http://www.jboss.org/undertow-parent/undertow-core: Undertow (JBoss by Red Hat) 
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 * Copyright 2014 Red Hat, Inc., and individual contributors
 * as indicated by the @author tags.
 *
 * 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,
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 *  See the License for the specific language governing permissions and
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package io.undertow.server;

import io.undertow.util.ConduitFactory;
import org.xnio.conduits.Conduit;


Interface that provides a means of wrapping a Conduit. Every conduit wrapper has a chance to replace the conduit with a conduit which either wraps or replaces the passed in conduit. However it is the responsibility of either the conduit wrapper instance or the conduit it creates to ensure that the original conduit is eventually cleaned up and shut down properly when the request is terminated. 
Author:Stuart Douglas
/**
 * Interface that provides a means of wrapping a {@link Conduit}.  Every conduit wrapper has a chance
 * to replace the conduit with a conduit which either wraps or replaces the passed in conduit.  However it is the responsibility
 * of either the conduit wrapper instance or the conduit it creates to ensure that the original conduit is eventually
 * cleaned up and shut down properly when the request is terminated.
 *
 * @author Stuart Douglas
 */
public interface ConduitWrapper<T extends Conduit> {

    
Wrap the conduit. The wrapper should not return null. If no wrapping is desired, the original conduit should be returned. 
Params:
  • factory – the original conduit
  • exchange – the in-flight HTTP exchange
Returns:the replacement conduit
/**
     * Wrap the conduit.  The wrapper should not return {@code null}.  If no wrapping is desired, the original
     * conduit should be returned.
     *
     * @param factory the original conduit
     * @param exchange the in-flight HTTP exchange
     * @return the replacement conduit
     */
    T wrap(final ConduitFactory<T> factory, final HttpServerExchange exchange);
}