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<A NAME="getObjectInstance(java.lang.Object, javax.naming.Name, javax.naming.Context, java.util.Hashtable)"><!-- --></A><H3>
getObjectInstance</H3>
<PRE>
public <A HREF="../../../java/lang/Object.html">Object</A> <B>getObjectInstance</B>(<A HREF="../../../java/lang/Object.html">Object</A>&nbsp;obj,
                                <A HREF="../../../javax/naming/Name.html">Name</A>&nbsp;name,
                                <A HREF="../../../javax/naming/Context.html">Context</A>&nbsp;nameCtx,
                                <A HREF="../../../java/util/Hashtable.html">Hashtable</A>&nbsp;environment)
                         throws <A HREF="../../../java/lang/Exception.html">Exception</A></PRE>
<DL>
<DD>Creates an object using the location or reference information
 specified.  
 <p>
 Special requirements of this object are supplied
 using <code>environment</code>.
 An example of such an environment property is user identity
 information. 
<p>
 <tt>NamingManager.getObjectInstance()</tt>
 successively loads in object factories and invokes this method
 on them until one produces a non-null answer.  When an exception
 is thrown by an object factory, the exception is passed on to the caller
 of <tt>NamingManager.getObjectInstance()</tt>
 (and no search is made for other factories
 that may produce a non-null answer).
 An object factory should only throw an exception if it is sure that
 it is the only intended factory and that no other object factories
 should be tried.
 If this factory cannot create an object using the arguments supplied,
 it should return null. 
<p>
 A <em>URL context factory</em> is a special ObjectFactory that
 creates contexts for resolving URLs or objects whose locations
 are specified by URLs.  The <tt>getObjectInstance()</tt> method
 of a URL context factory will obey the following rules.
 <ol>
 <li>If <code>obj</code> is null, create a context for resolving URLs of the
 scheme associated with this factory. The resulting context is not tied
 to a specific URL:  it is able to handle arbitrary URLs with this factory's
 scheme id.  For example, invoking <tt>getObjectInstance()</tt> with
 <code>obj</code> set to null on an LDAP URL context factory would return a
 context that can resolve LDAP URLs
 such as "ldap://ldap.wiz.com/o=wiz,c=us" and
 "ldap://ldap.umich.edu/o=umich,c=us".
 <li>
 If <code>obj</code> is a URL string, create an object (typically a context)
 identified by the URL.  For example, suppose this is an LDAP URL context
 factory.  If <code>obj</code> is "ldap://ldap.wiz.com/o=wiz,c=us",
 getObjectInstance() would return the context named by the distinguished
 name "o=wiz, c=us" at the LDAP server ldap.wiz.com.  This context can
 then be used to resolve LDAP names (such as "cn=George")
 relative to that context.
 <li>
 If <code>obj</code> is an array of URL strings, the assumption is that the
 URLs are equivalent in terms of the context to which they refer.
 Verification of whether the URLs are, or need to be, equivalent is up
 to the context factory. The order of the URLs in the array is
 not significant.
 The object returned by getObjectInstance() is like that of the single
 URL case.  It is the object named by the URLs.
 <li>
 If <code>obj</code> is of any other type, the behavior of
 <tt>getObjectInstance()</tt> is determined by the context factory
 implementation.
 </ol>

 <p>
 The <tt>name</tt> and <tt>environment</tt> parameters
 are owned by the caller.
 The implementation will not modify these objects or keep references
 to them, although it may keep references to clones or copies.

 <p>
 <b>Name and Context Parameters.</b> &nbsp;&nbsp;&nbsp;
 <a name=NAMECTX></a>

 The <code>name</code> and <code>nameCtx</code> parameters may
 optionally be used to specify the name of the object being created.
 <code>name</code> is the name of the object, relative to context
 <code>nameCtx</code>.
 If there are several possible contexts from which the object
 could be named -- as will often be the case -- it is up to
 the caller to select one.  A good rule of thumb is to select the
 "deepest" context available.
 If <code>nameCtx</code> is null, <code>name</code> is relative
 to the default initial context.  If no name is being specified, the
 <code>name</code> parameter should be null.
 If a factory uses <code>nameCtx</code> it should synchronize its use
 against concurrent access, since context implementations are not
 guaranteed to be thread-safe.
 <p><DD><DL>
<DT><B>Parameters:</B><DD><CODE>obj</CODE> - The possibly null object containing location or reference 
 		information that can be used in creating an object.<DD><CODE>name</CODE> - The name of this object relative to <code>nameCtx</code>,
		or null if no name is specified.<DD><CODE>nameCtx</CODE> - The context relative to which the <code>name</code>
		parameter is specified, or null if <code>name</code> is
		relative to the default initial context.<DD><CODE>environment</CODE> - The possibly null environment that is used in
 		creating the object.<DT><B>Returns:</B><DD>The object created; null if an object cannot be created.<DT><B>Throws:</B><DD><CODE><A HREF="../../../java/lang/Exception.html">Exception</A></CODE> - if this object factory encountered an exception
 while attempting to create an object, and no other object factories are
 to be tried.<DT><B>See Also: </B><DD><A HREF="../../../javax/naming/spi/NamingManager.html#getObjectInstance(java.lang.Object, javax.naming.Name, javax.naming.Context, java.util.Hashtable)"><CODE>NamingManager.getObjectInstance(java.lang.Object, javax.naming.Name, javax.naming.Context, java.util.Hashtable)</CODE></A>, 
<A HREF="../../../javax/naming/spi/NamingManager.html#getURLContext(java.lang.String, java.util.Hashtable)"><CODE>NamingManager.getURLContext(java.lang.String, java.util.Hashtable)</CODE></A></DL>
</DD>
</DL>
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