More efficient way to parse an XML doc in Java using XPath

package com.xxxxx.myapi;
 
import javax.servlet.http.HttpSession;
 
import javax.xml.xpath.*;
import java.net.*;
import java.io.*;
import org.xml.sax.*;
 
/* SAMPLE XML:
        <myapi>
                <ERROR_CODE>0</ERROR_CODE>
                <ERROR_MESSAGE>SUCCESS</ERROR_MESSAGE>
                <PAN_LENGTH>16</PAN_LENGTH>
                <ISSUE_NR_LENGTH>0</ISSUE_NR_LENGTH>
                <START_DATE>N</START_DATE>
                <SCHEME_LETTER>V</SCHEME_LETTER>
                <SCHEME_NAME>Visa</SCHEME_NAME>
                <PROCESSING_REQUIREMENT>0</PROCESSING_REQUIREMENT>
                <CRM_PAYMENT_TYPE>VISA</CRM_PAYMENT_TYPE>
                <CREDIT_OR_DEBIT>CREDIT</CREDIT_OR_DEBIT>
                <CONTINUITY>CONTINUOUS</CONTINUITY>
        </myapi>
*/
 
public class myapi extends CallOutAction {
 
        protected String xmpCallOutExecute(HttpSession session, Object[] args)
        throws Exception {       
 
                String sXMLResponse = "";
 
        /* -----------------------------------------------------------------
           CODE HERE TO CALL HTTP API THAT RETURNS AN XML DOC IN A String OBJECT
           SIMILAR TO THAT SHOWN IN THE EXAMPLE ABOVE, THIS IS STORED IN
           sXMLResponse
           ----------------------------------------------------------------- */
 
                // DECODE RESPONSE
                try {
                        
                        // CREATE NEW INSTANCES OF XPATH FACTORY OBJECT
                        XPathFactory factory = XPathFactory.newInstance();
                        XPath XPathObject = factory.newXPath();                 
 
                        // COLLECT DATA FROM XML RESPONSE
                        setResult(session, outResultCode, getXMLValue(sXMLResponse, XPathObject, "/myapi/ERROR_CODE")); 
                        setResult(session, outErrorMessage, getXMLValue(sXMLResponse, XPathObject, "/myapi/ERROR_MESSAGE")); 
                        setResult(session, outCardLength, getXMLValue(sXMLResponse, XPathObject, "/myapi/PAN_LENGTH")); 
                        setResult(session, outIssueNumberLength, getXMLValue(sXMLResponse, XPathObject, "/myapi/ISSUE_NR_LENGTH")); 
                        setResult(session, outRequireStartDate, getXMLValue(sXMLResponse, XPathObject, "/myapi/START_DATE")); 
                        setResult(session, outSchemeLetter, getXMLValue(sXMLResponse, XPathObject, "/myapi/SCHEME_LETTER")); 
                        setResult(session, outSchemeName, getXMLValue(sXMLResponse, XPathObject, "/myapi/SCHEME_NAME")); 
                        setResult(session, outCreditDebit, getXMLValue(sXMLResponse, XPathObject, "/myapi/CREDIT_OR_DEBIT")); 
                        setResult(session, outContinuity, getXMLValue(sXMLResponse, XPathObject, "/myapi/CONTINUITY")); 
 
                                                                        
                } catch (Exception e) {
                log.error("MYAPI IDENTIFY FAILED [PARSE XML RESPONSE ERROR]: " + e.getMessage(), session);
                        return fwdFail;             
                }
                
                return fwdSuccess;                  
        }
        
        private String getXMLValue(String sXMLResponse, XPath XPathObject, String sXPath)
        throws XPathExpressionException {
                
                // CREATE INPUT SOURCE
                StringReader sr = new StringReader(sXMLResponse);
                InputSource isXML = new InputSource(sr);
                
                // CREATE XPATH EXPRESSION
                XPathExpression xpeExpr = XPathObject.compile(sXPath);
                
                // RETURN RESULT
                return xpeExpr.evaluate(isXML);
                        
        }
}

                                  

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