ONSHelper.java

package kr.ac.kaist.resl.lilliput.util;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.Hashtable;
import java.util.Map;

import javax.naming.NamingEnumeration;
import javax.naming.NamingException;
import javax.naming.directory.Attributes;
import javax.naming.directory.DirContext;
import javax.naming.directory.InitialDirContext;

import org.epcglobalinc.tdt.LevelTypeList;
import org.fosstrak.tdt.TDTEngine;
import org.json.JSONException;
import org.json.JSONObject;

public class ONSHelper {
	@SuppressWarnings("unchecked")
	public static JSONObject getNAPTRFromONS(String url, String hostName)
	{
			//Phase 2 : DNS Resolving via ONS
			//We use JNDI for using DNS
			try
			{
				Hashtable<String, String> env = new Hashtable<String,String>();
				// JNDI Properties
				env.put("java.naming.factory.initial", "com.sun.jndi.dns.DnsContextFactory");
				// IPv6 address of ONS
				env.put("java.naming.provider.url", url);
				// Variable Initialize
				Attributes returnAttributes = null;
				@SuppressWarnings("rawtypes")
				NamingEnumeration attributeEnum = null;
				@SuppressWarnings("rawtypes")
				ArrayList results = new ArrayList();
				
				DirContext ictx = new InitialDirContext(env);
				//ONS use NAPTR Type
				
				returnAttributes = ictx.getAttributes(hostName, new String[]{"NAPTR"});
				
				if(returnAttributes.size() > 0) {
					attributeEnum = returnAttributes.get("NAPTR").getAll();
					while(attributeEnum.hasMore()) results.add((String)attributeEnum.next());
				}
				//{naptr=NAPTR: 0 0 u EPC+ws !^.*$!http://143.248.106.26:8880/EcoMiddleware/services/SmartMetering! ., 
				//0 0 u EPC+epcis !^.*$!http://[2002:8ff8:6a89::8ff8:6a89]/epcis-repository-0.4.2/query! .}
				String result;
				String[] subResults = null;
				JSONObject returnJson = new JSONObject();
				//ONS can returns several records ( Service ) 
				for( int i = 0 ; i < results.size() ; i ++ )
				{					
					result = (String)results.get(i);
					System.out.println("Returned Service related to EPC : " + result);
					//Split by delimiter " "  <-- whitespace
					subResults = result.split(" ");
					if( subResults[3].equals("EPC+ws"))
					{
						String SEP = subResults[4].substring(6, subResults[4].length()-1);
						returnJson.put("ws", SEP);
					}
					else if( subResults[3].equals("EPC+epcis"))
					{
						String SEP = subResults[4].substring(6, subResults[4].length()-1);
						returnJson.put("epcis", SEP);
					}
					else if( subResults[3].equals("EPC+rest"))
					{
						String SEP = subResults[4].substring(6, subResults[4].length()-1);
						returnJson.put("rest", SEP);
					}
					
				}
				return returnJson;
			}
			catch( NamingException ne)
			{
				ne.printStackTrace();
				
			} catch (JSONException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
			return null;	
	}
	
	@SuppressWarnings("unchecked")
	public static JSONObject getNAPTRFromONSWithEPC(String url, String epc)
	{
			//"dns://[2002:8ff8:6a87::8ff8:6a87]"
			// Phase 1 : Using TDTEngine 
			// TDTEngine for translating any epc format to ONS hostname
			// Initialize
			TDTEngine engine = null;
			Map<String, String> params;
			params = new HashMap<String, String>();
			if( engine == null )
			{
				try
				{
					engine = new TDTEngine();
				}
				catch ( Exception e )
				{
					e.printStackTrace(System.err);
					
				}
			}		
			
			params.put("taglength", "96");
			//Run the TDT Engine
			// convert(  source epc, parameters, target type )
			String hostName = engine.convert(epc, params, LevelTypeList.ONS_HOSTNAME);
			//You get Host Name Of EPC
			System.out.println("host name of EPC : "+ hostName);

			//Phase 2 : DNS Resolving via ONS
			//We use JNDI for using DNS
			try
			{
				Hashtable<String, String> env = new Hashtable<String,String>();
				// JNDI Properties
				env.put("java.naming.factory.initial", "com.sun.jndi.dns.DnsContextFactory");
				// IPv6 address of ONS
				env.put("java.naming.provider.url", url);
				// Variable Initialize
				Attributes returnAttributes = null;
				@SuppressWarnings("rawtypes")
				NamingEnumeration attributeEnum = null;
				@SuppressWarnings("rawtypes")
				ArrayList results = new ArrayList();
				
				DirContext ictx = new InitialDirContext(env);
				//ONS use NAPTR Type
				
				returnAttributes = ictx.getAttributes(hostName, new String[]{"NAPTR"});
				
				if(returnAttributes.size() > 0) {
					attributeEnum = returnAttributes.get("NAPTR").getAll();
					while(attributeEnum.hasMore()) results.add((String)attributeEnum.next());
				}
				//{naptr=NAPTR: 0 0 u EPC+ws !^.*$!http://143.248.106.26:8880/EcoMiddleware/services/SmartMetering! ., 
				//0 0 u EPC+epcis !^.*$!http://[2002:8ff8:6a89::8ff8:6a89]/epcis-repository-0.4.2/query! .}
				String result;
				String[] subResults = null;
				JSONObject returnJson = new JSONObject();
				//ONS can returns several records ( Service ) 
				for( int i = 0 ; i < results.size() ; i ++ )
				{					
					result = (String)results.get(i);
					System.out.println("Returned Service related to EPC : " + result);
					//Split by delimiter " "  <-- whitespace
					subResults = result.split(" ");
					if( subResults[3].equals("EPC+ws"))
					{
						String SEP = subResults[4].substring(6, subResults[4].length()-1);
						returnJson.put("ws", SEP);
					}
					else if( subResults[3].equals("EPC+epcis"))
					{
						String SEP = subResults[4].substring(6, subResults[4].length()-1);
						returnJson.put("epcis", SEP);
					}
					else if( subResults[3].equals("EPC+rest"))
					{
						String SEP = subResults[4].substring(6, subResults[4].length()-1);
						returnJson.put("rest", SEP);
					}
				}
				return returnJson;
			}
			catch( NamingException ne)
			{
				ne.printStackTrace();
				
			} catch (JSONException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
			return null;	
	}
}