How to read elements in a xml file sent as a string

Question

Hi,
I am new to BPEL and i am working on a requirement where i receive the XML message as a String from an AQ. And I am not able parse the xml to read the individual elements of it. Appreciate your help on this.
The (sample)input message from Q is which i am able to see in the BPEL console:
<BUGINFO_XML>
<XML_MESSAGE>
<?xml version="1.0"?>
<BUGINFO>
<SR_ID>3-29OU7OF</SR_ID>
<OBJECT_TYPE>UPDATE_PREBUG</OBJECT_TYPE>
<RESERVED_BUG_NUM>8221084</RESERVED_BUG_NUM>
<TYPE>Predefect Update</TYPE>
<AUDIENCE>INTERNAL</AUDIENCE>
<COMMENT>TEST activity by Sireesha</COMMENT>
</BUGINFO>
</XML_MESSAGE>
</BUGINFO_XML>
and the corresponding xsd file is:
<schema targetNamespace="http://xmlns.oracle.com/xdb/ORIONCC"
xmlns="http://www.w3.org/2001/XMLSchema"
xmlns:ORIONCC="http://xmlns.oracle.com/xdb/ORIONCC"
elementFormDefault="unqualified" attributeFormDefault="qualified">
<complexType name="BUGINFO_XML">
<sequence>
<element name="XML_MESSAGE" type="string" nillable="true" minOccurs="0"/>
</sequence>
</complexType>
<element name="BUGINFO_XML" type="ORIONCC:BUGINFO_XML" />
</schema>
i have created a variable(called VariableXML) of element type of the above xsd type({http://xmlns.oracle.com/xdb/ORIONCC}BUGINFO_XML) and using ora:parseEscapedXML method, i copied the input data to this variable and i can see the data copied fine to this variable, but after that i am not able to traverse to the individual element of it say i want the value of SR_ID which i am not able to get.
<VariableXML>
<BUGINFO_XML>
<SR_ID>3-29OU7OF</SR_ID>
<OBJECT_TYPE>UPDATE_PREBUG</OBJECT_TYPE>
<RESERVED_BUG_NUM>8221084</RESERVED_BUG_NUM>
<TYPE>Predefect Update</TYPE>
<AUDIENCE>INTERNAL</AUDIENCE>
<COMMENT>TEST activity by Sireesha</COMMENT>
</BUGINFO_XML>
</VariableXML>
When i see the structure of this variable in the Assign activity i can see only up to '/ns2:BUGINFO_XML/XML_MESSAGE' but not the individual elements.
Please let me know how can i parse this xml to read the elements of it.
I am using jdev 11.1.1.4 and weblogic 10.3
Thanks,
Sireesha
Edited by: user12217808 on Jul 27, 2012 7:10 AM

Answer 1

Thanks for replying Tarak,
I have taken the XML generated by VariableXML variable and generated a XSD out of it and that looks like below.
<?xml version="1.0" encoding="windows-1252" ?>
<xsd:schema xmlns:xsd="http://www.w3.org/2001/XMLSchema"
xmlns="http://www.example.org"
targetNamespace="http://www.example.org"
elementFormDefault="qualified">
<xsd:element name="BUGINFO_XML">
<xsd:complexType>
<xsd:sequence>
<xsd:element name="SR_ID" type="xsd:string"/>
<xsd:element name="OBJECT_TYPE" type="xsd:string"/>
<xsd:element name="RESERVED_BUG_NUM" type="xsd:integer"/>
<xsd:element name="TYPE" type="xsd:string"/>
<xsd:element name="AUDIENCE" type="xsd:string"/>
<xsd:element name="COMMENT" type="xsd:string"/>
</xsd:sequence>
</xsd:complexType>
</xsd:element>
</xsd:schema>
Then I have created a variable called VariableBugInfo of this element type ({http://www.example.org}BUGINFO_XML) and tried parsing it as below.
<assign name = 'Assign2'>
<copy>
<from expression="oraext:parseXML(bpws:getVariableData('VariableXML','/ns2:BUGINFO_XML'))"/>
<to variable="VariableBugInfo" query="/ns4:BUGINFO_XML"/>
</copy>
</assign>
then i got the below error in the bpel console when im testing my bpel process.
The following exception occurred while attempting to execute operation copy at line 118
<?xml-stylesheet href="chrome://global/locale/intl.css" type="text/css"?>
-<parsererror>
XML Parsing Error: junk after document element
Location: http://slce26vm164.us.oracle.com:7001/em/ai/sca/share/audit/nfdg/displayInstance.jsp?locatorobjkey=Farm_mosbpelmosbpelsoa_server1soa-infra&instanceid=bpel%3A70555
Line Number 7, Column 1:
<sourcetext>
<root class="javax.xml.xpath.XPathExpressionException">internal xpath error<stack><f>oracle.xml.xpath.JXPathExpression.evaluate#242</f><f>com.collaxa.cube.xml.xpath.BPELXPathUtil.evaluate#240</f><f>com.collaxa.cube.engine.ext.bpel.common.BPELWMPHelper.evalFromValue#339</f><f>com.collaxa.cube.engine.ext.bpel.v1.wmp.BPEL1AssignWMP.__executeStatements#137</f><f>com.collaxa.cube.engine.ext.bpel.common.wmp.BaseBPELActivityWMP.perform#158</f><f>com.collaxa.cube.engine.CubeEngine._performActivity#2463</f><f>com.collaxa.cube.engine.CubeEngine.performActivity#2334</f><f>com.collaxa.cube.engine.CubeEngine.handleWorkItem#1115</f><f>com.collaxa.cube.engine.dispatch.message.instance.PerformMessageHandler.handleLocal#73</f><f>com.collaxa.cube.engine.dispatch.DispatchHelper.handleLocalMessage#220</f><f>com.collaxa.cube.engine.dispatch.DispatchHelper.sendMemory#328</f><f>com.collaxa.cube.engine.CubeEngine.endRequest#4350</f><f>com.collaxa.cube.engine.CubeEngine.endRequest#4281</f><f>com.collaxa.cube.engine.CubeEngine.createAndInvoke#679</f><f>com.collaxa.cube.engine.delivery.DeliveryService.handleInvoke#654</f><f>com.collaxa.cube.engine.ejb.impl.CubeDeliveryBean.handleInvoke#293</f><f>...</f></stack></root>
^
</sourcetext>
</parsererror>
but when i tried a normal copy from VariableXML BUGINFO to VariableBugInfo as below, i am not getting any error but its not actually copying the contents to individual tags, because after this Assign i created a simple string variable(objTypeVar) and when i tried to copy TYPE element value to it, it says 'The result is empty for the XPath expression : "/ns4:BUGINFO_XML/ns4:TYPE".'
<assign name="Assign2">
<copy>
<from variable="VariableXML" query="/ns2:BUGINFO_XML"/>
<to variable="VariableBugInfo" query="/ns4:BUGINFO_XML"/>
</copy>
</assign>
<assign name="Assign3">
<copy>
<from variable="VariableBugInfo"
query="/ns4:BUGINFO_XML/ns4:TYPE"/>
<to variable="objTypeVar"/>
</copy>
</assign>
Result in console for VariableBugInfo for Assign2:
<VariableBugInfo>
<BUGINFO_XML>
<SR_ID>3-29OU7OF</SR_ID>
<OBJECT_TYPE>UPDATE_PREBUG</OBJECT_TYPE>
<RESERVED_BUG_NUM>8221084</RESERVED_BUG_NUM>
<TYPE>Predefect Update</TYPE>
<AUDIENCE>INTERNAL</AUDIENCE>
<COMMENT>TEST activity by Sireesha</COMMENT>
</BUGINFO_XML>
</VariableBugInfo>
For Assign 3:
Error in evaluate <from> expression at line "141". The result is empty for the XPath expression : "/ns4:BUGINFO_XML/ns4:TYPE".
I feel there is something i am missing in the XSD and the target namespace which is causing the issue. I am not sure what i should provide in the target namesapce in the new xsd which i created based on the value of VariableXML , so that it actually parses the xml and copies exact elements of it.
Please let me know if i am doing something wrong anywhere.
Thanks,
Sireesha