| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You 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 org.apache.coyote.http2; |
| |
| import java.util.Collections; |
| import java.util.Set; |
| import java.util.concurrent.ConcurrentHashMap; |
| |
| import org.apache.juli.logging.Log; |
| import org.apache.juli.logging.LogFactory; |
| import org.apache.tomcat.util.res.StringManager; |
| |
| /** |
| * Used to managed prioritisation. |
| */ |
| abstract class AbstractStream { |
| |
| private static final Log log = LogFactory.getLog(AbstractStream.class); |
| private static final StringManager sm = StringManager.getManager(AbstractStream.class); |
| |
| private final Integer identifier; |
| private final String idAsString; |
| |
| private volatile AbstractStream parentStream = null; |
| private final Set<Stream> childStreams = Collections.newSetFromMap(new ConcurrentHashMap<>()); |
| private long windowSize = ConnectionSettingsBase.DEFAULT_INITIAL_WINDOW_SIZE; |
| |
| |
| AbstractStream(Integer identifier) { |
| this.identifier = identifier; |
| this.idAsString = identifier.toString(); |
| } |
| |
| |
| final Integer getIdentifier() { |
| return identifier; |
| } |
| |
| |
| final String getIdAsString() { |
| return idAsString; |
| } |
| |
| |
| final int getIdAsInt() { |
| return identifier.intValue(); |
| } |
| |
| |
| final void detachFromParent() { |
| if (parentStream != null) { |
| parentStream.getChildStreams().remove(this); |
| parentStream = null; |
| } |
| } |
| |
| |
| final void addChild(Stream child) { |
| child.setParentStream(this); |
| childStreams.add(child); |
| } |
| |
| |
| final boolean isDescendant(AbstractStream stream) { |
| // Is the passed in Stream a descendant of this Stream? |
| // Start at the passed in Stream and work up |
| AbstractStream parent = stream.getParentStream(); |
| while (parent != null && parent != this) { |
| parent = parent.getParentStream(); |
| } |
| return parent != null; |
| } |
| |
| |
| final AbstractStream getParentStream() { |
| return parentStream; |
| } |
| |
| |
| final void setParentStream(AbstractStream parentStream) { |
| this.parentStream = parentStream; |
| } |
| |
| |
| final Set<Stream> getChildStreams() { |
| return childStreams; |
| } |
| |
| |
| final synchronized void setWindowSize(long windowSize) { |
| this.windowSize = windowSize; |
| } |
| |
| |
| final synchronized long getWindowSize() { |
| return windowSize; |
| } |
| |
| |
| /** |
| * Increment window size. |
| * @param increment The amount by which the window size should be increased |
| * @throws Http2Exception If the window size is now higher than |
| * the maximum allowed |
| */ |
| synchronized void incrementWindowSize(int increment) throws Http2Exception { |
| // No need for overflow protection here. |
| // Increment can't be more than Integer.MAX_VALUE and once windowSize |
| // goes beyond 2^31-1 an error is triggered. |
| windowSize += increment; |
| |
| if (log.isDebugEnabled()) { |
| log.debug(sm.getString("abstractStream.windowSizeInc", getConnectionId(), |
| getIdAsString(), Integer.toString(increment), Long.toString(windowSize))); |
| } |
| |
| if (windowSize > ConnectionSettingsBase.MAX_WINDOW_SIZE) { |
| String msg = sm.getString("abstractStream.windowSizeTooBig", getConnectionId(), identifier, |
| Integer.toString(increment), Long.toString(windowSize)); |
| if (identifier.intValue() == 0) { |
| throw new ConnectionException(msg, Http2Error.FLOW_CONTROL_ERROR); |
| } else { |
| throw new StreamException( |
| msg, Http2Error.FLOW_CONTROL_ERROR, identifier.intValue()); |
| } |
| } |
| } |
| |
| |
| final synchronized void decrementWindowSize(int decrement) { |
| // No need for overflow protection here. Decrement can never be larger |
| // the Integer.MAX_VALUE and once windowSize goes negative no further |
| // decrements are permitted |
| windowSize -= decrement; |
| if (log.isDebugEnabled()) { |
| log.debug(sm.getString("abstractStream.windowSizeDec", getConnectionId(), |
| getIdAsString(), Integer.toString(decrement), Long.toString(windowSize))); |
| } |
| } |
| |
| |
| abstract String getConnectionId(); |
| |
| abstract int getWeight(); |
| } |