namingcontext.java

业界著名的tomcat服务器的最新6.0的源代码。

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 * 
 *      http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */ 


package org.apache.naming;

import java.util.HashMap;
import java.util.Hashtable;
import java.util.Enumeration;
import javax.naming.Context;
import javax.naming.Name;
import javax.naming.LinkRef;
import javax.naming.CompositeName;
import javax.naming.NameParser;
import javax.naming.Referenceable;
import javax.naming.Reference;
import javax.naming.NamingEnumeration;
import javax.naming.NamingException;
import javax.naming.NameAlreadyBoundException;
import javax.naming.NameNotFoundException;
import javax.naming.NotContextException;
import javax.naming.InitialContext;
import javax.naming.OperationNotSupportedException;
import javax.naming.spi.NamingManager;

/**
 * Catalina JNDI Context implementation.
 *
 * @author Remy Maucherat
 * @version $Revision: 467222 $ $Date: 2006-10-24 05:17:11 +0200 (mar., 24 oct. 2006) $
 */
public class NamingContext implements Context {


    // -------------------------------------------------------------- Constants


    /**
     * Name parser for this context.
     */
    protected static final NameParser nameParser = new NameParserImpl();


    private static org.apache.juli.logging.Log log =
        org.apache.juli.logging.LogFactory.getLog(NamingContext.class);


    // ----------------------------------------------------------- Constructors


    /**
     * Builds a naming context using the given environment.
     */
    public NamingContext(Hashtable env, String name) 
        throws NamingException {
        this.bindings = new HashMap();
        this.env = new Hashtable();
        // FIXME ? Could be put in the environment ?
        this.name = name;
        // Populating the environment hashtable
        if (env != null ) {
            Enumeration envEntries = env.keys();
            while (envEntries.hasMoreElements()) {
                String entryName = (String) envEntries.nextElement();
                addToEnvironment(entryName, env.get(entryName));
            }
        }
    }


    /**
     * Builds a naming context using the given environment.
     */
    public NamingContext(Hashtable env, String name, HashMap bindings) 
        throws NamingException {
        this(env, name);
        this.bindings = bindings;
    }


    // ----------------------------------------------------- Instance Variables


    /**
     * Environment.
     */
    protected Hashtable env;


    /**
     * The string manager for this package.
     */
    protected StringManager sm = StringManager.getManager(Constants.Package);


    /**
     * Bindings in this Context.
     */
    protected HashMap bindings;


    /**
     * Name of the associated Catalina Context.
     */
    protected String name;


    // --------------------------------------------------------- Public Methods


    // -------------------------------------------------------- Context Methods


    /**
     * Retrieves the named object. 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).
     * 
     * @param name the name of the object to look up
     * @return the object bound to name
     * @exception NamingException if a naming exception is encountered
     */
    public Object lookup(Name name)
        throws NamingException {
        return lookup(name, true);
    }


    /**
     * Retrieves the named object.
     * 
     * @param name the name of the object to look up
     * @return the object bound to name
     * @exception NamingException if a naming exception is encountered
     */
    public Object lookup(String name)
        throws NamingException {
        return lookup(new CompositeName(name), true);
    }


    /**
     * 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
     * @exception NameAlreadyBoundException if name is already bound
     * @exception InvalidAttributesException if object did not supply all 
     * mandatory attributes
     * @exception NamingException if a naming exception is encountered
     */
    public void bind(Name name, Object obj)
        throws NamingException {
        bind(name, obj, false);
    }


    /**
     * Binds a name to an object.
     * 
     * @param name the name to bind; may not be empty
     * @param obj the object to bind; possibly null
     * @exception NameAlreadyBoundException if name is already bound
     * @exception InvalidAttributesException if object did not supply all 
     * mandatory attributes
     * @exception NamingException if a naming exception is encountered
     */
    public void bind(String name, Object obj)
        throws NamingException {
        bind(new CompositeName(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>
     * If the object is a DirContext, 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
     * @exception InvalidAttributesException if object did not supply all 
     * mandatory attributes
     * @exception NamingException if a naming exception is encountered
     */
    public void rebind(Name name, Object obj)
        throws NamingException {
        bind(name, obj, true);
    }


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


    /**
     * Unbinds the named object. Removes the terminal atomic name in name 
     * from the target context--that named by all but the terminal atomic 
     * part of name.
     * <p>
     * This method is idempotent. It succeeds even if the terminal atomic 
     * name is not bound in the target context, but throws 
     * NameNotFoundException if any of the intermediate contexts do not exist. 
     * 
     * @param name the name to bind; may not be empty
     * @exception NameNotFoundException if an intermediate context does not 
     * exist
     * @exception NamingException if a naming exception is encountered
     */
    public void unbind(Name name)
        throws NamingException {
        checkWritable();
        
        while ((!name.isEmpty()) && (name.get(0).length() == 0))
            name = name.getSuffix(1);
        if (name.isEmpty())
            throw new NamingException
                (sm.getString("namingContext.invalidName"));
        
        NamingEntry entry = (NamingEntry) bindings.get(name.get(0));
        
        if (entry == null) {
            throw new NameNotFoundException
                (sm.getString("namingContext.nameNotBound", name.get(0)));
        }
        
        if (name.size() > 1) {
            if (entry.type == NamingEntry.CONTEXT) {
                ((Context) entry.value).unbind(name.getSuffix(1));
            } else {
                throw new NamingException
                    (sm.getString("namingContext.contextExpected"));
            }
        } else {
            bindings.remove(name.get(0));
        }
        
    }


    /**
     * Unbinds the named object.
     * 
     * @param name the name to bind; may not be empty
     * @exception NameNotFoundException if an intermediate context does not 
     * exist
     * @exception NamingException if a naming exception is encountered
     */
    public void unbind(String name)
        throws NamingException {
        unbind(new CompositeName(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
     * @exception NameAlreadyBoundException if newName is already bound
     * @exception NamingException if a naming exception is encountered
     */
    public void rename(Name oldName, Name newName)
        throws NamingException {
        Object value = lookup(oldName);
        bind(newName, value);
        unbind(oldName);
    }