http://www.jboss.org/undertow-parent/undertow-core: Undertow (JBoss by Red Hat) 
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 *     http://www.apache.org/licenses/LICENSE-2.0
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package io.undertow.server.protocol.framed;

import java.util.Deque;
import java.util.List;


Interface that can be used to determine where to insert a given frame into the pending frame queue.

Author:Stuart Douglas
/**
 *
 * Interface that can be used to determine where to insert a given frame into the pending frame queue.
 *
 * @author Stuart Douglas
 */
public interface FramePriority<C extends AbstractFramedChannel<C, R, S>, R extends AbstractFramedStreamSourceChannel<C, R, S>, S extends AbstractFramedStreamSinkChannel<C, R, S>> {

    
Inserts the new frame at the correct location in the pending frame list. Note that this must
never insert a frame at the very start of the senders list, as this frame has already been activated.
This method should return true if the frame was successfully inserted into the pending frame list,
if it returns false the frame must not be inserted and will be added to the held frames list instead.
Frames held in the held frames list are frames that are not yet ready to be included in the pending frame
list, generally because other frames have to be written first.
Note that if this method returns true without adding the frame the frame will be dropped.

Params:
  • newFrame – The new frame to insert into the pending frame list
  • pendingFrames – The pending frame list
Returns:true if the frame can be inserted into the pending frame list
/**
     * Inserts the new frame at the correct location in the pending frame list. Note that this must
     * never insert a frame at the very start of the senders list, as this frame has already been activated.
     *
     * This method should return true if the frame was successfully inserted into the pending frame list,
     * if it returns false the frame must not be inserted and will be added to the held frames list instead.
     *
     * Frames held in the held frames list are frames that are not yet ready to be included in the pending frame
     * list, generally because other frames have to be written first.
     *
     * Note that if this method returns true without adding the frame the frame will be dropped.
     *
     * @param newFrame The new frame to insert into the pending frame list
     * @param pendingFrames The pending frame list
     * @return true if the frame can be inserted into the pending frame list
     */
    boolean insertFrame(S newFrame, final List<S> pendingFrames);

    
Invoked when a new frame is successfully added to the pending frames queue.
If frames in the held frame queue are now eligible to be sent they can be added
to the pending frames queue.
Note that if the protocol has explicitly asked for the held frames to be recalculated
then the added frame may be null.

Params:
  • addedFrame – The newly added frame
  • pendingFrames – The pending frame queue
  • holdFrames – The held frame queue
/**
     * Invoked when a new frame is successfully added to the pending frames queue.
     *
     * If frames in the held frame queue are now eligible to be sent they can be added
     * to the pending frames queue.
     *
     * Note that if the protocol has explicitly asked for the held frames to be recalculated
     * then the added frame may be null.
     *
     * @param addedFrame The newly added frame
     * @param pendingFrames The pending frame queue
     * @param holdFrames The held frame queue
     */
    void frameAdded(S addedFrame, final List<S> pendingFrames, final Deque<S> holdFrames);

}