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16 package io.netty.example.http2.helloworld.frame.server;
17
18 import io.netty.buffer.ByteBuf;
19 import io.netty.buffer.ByteBufUtil;
20 import io.netty.channel.ChannelDuplexHandler;
21 import io.netty.channel.ChannelHandler.Sharable;
22 import io.netty.channel.ChannelHandlerContext;
23 import io.netty.handler.codec.http2.DefaultHttp2DataFrame;
24 import io.netty.handler.codec.http2.DefaultHttp2Headers;
25 import io.netty.handler.codec.http2.DefaultHttp2HeadersFrame;
26 import io.netty.handler.codec.http2.DefaultHttp2WindowUpdateFrame;
27 import io.netty.handler.codec.http2.Http2DataFrame;
28 import io.netty.handler.codec.http2.Http2FrameStream;
29 import io.netty.handler.codec.http2.Http2Headers;
30 import io.netty.handler.codec.http2.Http2HeadersFrame;
31 import io.netty.util.CharsetUtil;
32
33 import static io.netty.buffer.Unpooled.copiedBuffer;
34 import static io.netty.buffer.Unpooled.unreleasableBuffer;
35 import static io.netty.handler.codec.http.HttpResponseStatus.OK;
36
37
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39
40 @Sharable
41 public class HelloWorldHttp2Handler extends ChannelDuplexHandler {
42
43 static final ByteBuf RESPONSE_BYTES = unreleasableBuffer(
44 copiedBuffer("Hello World", CharsetUtil.UTF_8)).asReadOnly();
45
46 @Override
47 public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {
48 super.exceptionCaught(ctx, cause);
49 cause.printStackTrace();
50 ctx.close();
51 }
52
53 @Override
54 public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {
55 if (msg instanceof Http2HeadersFrame) {
56 onHeadersRead(ctx, (Http2HeadersFrame) msg);
57 } else if (msg instanceof Http2DataFrame) {
58 onDataRead(ctx, (Http2DataFrame) msg);
59 } else {
60 super.channelRead(ctx, msg);
61 }
62 }
63
64 @Override
65 public void channelReadComplete(ChannelHandlerContext ctx) throws Exception {
66 ctx.flush();
67 }
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72 private static void onDataRead(ChannelHandlerContext ctx, Http2DataFrame data) throws Exception {
73 Http2FrameStream stream = data.stream();
74
75 if (data.isEndStream()) {
76 sendResponse(ctx, stream, data.content());
77 } else {
78
79 data.release();
80 }
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83 ctx.write(new DefaultHttp2WindowUpdateFrame(data.initialFlowControlledBytes()).stream(stream));
84 }
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89 private static void onHeadersRead(ChannelHandlerContext ctx, Http2HeadersFrame headers)
90 throws Exception {
91 if (headers.isEndStream()) {
92 ByteBuf content = ctx.alloc().buffer();
93 content.writeBytes(RESPONSE_BYTES.duplicate());
94 ByteBufUtil.writeAscii(content, " - via HTTP/2");
95 sendResponse(ctx, headers.stream(), content);
96 }
97 }
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102 private static void sendResponse(ChannelHandlerContext ctx, Http2FrameStream stream, ByteBuf payload) {
103
104 Http2Headers headers = new DefaultHttp2Headers().status(OK.codeAsText());
105 ctx.write(new DefaultHttp2HeadersFrame(headers).stream(stream));
106 ctx.write(new DefaultHttp2DataFrame(payload, true).stream(stream));
107 }
108 }