gov.nist.javax.sip.parser.ims.PPreferredServiceParser Maven / Gradle / Ivy
package gov.nist.javax.sip.parser.ims;
/*
* Conditions Of Use
*
* This software was developed by employees of the National Institute of
* Standards and Technology (NIST), an agency of the Federal Government.
* Pursuant to title 15 Untied States Code Section 105, works of NIST
* employees are not subject to copyright protection in the United States
* and are considered to be in the public domain. As a result, a formal
* license is not needed to use the software.
*
* This software is provided by NIST as a service and is expressly
* provided "AS IS." NIST MAKES NO WARRANTY OF ANY KIND, EXPRESS, IMPLIED
* OR STATUTORY, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTY OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, NON-INFRINGEMENT
* AND DATA ACCURACY. NIST does not warrant or make any representations
* regarding the use of the software or the results thereof, including but
* not limited to the correctness, accuracy, reliability or usefulness of
* the software.
*
* Permission to use this software is contingent upon your acceptance
* of the terms of this agreement
*
* .
*
*/
import java.text.ParseException;
import javax.sip.InvalidArgumentException;
import gov.nist.javax.sip.header.SIPHeader;
import gov.nist.javax.sip.header.ims.PPreferredService;
import gov.nist.javax.sip.header.ims.ParameterNamesIms;
import gov.nist.javax.sip.parser.HeaderParser;
import gov.nist.javax.sip.parser.Lexer;
import gov.nist.javax.sip.parser.TokenTypes;
/**
*
* @author aayush.bhatnagar
* Rancore Technologies Pvt Ltd, Mumbai India.
*
* Parse this:
* P-Preferred-Service: urn:urn-7:3gpp-service.exampletelephony.version1
*
*/
public class PPreferredServiceParser extends HeaderParser implements TokenTypes{
protected PPreferredServiceParser(Lexer lexer) {
super(lexer);
}
public PPreferredServiceParser(String pps)
{
super(pps);
}
/**
* "The URN consists of a hierarchical service identifier or application
* identifier, with a sequence of labels separated by periods.The left-most label is
* the most significant one and is called 'top-level service
* identifier', while names to the right are called 'sub-services' or
* 'sub-applications'.
*
* For any given service identifier, labels can be removed right-to-left and
* the resulting URN is still valid, referring a more generic
* service, with the exception of the top-level service identifier
* and possibly the first sub-service or sub-application identifier.
*
* Labels cannot be removed beyond a defined basic service, for
* example, the label w.x may define a service, but the label w may
* only define an assignment authority for assigning subsequent
* values and not define a service in its own right. In other words,
* if a service identifier 'w.x.y.z' exists, the URNs 'w.x' and
* 'w.x.y' are also valid service identifiers, but w may not be a
* valid service identifier if it merely defines who is responsible"
*
* TODO: PLEASE VALIDATE MY UNDERSTANDING OF THE ABOVE TEXT :)
* @ranga: Please validate my understanding of the above text in the draft :)
* This last para is a little ambiguous.I will only check that atleast
* 1 sub-service or 1 sub-application is present in the URN declaration.
* If not, I throw an exception. I thought of not throwing an exception
* and returning whatever was encoded..but the resultant encoding wont
* make sense. It would be something like-->
* urn:urn-7:3gpp-service OR urn:urn-7:3gpp-application alone with no sub-services
* or sub-applications. This is bound to cause an error at the recepient later.
*
* Sub-service and Application identifiers are not maintained by IANA and
* are organization/application dependent (Section 8.2). So we cannot gurantee what lies
* beyond the first sub-service or sub-application identifier. It should be the responsibility
* of the application to make sense of the entire URN holistically. We can only check for the
* standardized part as per the ABNF.
*/
public SIPHeader parse() throws ParseException {
if(debug)
dbg_enter("PPreferredServiceParser.parse");
try
{
this.lexer.match(TokenTypes.P_PREFERRED_SERVICE);
this.lexer.SPorHT();
this.lexer.match(':');
this.lexer.SPorHT();
PPreferredService pps = new PPreferredService();
String urn = this.lexer.getBuffer();
if(urn.contains(ParameterNamesIms.SERVICE_ID)){
if(urn.contains(ParameterNamesIms.SERVICE_ID_LABEL))
{
String serviceID = urn.split(ParameterNamesIms.SERVICE_ID_LABEL+".")[1];
if(serviceID.trim().equals(""))
try {
throw new InvalidArgumentException("URN should atleast have one sub-service");
} catch (InvalidArgumentException e) {
e.printStackTrace();
}
else
pps.setSubserviceIdentifiers(serviceID);
}
else if(urn.contains(ParameterNamesIms.APPLICATION_ID_LABEL))
{
String appID = urn.split(ParameterNamesIms.APPLICATION_ID_LABEL)[1];
if(appID.trim().equals(""))
try {
throw new InvalidArgumentException("URN should atleast have one sub-application");
} catch (InvalidArgumentException e) {
e.printStackTrace();
}
else
pps.setApplicationIdentifiers(appID);
}
else
{
try {
throw new InvalidArgumentException("URN is not well formed");
} catch (InvalidArgumentException e) {
e.printStackTrace();
}
}
}
super.parse();
return pps;
}
finally{
if(debug)
dbg_enter("PPreferredServiceParser.parse");
}
}
}