/*
* Copyright (c) 2001-2004 Caucho Technology, Inc. All rights reserved.
*
* The Apache Software License, Version 1.1
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. The end-user documentation included with the redistribution, if
* any, must include the following acknowlegement:
* "This product includes software developed by the
* Caucho Technology (http://www.caucho.com/)."
* Alternately, this acknowlegement may appear in the software itself,
* if and wherever such third-party acknowlegements normally appear.
*
* 4. The names "Burlap", "Hessian", "Resin", and "Caucho" must not be
* used to endorse or promote products derived from this software
* without prior written permission. For written permission, please contact
* info@caucho.com.
*
* 5. Products derived from this software may not be called "Resin"
* nor may "Resin" appear in their names without prior written
* permission of Caucho Technology.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL CAUCHO TECHNOLOGY OR ITS CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
* OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
* OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
* BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
* OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
* IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* @author Scott Ferguson
*/
package com.caucho.services.name;
/**
* A read-only name service. The name service provides hierarchical
* object lookup. The path names are separated by '/'.
*
* <p>Because the name service is hierarchical, a lookup of an intermediate
* node will return a NameServer instance.
*
* <p>The following example is a simple use of the NameServer:
* <pre>
* /dir-1/1 - where foo contains the string "foo-1"
* /dir-1/2 - where foo contains the string "foo-2"
* /dir-2/1 - where foo contains the string "foo-1"
* /dir-2/2 - where foo contains the string "foo-2"
* </pre>
*
* <p/>The root server might have a URL like:
* <pre>
* http://www.caucho.com/hessian/hessian/name?ejbid=/
* </pre>
*
* <p/>So <code>root.lookup("/dir-1/1")</code> will return the string
* "foo-1", and <code>root.lookup("/dir-1")</code> will return the
* NameServer with the URL:
* <pre>
* http://www.caucho.com/hessian/hessian/name?ejbid=/dir-1
* </pre>
*/
public interface NameServer {
/**
* Lookup an object from the name server.
*
* @param name the relative path name
*
* @return the matching object or null if no object maches
*
* @exception NameServiceException if there's an error
*/
public Object lookup(String name)
throws NameServiceException;
/**
* Lists all the object name components directly below the current context.
* The names are the relative compent name.
*
* <p>For example, if the name server context is "/dir-1", the returned
* values will be ["1", "2"].
*/
public String []list()
throws NameServiceException;
}