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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
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 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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package javax.naming;

import java.util.Hashtable;
import javax.naming.spi.NamingManager;
import com.sun.naming.internal.ResourceManager;

This class is the starting context for performing naming operations.

All naming operations are relative to a context.
The initial context implements the Context interface and
provides the starting point for resolution of names.


When the initial context is constructed, its environment
is initialized with properties defined in the environment parameter
passed to the constructor, and in any
application resource files. In addition, a small number of standard JNDI properties may be specified as system properties or as applet parameters (through the use of Context.APPLET). These special properties are listed in the field detail sections of the Context and
LdapContext
interface documentation.

JNDI determines each property's value by merging
the values from the following two sources, in order:


The first occurrence of the property from the constructor's
environment parameter and (for appropriate properties) the applet
parameters and system properties.

The application resource files (jndi.properties).

For each property found in both of these two sources, or in
more than one application resource file, the property's value
is determined as follows.  If the property is
one of the standard JNDI properties that specify a list of JNDI
factories (see Context),
all of the values are
concatenated into a single colon-separated list.  For other
properties, only the first value found is used.
 The initial context implementation is determined at runtime. The default policy uses the environment property "java.naming.factory.initial", which contains the class name of the initial context factory. An exception to this policy is made when resolving URL strings, as described below. 

When a URL string (a String of the form
scheme_id:rest_of_name) is passed as a name parameter to
any method, a URL context factory for handling that scheme is
located and used to resolve the URL.  If no such factory is found,
the initial context specified by
"java.naming.factory.initial" is used.  Similarly, when a
CompositeName object whose first component is a URL string is passed as a name parameter to any method, a URL context factory is located and used to resolve the first name component. See NamingManager.getURLContext() for a description of how URL context factories are located. 

This default policy of locating the initial context and URL context
factories may be overridden
by calling
NamingManager.setInitialContextFactoryBuilder().

NoInitialContextException is thrown when an initial context cannot
be instantiated. This exception can be thrown during any interaction
with the InitialContext, not only when the InitialContext is constructed.
For example, the implementation of the initial context might lazily
retrieve the context only when actual methods are invoked on it.
The application should not have any dependency on when the existence
of an initial context is determined.

When the environment property "java.naming.factory.initial" is
non-null, the InitialContext constructor will attempt to create the
initial context specified therein. At that time, the initial context factory
involved might throw an exception if a problem is encountered. However,
it is provider implementation-dependent when it verifies and indicates
to the users of the initial context any environment property- or
connection- related problems. It can do so lazily--delaying until
an operation is performed on the context, or eagerly, at the time
the context is constructed.

An InitialContext instance is not synchronized against concurrent
access by multiple threads. Multiple threads each manipulating a
different InitialContext instance need not synchronize.
Threads that need to access a single InitialContext instance
concurrently should synchronize amongst themselves and provide the
necessary locking.
Author:
Rosanna Lee, Scott Seligman
See Also:
Context

     NamingManager.setInitialContextFactoryBuilder
Since:
JNDI 1.1 / Java 2 Platform, Standard Edition, v 1.3/**
 * This class is the starting context for performing naming operations.
 *<p>
 * All naming operations are relative to a context.
 * The initial context implements the Context interface and
 * provides the starting point for resolution of names.
 *<p>
 * <a name=ENVIRONMENT></a>
 * When the initial context is constructed, its environment
 * is initialized with properties defined in the environment parameter
 * passed to the constructor, and in any
 * <a href=Context.html#RESOURCEFILES>application resource files</a>.
 * In addition, a small number of standard JNDI properties may
 * be specified as system properties or as applet parameters
 * (through the use of {@link Context#APPLET}).
 * These special properties are listed in the field detail sections of the
 * <a href=Context.html#field_detail><tt>Context</tt></a> and
 * <a href=ldap/LdapContext.html#field_detail><tt>LdapContext</tt></a>
 * interface documentation.
 *<p>
 * JNDI determines each property's value by merging
 * the values from the following two sources, in order:
 * <ol>
 * <li>
 * The first occurrence of the property from the constructor's
 * environment parameter and (for appropriate properties) the applet
 * parameters and system properties.
 * <li>
 * The application resource files (<tt>jndi.properties</tt>).
 * </ol>
 * For each property found in both of these two sources, or in
 * more than one application resource file, the property's value
 * is determined as follows.  If the property is
 * one of the standard JNDI properties that specify a list of JNDI
 * factories (see <a href=Context.html#LISTPROPS><tt>Context</tt></a>),
 * all of the values are
 * concatenated into a single colon-separated list.  For other
 * properties, only the first value found is used.
 *
 *<p>
 * The initial context implementation is determined at runtime.
 * The default policy uses the environment property
 * "{@link Context#INITIAL_CONTEXT_FACTORY java.naming.factory.initial}",
 * which contains the class name of the initial context factory.
 * An exception to this policy is made when resolving URL strings, as described
 * below.
 *<p>
 * When a URL string (a <tt>String</tt> of the form
 * <em>scheme_id:rest_of_name</em>) is passed as a name parameter to
 * any method, a URL context factory for handling that scheme is
 * located and used to resolve the URL.  If no such factory is found,
 * the initial context specified by
 * <tt>"java.naming.factory.initial"</tt> is used.  Similarly, when a
 * <tt>CompositeName</tt> object whose first component is a URL string is
 * passed as a name parameter to any method, a URL context factory is
 * located and used to resolve the first name component.
 * See {@link NamingManager#getURLContext
 * <tt>NamingManager.getURLContext()</tt>} for a description of how URL
 * context factories are located.
 *<p>
 * This default policy of locating the initial context and URL context
 * factories may be overridden
 * by calling
 * <tt>NamingManager.setInitialContextFactoryBuilder()</tt>.
 *<p>
 * NoInitialContextException is thrown when an initial context cannot
 * be instantiated. This exception can be thrown during any interaction
 * with the InitialContext, not only when the InitialContext is constructed.
 * For example, the implementation of the initial context might lazily
 * retrieve the context only when actual methods are invoked on it.
 * The application should not have any dependency on when the existence
 * of an initial context is determined.
 *<p>
 * When the environment property "java.naming.factory.initial" is
 * non-null, the InitialContext constructor will attempt to create the
 * initial context specified therein. At that time, the initial context factory
 * involved might throw an exception if a problem is encountered. However,
 * it is provider implementation-dependent when it verifies and indicates
 * to the users of the initial context any environment property- or
 * connection- related problems. It can do so lazily--delaying until
 * an operation is performed on the context, or eagerly, at the time
 * the context is constructed.
 *<p>
 * An InitialContext instance is not synchronized against concurrent
 * access by multiple threads. Multiple threads each manipulating a
 * different InitialContext instance need not synchronize.
 * Threads that need to access a single InitialContext instance
 * concurrently should synchronize amongst themselves and provide the
 * necessary locking.
 *
 * @author Rosanna Lee
 * @author Scott Seligman
 *
 * @see Context
 * @see NamingManager#setInitialContextFactoryBuilder
 *      NamingManager.setInitialContextFactoryBuilder
 * @since JNDI 1.1 / Java 2 Platform, Standard Edition, v 1.3
 */

public class InitialContext implements Context {

    
The environment associated with this InitialContext.
It is initialized to null and is updated by the constructor
that accepts an environment or by the init() method.
See Also:
addToEnvironment
removeFromEnvironment
getEnvironment/**
     * The environment associated with this InitialContext.
     * It is initialized to null and is updated by the constructor
     * that accepts an environment or by the <tt>init()</tt> method.
     * @see #addToEnvironment
     * @see #removeFromEnvironment
     * @see #getEnvironment
     */
    protected Hashtable<Object,Object> myProps = null;

    
Field holding the result of calling NamingManager.getInitialContext().
It is set by getDefaultInitCtx() the first time getDefaultInitCtx()
is called. Subsequent invocations of getDefaultInitCtx() return
the value of defaultInitCtx.
See Also:
getDefaultInitCtx/**
     * Field holding the result of calling NamingManager.getInitialContext().
     * It is set by getDefaultInitCtx() the first time getDefaultInitCtx()
     * is called. Subsequent invocations of getDefaultInitCtx() return
     * the value of defaultInitCtx.
     * @see #getDefaultInitCtx
     */
    protected Context defaultInitCtx = null;

    
Field indicating whether the initial context has been obtained
by calling NamingManager.getInitialContext().
If true, its result is in defaultInitCtx.
/**
     * Field indicating whether the initial context has been obtained
     * by calling NamingManager.getInitialContext().
     * If true, its result is in <code>defaultInitCtx</code>.
     */
    protected boolean gotDefault = false;

    
Constructs an initial context with the option of not
initializing it.  This may be used by a constructor in
a subclass when the value of the environment parameter
is not yet known at the time the InitialContext
constructor is called.  The subclass's constructor will
call this constructor, compute the value of the environment,
and then call init() before returning.
Params:
lazy – 
         true means do not initialize the initial context; false
         is equivalent to calling new InitialContext()
Throws:
NamingException – if a naming exception is encountered
See Also:
init(Hashtable<?,?>)
Since:
1.3/**
     * Constructs an initial context with the option of not
     * initializing it.  This may be used by a constructor in
     * a subclass when the value of the environment parameter
     * is not yet known at the time the <tt>InitialContext</tt>
     * constructor is called.  The subclass's constructor will
     * call this constructor, compute the value of the environment,
     * and then call <tt>init()</tt> before returning.
     *
     * @param lazy
     *          true means do not initialize the initial context; false
     *          is equivalent to calling <tt>new InitialContext()</tt>
     * @throws  NamingException if a naming exception is encountered
     *
     * @see #init(Hashtable)
     * @since 1.3
     */
    protected InitialContext(boolean lazy) throws NamingException {
        if (!lazy) {
            init(null);
        }
    }

    
Constructs an initial context.
No environment properties are supplied.
Equivalent to new InitialContext(null).
Throws:
NamingException – if a naming exception is encountered
See Also:
InitialContext(Hashtable<?,?>)/**
     * Constructs an initial context.
     * No environment properties are supplied.
     * Equivalent to <tt>new InitialContext(null)</tt>.
     *
     * @throws  NamingException if a naming exception is encountered
     *
     * @see #InitialContext(Hashtable)
     */
    public InitialContext() throws NamingException {
        init(null);
    }

    
Constructs an initial context using the supplied environment.
Environment properties are discussed in the class description.
 This constructor will not modify environment
or save a reference to it, but may save a clone.
Params:
environment – 
         environment used to create the initial context.
         Null indicates an empty environment.
Throws:
NamingException – if a naming exception is encountered/**
     * Constructs an initial context using the supplied environment.
     * Environment properties are discussed in the class description.
     *
     * <p> This constructor will not modify <tt>environment</tt>
     * or save a reference to it, but may save a clone.
     *
     * @param environment
     *          environment used to create the initial context.
     *          Null indicates an empty environment.
     *
     * @throws  NamingException if a naming exception is encountered
     */
    public InitialContext(Hashtable<?,?> environment)
        throws NamingException
    {
        if (environment != null) {
            environment = (Hashtable)environment.clone();
        }
        init(environment);
    }

    
Initializes the initial context using the supplied environment.
Environment properties are discussed in the class description.
 This method will modify environment and save
a reference to it.  The caller may no longer modify it.
Params:
environment – 
         environment used to create the initial context.
         Null indicates an empty environment.
Throws:
NamingException – if a naming exception is encountered
See Also:
InitialContext(boolean)
Since:
1.3/**
     * Initializes the initial context using the supplied environment.
     * Environment properties are discussed in the class description.
     *
     * <p> This method will modify <tt>environment</tt> and save
     * a reference to it.  The caller may no longer modify it.
     *
     * @param environment
     *          environment used to create the initial context.
     *          Null indicates an empty environment.
     *
     * @throws  NamingException if a naming exception is encountered
     *
     * @see #InitialContext(boolean)
     * @since 1.3
     */
    protected void init(Hashtable<?,?> environment)
        throws NamingException
    {
        myProps = ResourceManager.getInitialEnvironment(environment);

        if (myProps.get(Context.INITIAL_CONTEXT_FACTORY) != null) {
            // user has specified initial context factory; try to get it
            getDefaultInitCtx();
        }
    }

    
A static method to retrieve the named object.
This is a shortcut method equivalent to invoking:


       InitialContext ic = new InitialContext();
       Object obj = ic.lookup();

 If name is empty, returns a new instance of this context
(which represents the same naming context as this context, but its
environment may be modified independently and it may be accessed
concurrently).
Params:
name – 
         the name of the object to look up
Throws:
NamingException – if a naming exception is encountered
See Also:
doLookup(String)
lookup(Name)
Returns:
 the object bound to name
Since:
1.6/**
     * A static method to retrieve the named object.
     * This is a shortcut method equivalent to invoking:
     * <p>
     * <code>
     *        InitialContext ic = new InitialContext();
     *        Object obj = ic.lookup();
     * </code>
     * <p> If <tt>name</tt> is empty, returns a new instance of this context
     * (which represents the same naming context as this context, but its
     * environment may be modified independently and it may be accessed
     * concurrently).
     *
     * @param name
     *          the name of the object to look up
     * @return  the object bound to <tt>name</tt>
     * @throws  NamingException if a naming exception is encountered
     *
     * @see #doLookup(String)
     * @see #lookup(Name)
     * @since 1.6
     */
    public static <T> T doLookup(Name name)
        throws NamingException {
        return (T) (new InitialContext()).lookup(name);
    }

   
A static method to retrieve the named object. See doLookup(Name) for details. 
Params:
name – 
         the name of the object to look up
Throws:
NamingException – if a naming exception is encountered
Returns:
 the object bound to name
Since:
1.6/**
     * A static method to retrieve the named object.
     * See {@link #doLookup(Name)} for details.
     * @param name
     *          the name of the object to look up
     * @return  the object bound to <tt>name</tt>
     * @throws  NamingException if a naming exception is encountered
      * @since 1.6
     */
    public static <T> T doLookup(String name)
        throws NamingException {
        return (T) (new InitialContext()).lookup(name);
    }

    private static String getURLScheme(String str) {
        int colon_posn = str.indexOf(':');
        int slash_posn = str.indexOf('/');

        if (colon_posn > 0 && (slash_posn == -1 || colon_posn < slash_posn))
            return str.substring(0, colon_posn);
        return null;
    }

    
Retrieves the initial context by calling
NamingManager.getInitialContext()
and cache it in defaultInitCtx.
Set gotDefault so that we know we've tried this before.
Throws:
NoInitialContextException – If cannot find an initial context.
NamingException – If a naming exception was encountered.
Returns:
The non-null cached initial context./**
     * Retrieves the initial context by calling
     * <code>NamingManager.getInitialContext()</code>
     * and cache it in defaultInitCtx.
     * Set <code>gotDefault</code> so that we know we've tried this before.
     * @return The non-null cached initial context.
     * @exception NoInitialContextException If cannot find an initial context.
     * @exception NamingException If a naming exception was encountered.
     */
    protected Context getDefaultInitCtx() throws NamingException{
        if (!gotDefault) {
            defaultInitCtx = NamingManager.getInitialContext(myProps);
            gotDefault = true;
        }
        if (defaultInitCtx == null)
            throw new NoInitialContextException();

        return defaultInitCtx;
    }

    
Retrieves a context for resolving the string name name.
If name name is a URL string, then attempt
to find a URL context for it. If none is found, or if
name is not a URL string, then return
getDefaultInitCtx().

See getURLOrDefaultInitCtx(Name) for description
of how a subclass should use this method.
Params:
name – The non-null name for which to get the context.
Throws:
NoInitialContextException – If cannot find an initial context.
NamingException – In a naming exception is encountered.
See Also:
NamingManager.getURLContext
Returns:
A URL context for name or the cached
        initial context. The result cannot be null./**
     * Retrieves a context for resolving the string name <code>name</code>.
     * If <code>name</code> name is a URL string, then attempt
     * to find a URL context for it. If none is found, or if
     * <code>name</code> is not a URL string, then return
     * <code>getDefaultInitCtx()</code>.
     *<p>
     * See getURLOrDefaultInitCtx(Name) for description
     * of how a subclass should use this method.
     * @param name The non-null name for which to get the context.
     * @return A URL context for <code>name</code> or the cached
     *         initial context. The result cannot be null.
     * @exception NoInitialContextException If cannot find an initial context.
     * @exception NamingException In a naming exception is encountered.
     * @see javax.naming.spi.NamingManager#getURLContext
     */
    protected Context getURLOrDefaultInitCtx(String name)
        throws NamingException {
        if (NamingManager.hasInitialContextFactoryBuilder()) {
            return getDefaultInitCtx();
        }
        String scheme = getURLScheme(name);
        if (scheme != null) {
            Context ctx = NamingManager.getURLContext(scheme, myProps);
            if (ctx != null) {
                return ctx;
            }
        }
        return getDefaultInitCtx();
    }

    
Retrieves a context for resolving name.
If the first component of name name is a URL string,
then attempt to find a URL context for it. If none is found, or if
the first component of name is not a URL string,
then return getDefaultInitCtx().

When creating a subclass of InitialContext, use this method as
follows.
Define a new method that uses this method to get an initial
context of the desired subclass.
protected XXXContext getURLOrDefaultInitXXXCtx(Name name)
throws NamingException {
 Context answer = getURLOrDefaultInitCtx(name);
 if (!(answer instanceof XXXContext)) {
   if (answer == null) {
     throw new NoInitialContextException();
   } else {
     throw new NotContextException("Not an XXXContext");
   }
 }
 return (XXXContext)answer;
}

When providing implementations for the new methods in the subclass,
use this newly defined method to get the initial context.
public Object XXXMethod1(Name name, ...) {
 throws NamingException {
   return getURLOrDefaultInitXXXCtx(name).XXXMethod1(name, ...);
}

Params:
name – The non-null name for which to get the context.
Throws:
NoInitialContextException – If cannot find an initial context.
NamingException – In a naming exception is encountered.
See Also:
NamingManager.getURLContext
Returns:
A URL context for name or the cached
        initial context. The result cannot be null./**
     * Retrieves a context for resolving <code>name</code>.
     * If the first component of <code>name</code> name is a URL string,
     * then attempt to find a URL context for it. If none is found, or if
     * the first component of <code>name</code> is not a URL string,
     * then return <code>getDefaultInitCtx()</code>.
     *<p>
     * When creating a subclass of InitialContext, use this method as
     * follows.
     * Define a new method that uses this method to get an initial
     * context of the desired subclass.
     * <p><blockquote><pre>
     * protected XXXContext getURLOrDefaultInitXXXCtx(Name name)
     * throws NamingException {
     *  Context answer = getURLOrDefaultInitCtx(name);
     *  if (!(answer instanceof XXXContext)) {
     *    if (answer == null) {
     *      throw new NoInitialContextException();
     *    } else {
     *      throw new NotContextException("Not an XXXContext");
     *    }
     *  }
     *  return (XXXContext)answer;
     * }
     * </pre></blockquote>
     * When providing implementations for the new methods in the subclass,
     * use this newly defined method to get the initial context.
     * <p><blockquote><pre>
     * public Object XXXMethod1(Name name, ...) {
     *  throws NamingException {
     *    return getURLOrDefaultInitXXXCtx(name).XXXMethod1(name, ...);
     * }
     * </pre></blockquote>
     *
     * @param name The non-null name for which to get the context.
     * @return A URL context for <code>name</code> or the cached
     *         initial context. The result cannot be null.
     * @exception NoInitialContextException If cannot find an initial context.
     * @exception NamingException In a naming exception is encountered.
     *
     * @see javax.naming.spi.NamingManager#getURLContext
     */
    protected Context getURLOrDefaultInitCtx(Name name)
        throws NamingException {
        if (NamingManager.hasInitialContextFactoryBuilder()) {
            return getDefaultInitCtx();
        }
        if (name.size() > 0) {
            String first = name.get(0);
            String scheme = getURLScheme(first);
            if (scheme != null) {
                Context ctx = NamingManager.getURLContext(scheme, myProps);
                if (ctx != null) {
                    return ctx;
                }
            }
        }
        return getDefaultInitCtx();
    }

// Context methods
// Most Javadoc is deferred to the Context interface.

    public Object lookup(String name) throws NamingException {
        return getURLOrDefaultInitCtx(name).lookup(name);
    }

    public Object lookup(Name name) throws NamingException {
        return getURLOrDefaultInitCtx(name).lookup(name);
    }

    public void bind(String name, Object obj) throws NamingException {
        getURLOrDefaultInitCtx(name).bind(name, obj);
    }

    public void bind(Name name, Object obj) throws NamingException {
        getURLOrDefaultInitCtx(name).bind(name, obj);
    }

    public void rebind(String name, Object obj) throws NamingException {
        getURLOrDefaultInitCtx(name).rebind(name, obj);
    }

    public void rebind(Name name, Object obj) throws NamingException {
        getURLOrDefaultInitCtx(name).rebind(name, obj);
    }

    public void unbind(String name) throws NamingException  {
        getURLOrDefaultInitCtx(name).unbind(name);
    }

    public void unbind(Name name) throws NamingException  {
        getURLOrDefaultInitCtx(name).unbind(name);
    }

    public void rename(String oldName, String newName) throws NamingException {
        getURLOrDefaultInitCtx(oldName).rename(oldName, newName);
    }

    public void rename(Name oldName, Name newName)
        throws NamingException
    {
        getURLOrDefaultInitCtx(oldName).rename(oldName, newName);
    }

    public NamingEnumeration<NameClassPair> list(String name)
        throws NamingException
    {
        return (getURLOrDefaultInitCtx(name).list(name));
    }

    public NamingEnumeration<NameClassPair> list(Name name)
        throws NamingException
    {
        return (getURLOrDefaultInitCtx(name).list(name));
    }

    public NamingEnumeration<Binding> listBindings(String name)
            throws NamingException  {
        return getURLOrDefaultInitCtx(name).listBindings(name);
    }

    public NamingEnumeration<Binding> listBindings(Name name)
            throws NamingException  {
        return getURLOrDefaultInitCtx(name).listBindings(name);
    }

    public void destroySubcontext(String name) throws NamingException  {
        getURLOrDefaultInitCtx(name).destroySubcontext(name);
    }

    public void destroySubcontext(Name name) throws NamingException  {
        getURLOrDefaultInitCtx(name).destroySubcontext(name);
    }

    public Context createSubcontext(String name) throws NamingException  {
        return getURLOrDefaultInitCtx(name).createSubcontext(name);
    }

    public Context createSubcontext(Name name) throws NamingException  {
        return getURLOrDefaultInitCtx(name).createSubcontext(name);
    }

    public Object lookupLink(String name) throws NamingException  {
        return getURLOrDefaultInitCtx(name).lookupLink(name);
    }

    public Object lookupLink(Name name) throws NamingException {
        return getURLOrDefaultInitCtx(name).lookupLink(name);
    }

    public NameParser getNameParser(String name) throws NamingException {
        return getURLOrDefaultInitCtx(name).getNameParser(name);
    }

    public NameParser getNameParser(Name name) throws NamingException {
        return getURLOrDefaultInitCtx(name).getNameParser(name);
    }

    
Composes the name of this context with a name relative to
this context.
Since an initial context may never be named relative
to any context other than itself, the value of the
prefix parameter must be an empty name ("").
/**
     * Composes the name of this context with a name relative to
     * this context.
     * Since an initial context may never be named relative
     * to any context other than itself, the value of the
     * <tt>prefix</tt> parameter must be an empty name (<tt>""</tt>).
     */
    public String composeName(String name, String prefix)
            throws NamingException {
        return name;
    }

    
Composes the name of this context with a name relative to
this context.
Since an initial context may never be named relative
to any context other than itself, the value of the
prefix parameter must be an empty name.
/**
     * Composes the name of this context with a name relative to
     * this context.
     * Since an initial context may never be named relative
     * to any context other than itself, the value of the
     * <tt>prefix</tt> parameter must be an empty name.
     */
    public Name composeName(Name name, Name prefix)
        throws NamingException
    {
        return (Name)name.clone();
    }

    public Object addToEnvironment(String propName, Object propVal)
            throws NamingException {
        myProps.put(propName, propVal);
        return getDefaultInitCtx().addToEnvironment(propName, propVal);
    }

    public Object removeFromEnvironment(String propName)
            throws NamingException {
        myProps.remove(propName);
        return getDefaultInitCtx().removeFromEnvironment(propName);
    }

    public Hashtable<?,?> getEnvironment() throws NamingException {
        return getDefaultInitCtx().getEnvironment();
    }

    public void close() throws NamingException {
        myProps = null;
        if (defaultInitCtx != null) {
            defaultInitCtx.close();
            defaultInitCtx = null;
        }
        gotDefault = false;
    }

    public String getNameInNamespace() throws NamingException {
        return getDefaultInitCtx().getNameInNamespace();
    }
};