Java Servlet API 4.0.1 Source Code Files are important if you want to compile them with different JDK releases.

You can get Java Servlet API 4.0.1 Source Code Files from Servlet API Maven Website in the "4.0.1/" folder.

You can also browse Java Servlet API 4.0.1 Source Code files below:

⏎ javax/servlet/FilterConfig.java

/*
 * Copyright (c) 1997-2018 Oracle and/or its affiliates. All rights reserved.
 * Copyright 2004 The Apache Software Foundation
 *
 * 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 javax.servlet;

import java.util.Enumeration;

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

    /** 
     * Returns the filter-name of this filter as defined in the deployment
     * descriptor. 
     *
     * @return the filter name of this filter
     */
    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 initialization 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, or <code>null</code> if 
     * the initialization parameter does not exist
     */
    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();

}

⏎ javax/servlet/FilterConfig.java

Or download all of them as a single archive file:

File name: javax.servlet-api-4.0.1-sources.jar
File size: 203006 bytes
Release date: 2018-04-20
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