02. JNDI - start of work with Context interface (1)

[@ruixue6955]

3:30 code demo
4:06 (naming) *service provider* configuration
5:28 in this example case,
5:38 specify: use file system as service provider

[@takuntorfred2212]

Thank you Sir. Good simple practical explanation. Even a novice like me can understand. Thank you.

[@thecritique5464]

Best explanation of the concept. +1

[@galmalachi4859]

thank you very much! very helpful and well explained!

[@ashishburnwal9010]

Thank you for clear explanation, I have one question, let say I have a web-app called myApp, and it contains a context.xml. And during deployment the name of the context.xml is automatically changed to myApp.xml. Then how does the context lookup happens, given we are doing it with
Context envContext = (Context)initContext.lookup("java:comp/env");
How java:comp/env does all the magic?

[@PriyankaShinde-mp6lt]

I have created a topic in jms module in weblogic but while searching with it's jndi name I'm not able to lookup the topic. How to lookup that topic? Thank you..

[@svalyavasvalyava9867]

Thank you!!!

[@WojtekHejna]

Well done!

[@takuntorfred2212]

Sir I am using your tutorial to learn jndi. I have set up my code exactly as your own. But when I run it gives a null pointer exception. I am pasting the code below for your review. Please help; Thanks.
import javax.naming.Context;
import javax.naming.InitialContext;
import javax.naming.NamingException;
import java.util.*;
public class Ctxclass{
public static void main(String[] args) throws NamingException {
Hashtable env= new Hashtable();
env.put(Context.INITIAL_CONTEXT_FACTORY,"com.sun.jndi.fscontext.RefFSContextFactory");
env.put(Context.PROVIDER_URL,"file:/C:/");
Context ctx = new InitialContext(env);

Driver xyz = new Driver("princeton", "rav4");
ctx.bind("best driver", xyz);}}

import javax.naming.NamingException;
import javax.naming.Reference;
import javax.naming.Referenceable;
import javax.naming.StringRefAddr;
　
　
　
　
　
public class Driver implements Referenceable {
String name;
String model;
　
　
Driver(String name, String model) throws NamingException{
this.name = name; this.model = this.model;}
　
　
@Override
public Reference getReference() throws NamingException {

Reference bill = new Reference(Driver.class.getName());
bill.add(new StringRefAddr(name, this.name));
bill.add(new StringRefAddr(model, this.model));
return bill;}}
Exception in thread "main" java.lang.NullPointerException
at java.util.Hashtable.put(Unknown Source)
at com.sun.jndi.fscontext.RefFSContext.addObjectToBindings(RefFSContext.java:517)
at com.sun.jndi.fscontext.RefFSContext.bindObject(RefFSContext.java:337)
at com.sun.jndi.fscontext.RefFSContext.bind(RefFSContext.java:169)
at com.sun.jndi.fscontext.FSContext.bind(FSContext.java:167)
at javax.naming.InitialContext.bind(Unknown Source)
at Ctxclass.main(Ctxclass.java:22)

[@jedu1352]

Takuntor Fred I'd try working with D:\ partition. Windows can be very tricky and restrictive about creating files at root of C partition.

[@takuntorfred2212]

jEdu Thank you so very much sir. Thank you for responding. I tried your suggestion and it worked perfectly.Thanks. I'm really grateful.

[@aaroldaaroldson708]

4:08 We may access the Naming Service with anus service provider??? What are you saying??? Fix your audio or add subs PLEASE!

[@rallokkcaz]

Oof if you're here now.