /root/nodeA[2]/nodeB[2] -->
</nodeB>
yyyyyyy
<nodeB/>
<?myProc2 ?>
</nodeA>
</root>
<!-- top level Comment -->
Result:
/root/nodeA[2]/nodeB[2]/namespace::*[local-name() = 'myNamespace']
/root/nodeA[2]/nodeB[2]/nodeC/namespace::*[local-name() =
'myNamespace']
Here is how this can be done with SAX:
import java.util.HashMap;
import java.util.Map;
import org.xml.sax.Attributes;
import org.xml.sax.SAXException;
import org.xml.sax.XMLReader;
import org.xml.sax.helpers.DefaultHandler;
public class FragmentContentHandler extends DefaultHandler {
private String xPath = "/";
private XMLReader xmlReader;
private FragmentContentHandler parent;
private StringBuilder characters = new StringBuilder();
private Map<String, Integer> elementNameCount = new HashMap<String, Integer>();
public FragmentContentHandler(XMLReader xmlReader) {
this.xmlReader = xmlReader;
}
private FragmentContentHandler(String xPath, XMLReader xmlReader, FragmentContentHandler parent) {
this(xmlReader);
this.xPath = xPath;
this.parent = parent;
}
@Override
public void startElement(String uri, String localName, String qName, Attributes atts) throws SAXException {
Integer count = elementNameCount.get(qName);
if(null == count) {
count = 1;
} else {
count++;
}
elementNameCount.put(qName, count);
String childXPath = xPath + "/" + qName + "[" + count + "]";
int attsLength = atts.getLength();
for(int x=0; x<attsLength; x++) {
System.out.println(childXPath + "[@" + atts.getQName(x) + "='" + atts.getValue(x) + ']');
}
FragmentContentHandler child = new FragmentContentHandler(childXPath, xmlReader, this);
xmlReader.setContentHandler(child);
}
@Override
public void endElement(String uri, String localName, String qName) throws SAXException {
String value = characters.toString().trim();
if(value.length() > 0) {
System.out.println(xPath + "='" + characters.toString() + "'");
}
xmlReader.setContentHandler(parent);
}
@Override
public void characters(char[] ch, int start, int length) throws SAXException {
characters.append(ch, start, length);
}
}
It can be tested with:
import java.io.FileInputStream;
import javax.xml.parsers.SAXParser;
import javax.xml.parsers.SAXParserFactory;
import org.xml.sax.InputSource;
import org.xml.sax.XMLReader;
public class Demo {
public static void main(String[] args) throws Exception {
SAXParserFactory spf = SAXParserFactory.newInstance();
SAXParser sp = spf.newSAXParser();
XMLReader xr = sp.getXMLReader();
xr.setContentHandler(new FragmentContentHandler(xr));
xr.parse(new InputSource(new FileInputStream("input.xml")));
}
}
This will produce the desired output:
//root[1]/elemA[1]='one'
//root[1]/elemA[2][@attribute1='first]
//root[1]/elemA[2][@attribute2='second]
//root[1]/elemA[2]='two'
//root[1]/elemB[1]='three'
//root[1]/elemA[3]='four'
//root[1]/elemC[1]/elemB[1]='five'