jdk/src/java.httpclient/share/classes/java/net/http/HeaderFilter.java

/*
 * Copyright (c) 2015, 2016, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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package java.net.http;

import java.io.IOException;

/**
 * A header filter that can examine or modify, typically system headers for
 * requests before they are sent, and responses before they are returned to the
 * user. Some ability to resend requests is provided.
 *
 */
interface HeaderFilter {

    void request(HttpRequestImpl r) throws IOException;

    /**
     * Returns null if response ok to be given to user.  Non null is a request
     * that must be resent and its response given to user. If impl throws an
     * exception that is returned to user instead.
     */
    HttpRequestImpl response(HttpResponseImpl r) throws IOException;
}