/*
 * Copyright (c) OSGi Alliance (2000, 2008). All Rights Reserved.
 *
 * Licensed 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.osgi.service.http;

/**
 * A NamespaceException is thrown to indicate an error with the caller's request
 * to register a servlet or resources into the URI namespace of the Http
 * Service. This exception indicates that the requested alias already is in use.
 * 
 * @version $Revision: 6083 $
 */
public class NamespaceException extends Exception {
    static final long serialVersionUID = 7235606031147877747L;
    
	/**
	 * Construct a <code>NamespaceException</code> object with a detail message.
	 * 
	 * @param message the detail message
	 */
	public NamespaceException(String message) {
		super(message);
	}

	/**
	 * Construct a <code>NamespaceException</code> object with a detail message
	 * and a nested exception.
	 * 
	 * @param message The detail message.
	 * @param cause The nested exception.
	 */
	public NamespaceException(String message, Throwable cause) {
		super(message, cause);
	}

	/**
	 * Returns the nested exception.
	 * 
	 * <p>
	 * This method predates the general purpose exception chaining mechanism.
	 * The <code>getCause()</code> method is now the preferred means of
	 * obtaining this information.
	 * 
	 * @return The result of calling <code>getCause()</code>.
	 */
	public Throwable getException() {
		return getCause();
	}
	
	/**
	 * Returns the cause of this exception or <code>null</code> if no cause was
	 * set.
	 * 
	 * @return The cause of this exception or <code>null</code> if no cause was
	 *         set.
	 * @since 1.2
	 */
	public Throwable getCause() {
		return super.getCause();
	}

	/**
	 * Initializes the cause of this exception to the specified value.
	 * 
	 * @param cause The cause of this exception.
	 * @return This exception.
	 * @throws IllegalArgumentException If the specified cause is this
	 *         exception.
	 * @throws IllegalStateException If the cause of this exception has already
	 *         been set.
	 * @since 1.2
	 */
	public Throwable initCause(Throwable cause) {
		return super.initCause(cause);
	}
}
