/*
 * 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 javax.servlet;

import java.util.Enumeration;

/**
 * A filter configuration object used by a servlet container
 * to pass information to a filter during initialization.
 *
 * @since Servlet 2.3
 * @see Filter
 */


public interface FilterConfig {

    /**
     * Returns the filter-name of this filter as defined in the deployment descriptor.
     * @return the filter name as specified in the deployment descriptor
     */
    public String getFilterName();

    /**
     * Returns a reference to the {@link ServletContext} in which the caller
     * is executing.
     *
     * @return a {@link ServletContext} object, used
     * by the caller to interact with its servlet
     * container
     * @see                ServletContext
     */
    public ServletContext getServletContext();

    /**
     * Returns a <code>String</code> containing the value of the
     * named initialization parameter, or <code>null</code> if
     * the parameter does not exist.
     *
     * @param name a <code>String</code> specifying the name
     *             of the initialization parameter
     * @return a <code>String</code> containing the value
     * of the initialization parameter
     */
    public String getInitParameter(String name);


    /**
     * Returns the names of the filter's initialization parameters
     * as an <code>Enumeration</code> of <code>String</code> objects,
     * or an empty <code>Enumeration</code> if the filter has
     * no initialization parameters.
     *
     * @return an <code>Enumeration</code> of <code>String</code>
     * objects containing the names of the filter's
     * initialization parameters
     */
    public Enumeration<String> getInitParameterNames();


}