content: /*
   * Copyright 2014 The Netty Project
   *
   * The Netty Project 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:
   *
   *   https://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.taobao.arthas.grpcweb.proxy;
  
  import io.netty.buffer.ByteBuf;
  import io.netty.buffer.ByteBufAllocator;
  import io.netty.channel.ChannelHandlerContext;
  import io.netty.handler.codec.http.DefaultHttpContent;
  import io.netty.handler.codec.http.HttpContent;
  import io.netty.handler.codec.http.LastHttpContent;
  import io.netty.handler.stream.ChunkedInput;
  
  /**
   * 和 LastHttpContent 对比，少了 LastHttpContent.EMPTY_LAST_CONTENT
   * 
   * @see LastHttpContent
   * @see LastHttpContent#EMPTY_LAST_CONTENT
   */
  public class SingleHttpChunkedInput implements ChunkedInput<HttpContent> {
  
      private final ChunkedInput<ByteBuf> input;
  
      /**
       * Creates a new instance using the specified input.
       * @param input {@link ChunkedInput} containing data to write
       */
      public SingleHttpChunkedInput(ChunkedInput<ByteBuf> input) {
          this.input = input;
  //        lastHttpContent = LastHttpContent.EMPTY_LAST_CONTENT;
      }
  
      /**
       * Creates a new instance using the specified input. {@code lastHttpContent} will be written as the terminating
       * chunk.
       * @param input {@link ChunkedInput} containing data to write
       * @param lastHttpContent {@link LastHttpContent} that will be written as the terminating chunk. Use this for
       *            training headers.
       */
      public SingleHttpChunkedInput(ChunkedInput<ByteBuf> input, LastHttpContent lastHttpContent) {
          this.input = input;
  //        this.lastHttpContent = lastHttpContent;
      }
  
      @Override
      public boolean isEndOfInput() throws Exception {
          if (input.isEndOfInput()) {
              // Only end of input after last HTTP chunk has been sent
              return true;
          } else {
              return false;
          }
      }
  
      @Override
      public void close() throws Exception {
          input.close();
      }
  
      @Deprecated
      @Override
      public HttpContent readChunk(ChannelHandlerContext ctx) throws Exception {
          return readChunk(ctx.alloc());
      }
  
      @Override
      public HttpContent readChunk(ByteBufAllocator allocator) throws Exception {
          if (input.isEndOfInput()) {
              return null;
          } else {
              ByteBuf buf = input.readChunk(allocator);
              if (buf == null) {
                  return null;
              }
              return new DefaultHttpContent(buf);
          }
      }
  
      @Override
      public long length() {
          return input.length();
      }
  
      @Override
      public long progress() {
          return input.progress();
      }
  }
  