1 /*
2 * Copyright 2012 The Netty Project
3 *
4 * The Netty Project licenses this file to you under the Apache License,
5 * version 2.0 (the "License"); you may not use this file except in compliance
6 * with the License. You may obtain a copy of the License at:
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
12 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
13 * License for the specific language governing permissions and limitations
14 * under the License.
15 */
16 package io.netty.handler.codec.compression;
17
18 import io.netty.buffer.ByteBuf;
19 import io.netty.channel.ChannelFuture;
20 import io.netty.channel.ChannelPromise;
21 import io.netty.handler.codec.MessageToByteEncoder;
22
23 /**
24 * Compresses a {@link ByteBuf} using the deflate algorithm.
25 */
26 public abstract class ZlibEncoder extends MessageToByteEncoder<ByteBuf> {
27
28 protected ZlibEncoder() {
29 super(false);
30 }
31
32 /**
33 * Returns {@code true} if and only if the end of the compressed stream
34 * has been reached.
35 */
36 public abstract boolean isClosed();
37
38 /**
39 * Close this {@link ZlibEncoder} and so finish the encoding.
40 *
41 * The returned {@link ChannelFuture} will be notified once the
42 * operation completes.
43 */
44 public abstract ChannelFuture close();
45
46 /**
47 * Close this {@link ZlibEncoder} and so finish the encoding.
48 * The given {@link ChannelFuture} will be notified once the operation
49 * completes and will also be returned.
50 */
51 public abstract ChannelFuture close(ChannelPromise promise);
52
53 }