Java tutorial
/* * Copyright 2015 Twitter, Inc. * * 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 com.twitter.http2; import io.netty.buffer.ByteBuf; import io.netty.buffer.Unpooled; import io.netty.util.IllegalReferenceCountException; import io.netty.util.internal.StringUtil; /** * The default {@link HttpDataFrame} implementation. */ public class DefaultHttpDataFrame extends DefaultHttpStreamFrame implements HttpDataFrame { private final ByteBuf data; private boolean last; /** * Creates a new instance. * * @param streamId the stream identifier of this frame */ public DefaultHttpDataFrame(int streamId) { this(streamId, Unpooled.buffer(0)); } /** * Creates a new instance. * * @param streamId the stream identifier of this frame * @param data the payload of the frame. Can not exceed {@link HttpCodecUtil#HTTP_MAX_LENGTH} */ public DefaultHttpDataFrame(int streamId, ByteBuf data) { super(streamId); if (data == null) { throw new NullPointerException("data"); } this.data = validate(data); } private static ByteBuf validate(ByteBuf data) { if (data.readableBytes() > HttpCodecUtil.HTTP_MAX_LENGTH) { throw new IllegalArgumentException( "data payload cannot exceed " + HttpCodecUtil.HTTP_MAX_LENGTH + " bytes"); } return data; } @Override public boolean isLast() { return last; } @Override public HttpDataFrame setLast(boolean last) { this.last = last; return this; } @Override public HttpDataFrame setStreamId(int streamId) { super.setStreamId(streamId); return this; } @Override public ByteBuf content() { if (data.refCnt() <= 0) { throw new IllegalReferenceCountException(data.refCnt()); } return data; } @Override public HttpDataFrame copy() { HttpDataFrame frame = new DefaultHttpDataFrame(getStreamId(), content().copy()); frame.setLast(isLast()); return frame; } @Override public HttpDataFrame duplicate() { HttpDataFrame frame = new DefaultHttpDataFrame(getStreamId(), content().duplicate()); frame.setLast(isLast()); return frame; } @Override public int refCnt() { return data.refCnt(); } @Override public HttpDataFrame retain() { data.retain(); return this; } @Override public HttpDataFrame retain(int increment) { data.retain(increment); return this; } @Override public boolean release() { return data.release(); } @Override public boolean release(int decrement) { return data.release(decrement); } @Override public String toString() { StringBuilder buf = new StringBuilder(); buf.append(StringUtil.simpleClassName(this)); buf.append("(last: "); buf.append(isLast()); buf.append(')'); buf.append(StringUtil.NEWLINE); buf.append("--> Stream-ID = "); buf.append(getStreamId()); buf.append(StringUtil.NEWLINE); buf.append("--> Size = "); if (refCnt() == 0) { buf.append("(freed)"); } else { buf.append(content().readableBytes()); } return buf.toString(); } }