/* JFox, the OpenSource J2EE Application Server
 *
 * Distributable under GNU LGPL license by gun.org
 * more details please visit http://www.huihoo.org/jfox
 */

package org.jfox.jndi;

import java.io.IOException;
import java.io.Serializable;
import java.rmi.MarshalledObject;
import java.rmi.RemoteException;
import java.util.Hashtable;
import java.util.List;
import javax.naming.Binding;
import javax.naming.CompoundName;
import javax.naming.Context;
import javax.naming.ContextNotEmptyException;
import javax.naming.InitialContext;
import javax.naming.InvalidNameException;
import javax.naming.LinkRef;
import javax.naming.Name;
import javax.naming.NameAlreadyBoundException;
import javax.naming.NameClassPair;
import javax.naming.NameNotFoundException;
import javax.naming.NameParser;
import javax.naming.NamingEnumeration;
import javax.naming.NamingException;
import javax.naming.NotContextException;
import javax.naming.OperationNotSupportedException;
import javax.naming.Reference;
import javax.naming.Referenceable;
import javax.naming.directory.Attributes;
import javax.naming.directory.DirContext;
import javax.naming.directory.InvalidAttributesException;
import javax.naming.spi.NamingManager;

import org.jfox.jndi.enc.EnterpriseContextFactory;

/**
 * @author <a href="mailto:young_yy@hotmail.com">Young Yang</a>
 */

public class ContextImpl implements Context, Serializable {
    /**
     * environment of this Context
     */
    private Hashtable env = new Hashtable();

    /**
     * 该 context 名字空间，如：/ , /test
     */
    private Name prefix;

    private NameParserImpl parser = NameParserImpl.getInstance();

    // NamingService stub
    private NamingService server;

    public ContextImpl(Name prefix, Hashtable env) throws NamingException {
        init(prefix, env);
    }

    public ContextImpl(String prefix, Hashtable env) throws NamingException {
        Name _prefix = null;
        if(prefix == null || prefix.trim().length() == 0) {
            _prefix = parser.parse("/");
        }
        else {
            _prefix = parser.parse(prefix.trim());
        }

        init(_prefix, env);

    }

    private void init(Name prefix, Hashtable env) throws NamingException {
        if(env == null) {
            env = JNDIProperties.getDefaultEnvironment();
        }
        this.env = (Hashtable) env.clone();

        /*
        URL providerUri = null;
        try {
          providerUri = JndiURL.getURL(this,(String)env.get(Context.PROVIDER_URL));
        }
        catch(MalformedURLException e){
          throw new NamingException("Conext initializing error ! Context.PROVIDER_URL = " + env.get(Context.PROVIDER_URL));
        }
        */

        server = ServiceLocator.getNamingService((String) env.get(Context.PROVIDER_URL));
        if(prefix == null || prefix.toString().trim().length() == 0) {
            this.prefix = parser.parse("/");
        }
        else {
            this.prefix = prefix;
        }

        // bound root Context as "/";
        try {
            if(this.prefix.toString().equals("/") && !server.isBound(prefix)) {
                this.bind(prefix, this);
            }
        }
        catch(RemoteException e) {
            throw new NamingException(e.getMessage());
        }
    }


    /**
     * Retrieves the named object.
     * 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 #lookup(String)
     * @see #lookupLink(Name)
     */
    public Object lookup(Name name) throws NamingException {
        if(name.isEmpty()) { // empty name will return a new context
            return new ContextImpl(this.getNameInNamespace(), this.getEnvironment());
        }

        // check enc
        if(EnterpriseContextFactory.isEnterpriseContext(name)) {
            Context ctx = (Context) lookup(EnterpriseContextFactory.ENC_JNDI_NAME);
            return ctx.lookup(EnterpriseContextFactory.getEnterpriseContextSuffix(name));
        }

        try {
            Name absoluteName = getAbsoluteName(name);
            Object obj = server.lookup(absoluteName);
            Object ret = obj;
            if(obj instanceof MarshalledObject) {
                ret = ((MarshalledObject) obj).get();
            }
            else if(obj instanceof Reference) { // common reference
                // Dereference object
                if(obj instanceof LinkRef) { // link ref
                    String ref = ((LinkRef) obj).getLinkName();
                    return new InitialContext(env).lookup(ref);
                }
                else { // other Reference, must use ObjectFactory.getObjectInstance
                    ret = NamingManager.getObjectInstance(obj, absoluteName, this, env);
                }
            }

            return ret;
        }
        catch(NamingException e) {
            throw e;
        }
        catch(Exception ex) {
            ex.printStackTrace();
            throw new NamingException(ex.toString());
        }

    }

    /**
     * Retrieves the named object.
     * See {@link #lookup(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
     */
    public Object lookup(String name) throws NamingException {
        return lookup(parser.parse(name));
    }

    /**
     * Binds a name to an object.
     * All intermediate contexts and the target context (that named by all
     * but terminal atomic component of the name) must already exist.
     *
     * @param name the name to bind; may not be empty
     * @param obj  the object to bind; possibly null
     * @throws	NameAlreadyBoundException if name is already bound
     * @throws	InvalidAttributesException if object did not supply all mandatory attributes
     * @throws	NamingException if a naming exception is encountered
     * @see #bind(String, Object)
     * @see #rebind(Name, Object)
     * @see DirContext#bind(Name, Object,
            *      Attributes)
     */
    public void bind(Name name, Object obj) throws NamingException {
        if(name.isEmpty()) {
            throw new InvalidNameException(name.toString());
        }

        String classname = null;
        if(obj instanceof Referenceable) { // get the reference first
            obj = ((Referenceable) obj).getReference();
        }
        if(obj instanceof Reference) {
            classname = ((Reference) obj).getClassName();
        }
        else {
            classname = obj.getClass().getName();
//      if(!(obj instanceof Remote)){ // not a remote class , let it be

            try {
                // if the object is a remote object, MarshalledObject is the stub
                obj = new MarshalledObject(obj);
            }
            catch(IOException e) {
                throw new NamingException(e.toString());
            }

//      }
        }
        try {
            server.bind(this, getAbsoluteName(name), obj, classname);
        }
        catch(RemoteException e) {
            throw new NamingException(e.toString());
        }

    }

    /**
     * Binds a name to an object.
     * See {@link #bind(Name, Object)} for details.
     *
     * @param name the name to bind; may not be empty
     * @param obj  the object to bind; possibly null
     * @throws	NameAlreadyBoundException if name is already bound
     * @throws	InvalidAttributesException if object did not supply all mandatory attributes
     * @throws	NamingException if a naming exception is encountered
     */
    public void bind(String name, Object obj) throws NamingException {
        bind(parser.parse(name), obj);
    }

    /**
     * Binds a name to an object, overwriting any existing binding.
     * All intermediate contexts and the target context (that named by all
     * but terminal atomic component of the name) must already exist.
     * <p/>
     * <p> If the object is a <tt>DirContext</tt>, any existing attributes
     * associated with the name are replaced with those of the object.
     * Otherwise, any existing attributes associated with the name remain
     * unchanged.
     *
     * @param name the name to bind; may not be empty
     * @param obj  the object to bind; possibly null
     * @throws	InvalidAttributesException if object did not supply all mandatory attributes
     * @throws	NamingException if a naming exception is encountered
     * @see #rebind(String, Object)
     * @see #bind(Name, Object)
     * @see DirContext#rebind(Name, Object,
            *      Attributes)
     * @see DirContext
     */
    public void rebind(Name name, Object obj) throws NamingException {
        if(name.isEmpty() || name.toString().trim().equals("/")) { // Empty names are not allowed
            throw new InvalidNameException(name.toString());
        }

        String classname = null;
        if(obj instanceof Referenceable) { // get the reference first
            obj = ((Referenceable) obj).getReference();
        }
        if(obj instanceof Reference) {
            classname = ((Reference) obj).getClassName();
        }
        else {
            classname = obj.getClass().getName();
            try {
                if(!(obj instanceof MarshalledObject)) {
                    obj = new MarshalledObject(obj);
                }
            }
            catch(IOException e) {
                throw new NamingException(e.toString());
            }
        }

        try {
//      System.out.println("server.rebind: " + getAbsoluteName(name));
            server.rebind(this, getAbsoluteName(name), obj, classname);
        }
        catch(RemoteException e) {
            e.printStackTrace();
            throw new NamingException(e.toString());
        }

    }

    /**
     * Binds a name to an object, overwriting any existing binding.
     * See {@link #rebind(Name, Object)} for details.
     *
     * @param name the name to bind; may not be empty
     * @param obj  the object to bind; possibly null
     * @throws	InvalidAttributesException if object did not supply all mandatory attributes
     * @throws	NamingException if a naming exception is encountered
     */
    public void rebind(String name, Object obj) throws NamingException {
        rebind(parser.parse(name), obj);
    }

    /**
     * Unbinds the named object.
     * Removes the terminal atomic name in <code>name</code>
     * from the target context--that named by all but the terminal
     * atomic part of <code>name</code>.
     * <p/>
     * <p> This method is idempotent.
     * It succeeds even if the terminal atomic name
     * is not bound in the target context, but throws
     * <tt>NameNotFoundException</tt>
     * if any of the intermediate contexts do not exist.
     * <p/>
     * <p> Any attributes associated with the name are removed.
     * Intermediate contexts are not changed.
     *
     * @param name the name to unbind; may not be empty
     * @throws	NameNotFoundException if an intermediate context does not exist
     * @throws	NamingException if a naming exception is encountered
     * @see #unbind(String)
     */
    public void unbind(Name name) throws NamingException {
        if(name.isEmpty() || name.toString().trim().equals("/")) {
            throw new InvalidNameException(name.toString());
        }
        try {
            Name absoluteName = getAbsoluteName(name);
            server.unbind(this, absoluteName);
        }
        catch(RemoteException ex) {
            throw new NamingException(ex.toString());
        }

    }

    /**
     * Unbinds the named object.
     * See {@link #unbind(Name)} for details.
     *
     * @param name the name to unbind; may not be empty
     * @throws	NameNotFoundException if an intermediate context does not exist
     * @throws	NamingException if a naming exception is encountered
     */
    public void unbind(String name) throws NamingException {
        unbind(parser.parse(name));
    }

    /**
     * Binds a new name to the object bound to an old name, and unbinds
     * the old name.  Both names are relative to this context.
     * Any attributes associated with the old name become associated
     * with the new name.
     * Intermediate contexts of the old name are not changed.
     *
     * @param oldName the name of the existing binding; may not be empty
     * @param newName the name of the new binding; may not be empty
     * @throws	NameAlreadyBoundException if <tt>newName</tt> is already bound
     * @throws	NamingException if a naming exception is encountered
     * @see #rename(String, String)
     * @see #bind(Name, Object)
     * @see #rebind(Name, Object)
     */
    public void rename(Name oldName, Name newName) throws NamingException {
        if(oldName.isEmpty() || oldName.toString().trim().equals("/") ||
                newName.isEmpty() || newName.toString().trim().equals("/")) {
            throw new InvalidNameException("oldName: " + oldName.toString() + ", newName: " + newName);
        }
        try {
            Object obj = server.lookup(oldName);
            bind(newName, obj);
        }
        catch(RemoteException e) {
            throw new NamingException(e.toString());
        }

        unbind(oldName);
    }

    /**
     * Binds a new name to the object bound to an old name, and unbinds
     * the old name.
     * See {@link #rename(Name, Name)} for details.
     *
     * @param oldName the name of the existing binding; may not be empty
     * @param newName the name of the new binding; may not be empty
     * @throws	NameAlreadyBoundException if <tt>newName</tt> is already bound
     * @throws	NamingException if a naming exception is encountered
     */
    public void rename(String oldName, String newName) throws NamingException {
        rename(parser.parse(oldName), parser.parse(newName));
    }

    /**
     * Enumerates the names bound in the named context, along with the
     * class names of objects bound to them.
     * The contents of any subcontexts are not included.
     * <p/>
     * <p> If a binding is added to or removed from this context,
     * its effect on an enumeration previously returned is undefined.
     *
     * @param name the name of the context to list
     * @return	an enumeration of the names and class names of the
     * bindings in this context.  Each element of the
     * enumeration is of type <tt>NameClassPair</tt>.
     * @throws	NamingException if a naming exception is encountered
     * @see #list(String)
     * @see #listBindings(Name)
     * @see NameClassPair
     */
    public NamingEnumeration list(Name name) throws NamingException {
        try {
            List list = server.list(this, getAbsoluteName(name));
            return new NamingEnumerationImpl(list);
        }
        catch(RemoteException ex) {
            throw new NamingException(ex.toString());
        }
    }

    /**
     * Enumerates the names bound in the named context, along with the
     * class names of objects bound to them.
     * See {@link #list(Name)} for details.
     *
     * @param name the name of the context to list
     * @return	an enumeration of the names and class names of the
     * bindings in this context.  Each element of the
     * enumeration is of type <tt>NameClassPair</tt>.
     * @throws	NamingException if a naming exception is encountered
     */
    public NamingEnumeration list(String name) throws NamingException {
        return list(parser.parse(name));
    }

    /**
     * Enumerates the names bound in the named context, along with the
     * objects bound to them.
     * The contents of any subcontexts are not included.
     * <p/>
     * <p> If a binding is added to or removed from this context,
     * its effect on an enumeration previously returned is undefined.
     *
     * @param name the name of the context to list
     * @return	an enumeration of the bindings in this context.
     * Each element of the enumeration is of type
     * <tt>Binding</tt>.
     * @throws	NamingException if a naming exception is encountered
     * @see #listBindings(String)
     * @see #list(Name)
     * @see Binding
     */
    public NamingEnumeration listBindings(Name name) throws NamingException {
        try {
            List list = server.listBindings(this, getAbsoluteName(name));
            return new NamingEnumerationImpl(list);
        }
        catch(RemoteException ex) {
            throw new NamingException(ex.toString());
        }

    }

    /**
     * Enumerates the names bound in the named context, along with the
     * objects bound to them.
     * See {@link #listBindings(Name)} for details.
     *
     * @param name the name of the context to list
     * @return	an enumeration of the bindings in this context.
     * Each element of the enumeration is of type
     * <tt>Binding</tt>.
     * @throws	NamingException if a naming exception is encountered
     */
    public NamingEnumeration listBindings(String name) throws NamingException {
        return listBindings(parser.parse(name));
    }

    /**
     * Destroys the named context and removes it from the namespace.
     * Any attributes associated with the name are also removed.
     * Intermediate contexts are not destroyed.
     * <p/>
     * <p> This method is idempotent.
     * It succeeds even if the terminal atomic name
     * is not bound in the target context, but throws
     * <tt>NameNotFoundException</tt>
     * if any of the intermediate contexts do not exist.
     * <p/>
     * <p> In a federated naming system, a context from one naming system
     * may be bound to a name in another.  One can subsequently
     * look up and perform operations on the foreign context using a
     * composite name.  However, an attempt destroy the context using
     * this composite name will fail with
     * <tt>NotContextException</tt>, because the foreign context is not
     * a "subcontext" of the context in which it is bound.
     * Instead, use <tt>unbind()</tt> to remove the
     * binding of the foreign context.  Destroying the foreign context
     * requires that the <tt>destroySubcontext()</tt> be performed
     * on a context from the foreign context's "native" naming system.
     *
     * @param name the name of the context to be destroyed; may not be empty
     * @throws	NameNotFoundException if an intermediate context does not exist
     * @throws	NotContextException if the name is bound but does not name a
     * context, or does not name a context of the appropriate type
     * @throws	ContextNotEmptyException if the named context is not empty
     * @throws	NamingException if a naming exception is encountered
     * @see #destroySubcontext(String)
     */
    public void destroySubcontext(Name name) throws NamingException {
        if(name.isEmpty() || name.toString().trim().equals("/")) { // Empty names are not allowed
            throw new InvalidNameException(name.toString());
        }
        try {
            server.destroySubcontext(this, getAbsoluteName(name));
        }
        catch(RemoteException e) {
            throw new NamingException(e.toString());
        }

    }

    /**
     * Destroys the named context and removes it from the namespace.
     * See {@link #destroySubcontext(Name)} for details.
     *
     * @param name the name of the context to be destroyed; may not be empty
     * @throws	NameNotFoundException if an intermediate context does not exist
     * @throws	NotContextException if the name is bound but does not name a
     * context, or does not name a context of the appropriate type
     * @throws	ContextNotEmptyException if the named context is not empty
     * @throws	NamingException if a naming exception is encountered
     */
    public void destroySubcontext(String name) throws NamingException {
        destroySubcontext(parser.parse(name));
    }

    /**
     * Creates and binds a new context.
     * Creates a new context with the given name and binds it in
     * the target context (that named by all but terminal atomic
     * component of the name).  All intermediate contexts and the
     * target context must already exist.
     *
     * @param name the name of the context to create; may not be empty
     * @return	the newly created context
     * @throws	NameAlreadyBoundException if name is already bound
     * @throws	InvalidAttributesException if creation of the subcontext requires specification of
     * mandatory attributes
     * @throws	NamingException if a naming exception is encountered
     * @see #createSubcontext(String)
     * @see DirContext#createSubcontext
     */
    public Context createSubcontext(Name name) throws NamingException {
        if(name.isEmpty() || name.toString().trim().equals("/")) {
            throw new InvalidNameException(name.toString());
        }
        try {
            name = getAbsoluteName(name);
            return server.createSubcontext(this, name);
        }
        catch(RemoteException ex) {
            throw new NamingException(ex.toString());
        }

    }

    /**
     * Creates and binds a new context.
     * See {@link #createSubcontext(Name)} for details.
     *
     * @param name the name of the context to create; may not be empty
     * @return	the newly created context
     * @throws	NameAlreadyBoundException if name is already bound
     * @throws	InvalidAttributesException if creation of the subcontext requires specification of
     * mandatory attributes
     * @throws	NamingException if a naming exception is encountered
     */
    public Context createSubcontext(String name) throws NamingException {
        return createSubcontext(parser.parse(name));
    }

    /**
     * Retrieves the named object, following links except
     * for the terminal atomic component of the name.
     * If the object bound to <tt>name</tt> is not a link,
     * returns the object itself.
     *
     * @param name the name of the object to look up
     * @return	the object bound to <tt>name</tt>, not following the
     * terminal link (if any).
     * @throws	NamingException if a naming exception is encountered
     * @see #lookupLink(String)
     */
    public Object lookupLink(Name name) throws NamingException {
        return lookup(name);
    }

    /**
     * Retrieves the named object, following links except
     * for the terminal atomic component of the name.
     * See {@link #lookupLink(Name)} for details.
     *
     * @param name the name of the object to look up
     * @return	the object bound to <tt>name</tt>, not following the
     * terminal link (if any)
     * @throws	NamingException if a naming exception is encountered
     */
    public Object lookupLink(String name) throws NamingException {
        return lookupLink(parser.parse(name));
    }

    /**
     * Retrieves the parser associated with the named context.
     * In a federation of namespaces, different naming systems will
     * parse names differently.  This method allows an application
     * to get a parser for parsing names into their atomic components
     * using the naming convention of a particular naming system.
     * Within any single naming system, <tt>NameParser</tt> objects
     * returned by this method must be equal (using the <tt>equals()</tt>
     * test).
     *
     * @param name the name of the context from which to get the parser
     * @return	a name parser that can parse compound names into their atomic
     * components
     * @throws	NamingException if a naming exception is encountered
     * @see #getNameParser(String)
     * @see CompoundName
     */
    public NameParser getNameParser(Name name) throws NamingException {
        return parser;
    }

    /**
     * Retrieves the parser associated with the named context.
     * See {@link #getNameParser(Name)} for details.
     *
     * @param name the name of the context from which to get the parser
     * @return	a name parser that can parse compound names into their atomic
     * components
     * @throws	NamingException if a naming exception is encountered
     */
    public NameParser getNameParser(String name) throws NamingException {
        return parser;
    }

    /**
     * Composes the name of this context with a name relative to
     * this context.
     * Given a name (<code>name</code>) relative to this context, and
     * the name (<code>prefix</code>) of this context relative to one
     * of its ancestors, this method returns the composition of the
     * two names using the syntax appropriate for the naming
     * system(s) involved.  That is, if <code>name</code> names an
     * object relative to this context, the result is the name of the
     * same object, but relative to the ancestor context.  None of the
     * names may be null.
     * <p/>
     * For example, if this context is named "wiz.com" relative
     * to the initial context, then
     * <pre>
     * 	composeName("east", "wiz.com")	</pre>
     * might return <code>"east.wiz.com"</code>.
     * If instead this context is named "org/research", then
     * <pre>
     * 	composeName("user/jane", "org/research")	</pre>
     * might return <code>"org/research/user/jane"</code> while
     * <pre>
     * 	composeName("user/jane", "research")	</pre>
     * returns <code>"research/user/jane"</code>.
     *
     * @param name   a name relative to this context
     * @param prefix the name of this context relative to one of its ancestors
     * @return	the composition of <code>prefix</code> and <code>name</code>
     * @throws	NamingException if a naming exception is encountered
     * @see #composeName(String, String)
     */
    public Name composeName(Name name, Name prefix) throws NamingException {
        Name newName = (Name) (prefix.clone());
        newName.addAll(name);
        return newName;
    }

    /**
     * Composes the name of this context with a name relative to
     * this context.
     * See {@link #composeName(Name, Name)} for details.
     *
     * @param name   a name relative to this context
     * @param prefix the name of this context relative to one of its ancestors
     * @return	the composition of <code>prefix</code> and <code>name</code>
     * @throws	NamingException if a naming exception is encountered
     */
    public String composeName(String name, String prefix) throws NamingException {
        Name result = composeName(parser.parse(name), parser.parse(prefix));
        return result.toString();
    }

    /**
     * Adds a new environment property to the environment of this
     * context.  If the property already exists, its value is overwritten.
     * See class description for more details on environment properties.
     *
     * @param propName the name of the environment property to add; may not be null
     * @param propVal  the value of the property to add; may not be null
     * @return	the previous value of the property, or null if the property was
     * not in the environment before
     * @throws	NamingException if a naming exception is encountered
     * @see #getEnvironment()
     * @see #removeFromEnvironment(String)
     */
    public Object addToEnvironment(String propName, Object propVal)
            throws NamingException {

        return env.put(propName, propVal);
    }

    /**
     * Removes an environment property from the environment of this
     * context.  See class description for more details on environment
     * properties.
     *
     * @param propName the name of the environment property to remove; may not be null
     * @return	the previous value of the property, or null if the property was
     * not in the environment
     * @throws	NamingException if a naming exception is encountered
     * @see #getEnvironment()
     * @see #addToEnvironment(String, Object)
     */
    public Object removeFromEnvironment(String propName)
            throws NamingException {
        return env.remove(propName);
    }

    /**
     * Retrieves the environment in effect for this context.
     * See class description for more details on environment properties.
     * <p/>
     * <p> The caller should not make any changes to the object returned:
     * their effect on the context is undefined.
     * The environment of this context may be changed using
     * <tt>addToEnvironment()</tt> and <tt>removeFromEnvironment()</tt>.
     *
     * @return	the environment of this context; never null
     * @throws	NamingException if a naming exception is encountered
     * @see #addToEnvironment(String, Object)
     * @see #removeFromEnvironment(String)
     */
    public Hashtable getEnvironment() throws NamingException {
        return JNDIProperties.cloneEnvironment(env);
    }

    /**
     * Closes this context.
     * This method releases this context's resources immediately, instead of
     * waiting for them to be released automatically by the garbage collector.
     * <p/>
     * <p> This method is idempotent:  invoking it on a context that has
     * already been closed has no effect.  Invoking any other method
     * on a closed context is not allowed, and results in undefined behaviour.
     *
     * @throws	NamingException if a naming exception is encountered
     */
    public void close() throws NamingException {
        try {
            server.closeSubcontext(this, prefix);
//      server = null;
//      env = null;
        }
        catch(RemoteException e) {
            throw new NamingException(e.toString());
        }
    }

    /**
     * Retrieves the full name of this context within its own namespace.
     * <p/>
     * <p> Many naming services have a notion of a "full name" for objects
     * in their respective namespaces.  For example, an LDAP entry has
     * a distinguished name, and a DNS record has a fully qualified name.
     * This method allows the client application to retrieve this name.
     * The string returned by this method is not a JNDI composite name
     * and should not be passed directly to context methods.
     * In naming systems for which the notion of full name does not
     * make sense, <tt>OperationNotSupportedException</tt> is thrown.
     *
     * @return	this context's name in its own namespace; never null
     * @throws	OperationNotSupportedException if the naming system does
     * not have the notion of a full name
     * @throws	NamingException if a naming exception is encountered
     * @since 1.3
     */
    public String getNameInNamespace() throws NamingException {
        return prefix.toString();
    }

    private Name getAbsoluteName(Name name) throws NamingException {
        // 在 context 初始化的时候，把 / 绑定到 context
        if(name.startsWith(prefix)) return name;

        // like java://localhost:1099/a/b/c
        if(name.toString().indexOf("://") > 0) {
            name = name.getSuffix(3);
        }
        // like java:/a/b/c
        else if(name.toString().indexOf(":/") > 0) {
            name = name.getSuffix(1);
        }

        return composeName(name, prefix);
    }

}