https://javaee.github.io/servlet-spec/: Java.net - The Source for Java Technology Collaboration (GlassFish Community) 
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 * 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.io.IOException;

    
A FilterChain is an object provided by the servlet container to the developer
giving a view into the invocation chain of a filtered request for a resource. Filters
use the FilterChain to invoke the next filter in the chain, or if the calling filter
is the last filter in the chain, to invoke the resource at the end of the chain.

See Also:
  • Filter
Since:Servlet 2.3
/**
     * A FilterChain is an object provided by the servlet container to the developer
     * giving a view into the invocation chain of a filtered request for a resource. Filters
     * use the FilterChain to invoke the next filter in the chain, or if the calling filter
     * is the last filter in the chain, to invoke the resource at the end of the chain.
     *
     * @see Filter
     * @since Servlet 2.3
     */

public interface FilterChain {

    
Causes the next filter in the chain to be invoked, or if the calling filter is the last filter
in the chain, causes the resource at the end of the chain to be invoked.

Params:
  • request – the request to pass along the chain.
  • response – the response to pass along the chain.
Throws:
  • IOException – if an I/O related error has occurred during the processing
  • ServletException – if an exception has occurred that interferes with the
                         filterChain's normal operation
/**
     * Causes the next filter in the chain to be invoked, or if the calling filter is the last filter
     * in the chain, causes the resource at the end of the chain to be invoked.
     *
     * @param request the request to pass along the chain.
     * @param response the response to pass along the chain.
     * @throws IOException if an I/O related error has occurred during the processing
     * @throws ServletException if an exception has occurred that interferes with the
     *                          filterChain's normal operation
     */
    public void doFilter(ServletRequest request, ServletResponse response) throws IOException, ServletException;

}