Binding Objects
A Context
stores
its subordinates as a set of Binding
objects. A
binding is an association between an object and its name. Thus, as
we’ve already seen, a Binding
object contains an object, its name, and its class. We can add a new
Binding
to a Context
with the
bind( )
method. For example,
here’s how to add a binding for a new file object to
an existing Context
:
java.io.File newfile = java.io.File("c:\temp\newfile"); tempContext.bind("newfile", newfile);
Now, if we call list( )
on this
Context
, you see a new child named
newfile
. Recall in the previous section we said
that you have to drop out of JNDI to create a new file when using the
Sun filesystem provider. The previous example shows what we meant. To
create a file, use the java.io.File
constructor,
which isn’t part of JNDI. To bind the file into the
naming system, use the bind( )
method of
Context
.
If you try to bind a name to an object,
and the name has already been used, the method throws a
NameAlreadyBoundException
. If you want to bind a
new object to an existing name, use the rebind( )
method instead.
Context
also has an unbind( )
method you can use to remove a binding.
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