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16 package io.netty.handler.codec.dns;
17
18 import io.netty.buffer.ByteBuf;
19 import io.netty.channel.AddressedEnvelope;
20 import io.netty.channel.ChannelHandler;
21 import io.netty.channel.ChannelHandlerContext;
22 import io.netty.channel.socket.DatagramPacket;
23 import io.netty.handler.codec.MessageToMessageEncoder;
24 import io.netty.util.internal.UnstableApi;
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26 import java.net.InetSocketAddress;
27 import java.util.List;
28
29 import static io.netty.util.internal.ObjectUtil.checkNotNull;
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35 @UnstableApi
36 @ChannelHandler.Sharable
37 public class DatagramDnsResponseEncoder
38 extends MessageToMessageEncoder<AddressedEnvelope<DnsResponse, InetSocketAddress>> {
39
40 private final DnsRecordEncoder recordEncoder;
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45 public DatagramDnsResponseEncoder() {
46 this(DnsRecordEncoder.DEFAULT);
47 }
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52 public DatagramDnsResponseEncoder(DnsRecordEncoder recordEncoder) {
53 this.recordEncoder = checkNotNull(recordEncoder, "recordEncoder");
54 }
55
56 @Override
57 protected void encode(ChannelHandlerContext ctx,
58 AddressedEnvelope<DnsResponse, InetSocketAddress> in, List<Object> out) throws Exception {
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60 final InetSocketAddress recipient = in.recipient();
61 final DnsResponse response = in.content();
62 final ByteBuf buf = allocateBuffer(ctx, in);
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64 DnsMessageUtil.encodeDnsResponse(recordEncoder, response, buf);
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66 out.add(new DatagramPacket(buf, recipient, null));
67 }
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73 protected ByteBuf allocateBuffer(
74 ChannelHandlerContext ctx,
75 @SuppressWarnings("unused") AddressedEnvelope<DnsResponse, InetSocketAddress> msg) throws Exception {
76 return ctx.alloc().ioBuffer(1024);
77 }
78 }