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16 package io.netty.handler.codec.http.websocketx;
17
18 import io.netty.buffer.ByteBuf;
19 import io.netty.buffer.Unpooled;
20 import io.netty.channel.ChannelHandler.Sharable;
21 import io.netty.channel.ChannelHandlerContext;
22 import io.netty.handler.codec.MessageToMessageEncoder;
23
24 import java.util.List;
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32 @Sharable
33 public class WebSocket00FrameEncoder extends MessageToMessageEncoder<WebSocketFrame> implements WebSocketFrameEncoder {
34 private static final ByteBuf _0X00 = Unpooled.unreleasableBuffer(
35 Unpooled.directBuffer(1, 1).writeByte(0x00)).asReadOnly();
36 private static final ByteBuf _0XFF = Unpooled.unreleasableBuffer(
37 Unpooled.directBuffer(1, 1).writeByte((byte) 0xFF)).asReadOnly();
38 private static final ByteBuf _0XFF_0X00 = Unpooled.unreleasableBuffer(
39 Unpooled.directBuffer(2, 2).writeByte((byte) 0xFF).writeByte(0x00)).asReadOnly();
40
41 public WebSocket00FrameEncoder() {
42 super(WebSocketFrame.class);
43 }
44
45 @Override
46 protected void encode(ChannelHandlerContext ctx, WebSocketFrame msg, List<Object> out) throws Exception {
47 if (msg instanceof TextWebSocketFrame) {
48
49 ByteBuf data = msg.content();
50
51 out.add(_0X00.duplicate());
52 out.add(data.retain());
53 out.add(_0XFF.duplicate());
54 } else if (msg instanceof CloseWebSocketFrame) {
55
56
57 out.add(_0XFF_0X00.duplicate());
58 } else {
59
60 ByteBuf data = msg.content();
61 int dataLen = data.readableBytes();
62
63 ByteBuf buf = ctx.alloc().buffer(5);
64 boolean release = true;
65 try {
66
67 buf.writeByte((byte) 0x80);
68
69
70 int b1 = dataLen >>> 28 & 0x7F;
71 int b2 = dataLen >>> 14 & 0x7F;
72 int b3 = dataLen >>> 7 & 0x7F;
73 int b4 = dataLen & 0x7F;
74 if (b1 == 0) {
75 if (b2 == 0) {
76 if (b3 != 0) {
77 buf.writeByte(b3 | 0x80);
78 }
79 buf.writeByte(b4);
80 } else {
81 buf.writeByte(b2 | 0x80);
82 buf.writeByte(b3 | 0x80);
83 buf.writeByte(b4);
84 }
85 } else {
86 buf.writeByte(b1 | 0x80);
87 buf.writeByte(b2 | 0x80);
88 buf.writeByte(b3 | 0x80);
89 buf.writeByte(b4);
90 }
91
92
93 out.add(buf);
94 out.add(data.retain());
95 release = false;
96 } finally {
97 if (release) {
98 buf.release();
99 }
100 }
101 }
102 }
103 }