On Mon, Dec 08, 2003 at 09:43:39PM -0800, David Jencks wrote:
> I'm sorry, I don't understand all about jndi.
> 
> Could you give an example of what this is for, and how it differs from  
> binding into the read only context refs whose targets are in say the  
> jmx context?

The ReadOnlyContext is used by the OpenEJB nova containers, so there is no jmx 
anything going on.  The situation is that I need to add another Context 
implementation, one built by OpenEJB, into the ReadOnlyContext of an 
EJBContainer.

Doing this by instantiating the ReadOnlyContext with a Map, where one of the 
values is the non-ReadOnlyContext context object.  Lookups to the respective 
name need to be delegated to that context object.

> Does this have the effect of making the ReadOnlyContext mutable, in  
> that you can look up whatever happens to be currently bound in the  
> subcontext?

It could if the Context added allowed bind operations, but in this case it 
doesn't.  The neat thing is that the "outside" context is only checked if the 
lookup failed against the ReadOnlyContext, so everything in the ReadOnlyContext 
essentially trumps the outside context.  This is useful for the UserTransaction 
object.

-David Blevins

> 
> Thanks
> david jencks
> 
> On Monday, December 8, 2003, at 09:03 PM, [EMAIL PROTECTED] wrote:
> 
> >dblevins    2003/12/08 21:03:49
> >
> >  Modified:    modules/core/src/java/org/apache/geronimo/naming/java
> >                        ReadOnlyContext.java
> >  Log:
> >  Added support to do lookups from other Context implementations.  In  
> >other words,
> >  sub-contexts under the context which aren't ReadOnlyContext  
> >implementations.
> >
> >  Revision  Changes    Path
> >  1.7       +23 -3      
> >incubator-geronimo/modules/core/src/java/org/apache/geronimo/naming/ 
> >java/ReadOnlyContext.java
> >
> >  Index: ReadOnlyContext.java
> >  ===================================================================
> >  RCS file:  
> >/home/cvs/incubator-geronimo/modules/core/src/java/org/apache/ 
> >geronimo/naming/java/ReadOnlyContext.java,v
> >  retrieving revision 1.6
> >  retrieving revision 1.7
> >  diff -u -r1.6 -r1.7
> >  --- ReadOnlyContext.java   16 Nov 2003 05:24:38 -0000      1.6
> >  +++ ReadOnlyContext.java   9 Dec 2003 05:03:49 -0000       1.7
> >  @@ -87,7 +87,7 @@
> >    * resolution phase performed by the JVM takes considerably longer,  
> >so for
> >    * optimum performance lookups should be coded like:</p>
> >    * <code>
> >  - *   Context componentContext = new  
> >InitialContext().lookup("java:comp");
> >  + *   Context componentContext = (Context)new  
> >InitialContext().lookup("java:comp");
> >    *   String envEntry = (String)  
> >componentContext.lookup("env/myEntry");
> >    *   String envEntry2 = (String)  
> >componentContext.lookup("env/myEntry2");
> >    * </code>
> >  @@ -122,7 +122,11 @@
> >       }
> >
> >       ReadOnlyContext(Hashtable env) {
> >  +        if (env == null) {
> >  +            this.env = new Hashtable();
> >  +        } else {
> >           this.env = new Hashtable(env);
> >  +        }
> >           this.bindings = Collections.EMPTY_MAP;
> >           this.treeBindings = Collections.EMPTY_MAP;
> >       }
> >  @@ -159,8 +163,24 @@
> >                       throw new NamingException("scheme " + scheme +  
> >" not recognized");
> >                   }
> >                   return ctx.lookup(name);
> >  +            } else {
> >  +                // Split out the first name of the path
> >  +                // and look for it in the bindings map.
> >  +                CompositeName path = new CompositeName(name);
> >  +
> >  +                if (path.size() == 0) {
> >  +                    return this;
> >  +                } else {
> >  +                    Object obj = bindings.get(path.get(0));
> >  +                    if (obj == null){
> >  +                        throw new NameNotFoundException(name);
> >  +                    } else if (obj instanceof Context &&  
> >path.size() > 1){
> >  +                        Context subContext = (Context) obj;
> >  +                        obj = subContext.lookup(path.getSuffix(1));
> >  +                    }
> >  +                    return obj;
> >  +                }
> >               }
> >  -            throw new NameNotFoundException(name);
> >           }
> >           if (result instanceof LinkRef) {
> >               LinkRef ref = (LinkRef) result;
> >
> >
> >
> >

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