http://netty.io/netty-all/: Netty is an asynchronous event-driven network application framework for rapid development of maintainable high performance protocol servers and clients. (The Netty Project) 
public class io.netty.resolver.dns.DnsAddressResolverGroup extends io.netty.resolver.AddressResolverGroup<java.net.InetSocketAddress>
  minor version: 0
  major version: 59
  flags: flags: (0x0021) ACC_PUBLIC, ACC_SUPER
  this_class: io.netty.resolver.dns.DnsAddressResolverGroup
  super_class: io.netty.resolver.AddressResolverGroup
{
  private final io.netty.resolver.dns.DnsNameResolverBuilder dnsResolverBuilder;
    descriptor: Lio/netty/resolver/dns/DnsNameResolverBuilder;
    flags: (0x0012) ACC_PRIVATE, ACC_FINAL

  private final java.util.concurrent.ConcurrentMap<java.lang.String, io.netty.util.concurrent.Promise<java.net.InetAddress>> resolvesInProgress;
    descriptor: Ljava/util/concurrent/ConcurrentMap;
    flags: (0x0012) ACC_PRIVATE, ACC_FINAL
    Signature: Ljava/util/concurrent/ConcurrentMap<Ljava/lang/String;Lio/netty/util/concurrent/Promise<Ljava/net/InetAddress;>;>;

  private final java.util.concurrent.ConcurrentMap<java.lang.String, io.netty.util.concurrent.Promise<java.util.List<java.net.InetAddress>>> resolveAllsInProgress;
    descriptor: Ljava/util/concurrent/ConcurrentMap;
    flags: (0x0012) ACC_PRIVATE, ACC_FINAL
    Signature: Ljava/util/concurrent/ConcurrentMap<Ljava/lang/String;Lio/netty/util/concurrent/Promise<Ljava/util/List<Ljava/net/InetAddress;>;>;>;

  public void <init>(io.netty.resolver.dns.DnsNameResolverBuilder);
    descriptor: (Lio/netty/resolver/dns/DnsNameResolverBuilder;)V
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=2, locals=2, args_size=2
        start local 0 // io.netty.resolver.dns.DnsAddressResolverGroup this
        start local 1 // io.netty.resolver.dns.DnsNameResolverBuilder dnsResolverBuilder
         0: .line 50
            aload 0 /* this */
            invokespecial io.netty.resolver.AddressResolverGroup.<init>:()V
         1: .line 47
            aload 0 /* this */
            invokestatic io.netty.util.internal.PlatformDependent.newConcurrentHashMap:()Ljava/util/concurrent/ConcurrentMap;
            putfield io.netty.resolver.dns.DnsAddressResolverGroup.resolvesInProgress:Ljava/util/concurrent/ConcurrentMap;
         2: .line 48
            aload 0 /* this */
            invokestatic io.netty.util.internal.PlatformDependent.newConcurrentHashMap:()Ljava/util/concurrent/ConcurrentMap;
            putfield io.netty.resolver.dns.DnsAddressResolverGroup.resolveAllsInProgress:Ljava/util/concurrent/ConcurrentMap;
         3: .line 51
            aload 0 /* this */
            aload 1 /* dnsResolverBuilder */
            invokevirtual io.netty.resolver.dns.DnsNameResolverBuilder.copy:()Lio/netty/resolver/dns/DnsNameResolverBuilder;
            putfield io.netty.resolver.dns.DnsAddressResolverGroup.dnsResolverBuilder:Lio/netty/resolver/dns/DnsNameResolverBuilder;
         4: .line 52
            return
        end local 1 // io.netty.resolver.dns.DnsNameResolverBuilder dnsResolverBuilder
        end local 0 // io.netty.resolver.dns.DnsAddressResolverGroup this
      LocalVariableTable:
        Start  End  Slot                Name  Signature
            0    5     0                this  Lio/netty/resolver/dns/DnsAddressResolverGroup;
            0    5     1  dnsResolverBuilder  Lio/netty/resolver/dns/DnsNameResolverBuilder;
    MethodParameters:
                    Name  Flags
      dnsResolverBuilder  

  public void <init>(java.lang.Class<? extends io.netty.channel.socket.DatagramChannel>, io.netty.resolver.dns.DnsServerAddressStreamProvider);
    descriptor: (Ljava/lang/Class;Lio/netty/resolver/dns/DnsServerAddressStreamProvider;)V
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=3, locals=3, args_size=3
        start local 0 // io.netty.resolver.dns.DnsAddressResolverGroup this
        start local 1 // java.lang.Class channelType
        start local 2 // io.netty.resolver.dns.DnsServerAddressStreamProvider nameServerProvider
         0: .line 57
            aload 0 /* this */
            new io.netty.resolver.dns.DnsNameResolverBuilder
            dup
            invokespecial io.netty.resolver.dns.DnsNameResolverBuilder.<init>:()V
            invokespecial io.netty.resolver.dns.DnsAddressResolverGroup.<init>:(Lio/netty/resolver/dns/DnsNameResolverBuilder;)V
         1: .line 58
            aload 0 /* this */
            getfield io.netty.resolver.dns.DnsAddressResolverGroup.dnsResolverBuilder:Lio/netty/resolver/dns/DnsNameResolverBuilder;
            aload 1 /* channelType */
            invokevirtual io.netty.resolver.dns.DnsNameResolverBuilder.channelType:(Ljava/lang/Class;)Lio/netty/resolver/dns/DnsNameResolverBuilder;
            aload 2 /* nameServerProvider */
            invokevirtual io.netty.resolver.dns.DnsNameResolverBuilder.nameServerProvider:(Lio/netty/resolver/dns/DnsServerAddressStreamProvider;)Lio/netty/resolver/dns/DnsNameResolverBuilder;
            pop
         2: .line 59
            return
        end local 2 // io.netty.resolver.dns.DnsServerAddressStreamProvider nameServerProvider
        end local 1 // java.lang.Class channelType
        end local 0 // io.netty.resolver.dns.DnsAddressResolverGroup this
      LocalVariableTable:
        Start  End  Slot                Name  Signature
            0    3     0                this  Lio/netty/resolver/dns/DnsAddressResolverGroup;
            0    3     1         channelType  Ljava/lang/Class<+Lio/netty/channel/socket/DatagramChannel;>;
            0    3     2  nameServerProvider  Lio/netty/resolver/dns/DnsServerAddressStreamProvider;
    Signature: (Ljava/lang/Class<+Lio/netty/channel/socket/DatagramChannel;>;Lio/netty/resolver/dns/DnsServerAddressStreamProvider;)V
    MethodParameters:
                    Name  Flags
      channelType         
      nameServerProvider  

  public void <init>(io.netty.channel.ChannelFactory<? extends io.netty.channel.socket.DatagramChannel>, io.netty.resolver.dns.DnsServerAddressStreamProvider);
    descriptor: (Lio/netty/channel/ChannelFactory;Lio/netty/resolver/dns/DnsServerAddressStreamProvider;)V
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=3, locals=3, args_size=3
        start local 0 // io.netty.resolver.dns.DnsAddressResolverGroup this
        start local 1 // io.netty.channel.ChannelFactory channelFactory
        start local 2 // io.netty.resolver.dns.DnsServerAddressStreamProvider nameServerProvider
         0: .line 64
            aload 0 /* this */
            new io.netty.resolver.dns.DnsNameResolverBuilder
            dup
            invokespecial io.netty.resolver.dns.DnsNameResolverBuilder.<init>:()V
            invokespecial io.netty.resolver.dns.DnsAddressResolverGroup.<init>:(Lio/netty/resolver/dns/DnsNameResolverBuilder;)V
         1: .line 65
            aload 0 /* this */
            getfield io.netty.resolver.dns.DnsAddressResolverGroup.dnsResolverBuilder:Lio/netty/resolver/dns/DnsNameResolverBuilder;
            aload 1 /* channelFactory */
            invokevirtual io.netty.resolver.dns.DnsNameResolverBuilder.channelFactory:(Lio/netty/channel/ChannelFactory;)Lio/netty/resolver/dns/DnsNameResolverBuilder;
            aload 2 /* nameServerProvider */
            invokevirtual io.netty.resolver.dns.DnsNameResolverBuilder.nameServerProvider:(Lio/netty/resolver/dns/DnsServerAddressStreamProvider;)Lio/netty/resolver/dns/DnsNameResolverBuilder;
            pop
         2: .line 66
            return
        end local 2 // io.netty.resolver.dns.DnsServerAddressStreamProvider nameServerProvider
        end local 1 // io.netty.channel.ChannelFactory channelFactory
        end local 0 // io.netty.resolver.dns.DnsAddressResolverGroup this
      LocalVariableTable:
        Start  End  Slot                Name  Signature
            0    3     0                this  Lio/netty/resolver/dns/DnsAddressResolverGroup;
            0    3     1      channelFactory  Lio/netty/channel/ChannelFactory<+Lio/netty/channel/socket/DatagramChannel;>;
            0    3     2  nameServerProvider  Lio/netty/resolver/dns/DnsServerAddressStreamProvider;
    Signature: (Lio/netty/channel/ChannelFactory<+Lio/netty/channel/socket/DatagramChannel;>;Lio/netty/resolver/dns/DnsServerAddressStreamProvider;)V
    MethodParameters:
                    Name  Flags
      channelFactory      
      nameServerProvider  

  protected final io.netty.resolver.AddressResolver<java.net.InetSocketAddress> newResolver(io.netty.util.concurrent.EventExecutor);
    descriptor: (Lio/netty/util/concurrent/EventExecutor;)Lio/netty/resolver/AddressResolver;
    flags: (0x0014) ACC_PROTECTED, ACC_FINAL
    Code:
      stack=5, locals=2, args_size=2
        start local 0 // io.netty.resolver.dns.DnsAddressResolverGroup this
        start local 1 // io.netty.util.concurrent.EventExecutor executor
         0: .line 71
            aload 1 /* executor */
            instanceof io.netty.channel.EventLoop
            ifne 6
         1: .line 72
            new java.lang.IllegalStateException
            dup
         2: .line 73
            new java.lang.StringBuilder
            dup
            ldc "unsupported executor type: "
            invokespecial java.lang.StringBuilder.<init>:(Ljava/lang/String;)V
            aload 1 /* executor */
            invokestatic io.netty.util.internal.StringUtil.simpleClassName:(Ljava/lang/Object;)Ljava/lang/String;
            invokevirtual java.lang.StringBuilder.append:(Ljava/lang/String;)Ljava/lang/StringBuilder;
         3: .line 74
            ldc " (expected: "
            invokevirtual java.lang.StringBuilder.append:(Ljava/lang/String;)Ljava/lang/StringBuilder;
            ldc Lio/netty/channel/EventLoop;
            invokestatic io.netty.util.internal.StringUtil.simpleClassName:(Ljava/lang/Class;)Ljava/lang/String;
            invokevirtual java.lang.StringBuilder.append:(Ljava/lang/String;)Ljava/lang/StringBuilder;
         4: .line 73
            invokevirtual java.lang.StringBuilder.toString:()Ljava/lang/String;
         5: .line 72
            invokespecial java.lang.IllegalStateException.<init>:(Ljava/lang/String;)V
            athrow
         6: .line 79
      StackMap locals:
      StackMap stack:
            aload 0 /* this */
            aload 1 /* executor */
            checkcast io.netty.channel.EventLoop
         7: .line 80
            aload 0 /* this */
            getfield io.netty.resolver.dns.DnsAddressResolverGroup.dnsResolverBuilder:Lio/netty/resolver/dns/DnsNameResolverBuilder;
            invokevirtual io.netty.resolver.dns.DnsNameResolverBuilder.channelFactory:()Lio/netty/channel/ChannelFactory;
         8: .line 81
            aload 0 /* this */
            getfield io.netty.resolver.dns.DnsAddressResolverGroup.dnsResolverBuilder:Lio/netty/resolver/dns/DnsNameResolverBuilder;
            invokevirtual io.netty.resolver.dns.DnsNameResolverBuilder.nameServerProvider:()Lio/netty/resolver/dns/DnsServerAddressStreamProvider;
         9: .line 79
            invokevirtual io.netty.resolver.dns.DnsAddressResolverGroup.newResolver:(Lio/netty/channel/EventLoop;Lio/netty/channel/ChannelFactory;Lio/netty/resolver/dns/DnsServerAddressStreamProvider;)Lio/netty/resolver/AddressResolver;
            areturn
        end local 1 // io.netty.util.concurrent.EventExecutor executor
        end local 0 // io.netty.resolver.dns.DnsAddressResolverGroup this
      LocalVariableTable:
        Start  End  Slot      Name  Signature
            0   10     0      this  Lio/netty/resolver/dns/DnsAddressResolverGroup;
            0   10     1  executor  Lio/netty/util/concurrent/EventExecutor;
    Exceptions:
      throws java.lang.Exception
    Signature: (Lio/netty/util/concurrent/EventExecutor;)Lio/netty/resolver/AddressResolver<Ljava/net/InetSocketAddress;>;
    MethodParameters:
          Name  Flags
      executor  

  protected io.netty.resolver.AddressResolver<java.net.InetSocketAddress> newResolver(io.netty.channel.EventLoop, io.netty.channel.ChannelFactory<? extends io.netty.channel.socket.DatagramChannel>, io.netty.resolver.dns.DnsServerAddressStreamProvider);
    descriptor: (Lio/netty/channel/EventLoop;Lio/netty/channel/ChannelFactory;Lio/netty/resolver/dns/DnsServerAddressStreamProvider;)Lio/netty/resolver/AddressResolver;
    flags: (0x0004) ACC_PROTECTED
    Code:
      stack=7, locals=5, args_size=4
        start local 0 // io.netty.resolver.dns.DnsAddressResolverGroup this
        start local 1 // io.netty.channel.EventLoop eventLoop
        start local 2 // io.netty.channel.ChannelFactory channelFactory
        start local 3 // io.netty.resolver.dns.DnsServerAddressStreamProvider nameServerProvider
         0: .line 92
            new io.netty.resolver.dns.InflightNameResolver
            dup
         1: .line 93
            aload 1 /* eventLoop */
         2: .line 94
            aload 0 /* this */
            aload 1 /* eventLoop */
            aload 2 /* channelFactory */
            aload 3 /* nameServerProvider */
            invokevirtual io.netty.resolver.dns.DnsAddressResolverGroup.newNameResolver:(Lio/netty/channel/EventLoop;Lio/netty/channel/ChannelFactory;Lio/netty/resolver/dns/DnsServerAddressStreamProvider;)Lio/netty/resolver/NameResolver;
         3: .line 95
            aload 0 /* this */
            getfield io.netty.resolver.dns.DnsAddressResolverGroup.resolvesInProgress:Ljava/util/concurrent/ConcurrentMap;
         4: .line 96
            aload 0 /* this */
            getfield io.netty.resolver.dns.DnsAddressResolverGroup.resolveAllsInProgress:Ljava/util/concurrent/ConcurrentMap;
         5: .line 92
            invokespecial io.netty.resolver.dns.InflightNameResolver.<init>:(Lio/netty/util/concurrent/EventExecutor;Lio/netty/resolver/NameResolver;Ljava/util/concurrent/ConcurrentMap;Ljava/util/concurrent/ConcurrentMap;)V
            astore 4 /* resolver */
        start local 4 // io.netty.resolver.NameResolver resolver
         6: .line 98
            aload 0 /* this */
            aload 1 /* eventLoop */
            aload 4 /* resolver */
            invokevirtual io.netty.resolver.dns.DnsAddressResolverGroup.newAddressResolver:(Lio/netty/channel/EventLoop;Lio/netty/resolver/NameResolver;)Lio/netty/resolver/AddressResolver;
            areturn
        end local 4 // io.netty.resolver.NameResolver resolver
        end local 3 // io.netty.resolver.dns.DnsServerAddressStreamProvider nameServerProvider
        end local 2 // io.netty.channel.ChannelFactory channelFactory
        end local 1 // io.netty.channel.EventLoop eventLoop
        end local 0 // io.netty.resolver.dns.DnsAddressResolverGroup this
      LocalVariableTable:
        Start  End  Slot                Name  Signature
            0    7     0                this  Lio/netty/resolver/dns/DnsAddressResolverGroup;
            0    7     1           eventLoop  Lio/netty/channel/EventLoop;
            0    7     2      channelFactory  Lio/netty/channel/ChannelFactory<+Lio/netty/channel/socket/DatagramChannel;>;
            0    7     3  nameServerProvider  Lio/netty/resolver/dns/DnsServerAddressStreamProvider;
            6    7     4            resolver  Lio/netty/resolver/NameResolver<Ljava/net/InetAddress;>;
    Exceptions:
      throws java.lang.Exception
    Signature: (Lio/netty/channel/EventLoop;Lio/netty/channel/ChannelFactory<+Lio/netty/channel/socket/DatagramChannel;>;Lio/netty/resolver/dns/DnsServerAddressStreamProvider;)Lio/netty/resolver/AddressResolver<Ljava/net/InetSocketAddress;>;
    RuntimeVisibleAnnotations: 
      java.lang.Deprecated()
    MethodParameters:
                    Name  Flags
      eventLoop           
      channelFactory      
      nameServerProvider  

  protected io.netty.resolver.NameResolver<java.net.InetAddress> newNameResolver(io.netty.channel.EventLoop, io.netty.channel.ChannelFactory<? extends io.netty.channel.socket.DatagramChannel>, io.netty.resolver.dns.DnsServerAddressStreamProvider);
    descriptor: (Lio/netty/channel/EventLoop;Lio/netty/channel/ChannelFactory;Lio/netty/resolver/dns/DnsServerAddressStreamProvider;)Lio/netty/resolver/NameResolver;
    flags: (0x0004) ACC_PROTECTED
    Code:
      stack=2, locals=4, args_size=4
        start local 0 // io.netty.resolver.dns.DnsAddressResolverGroup this
        start local 1 // io.netty.channel.EventLoop eventLoop
        start local 2 // io.netty.channel.ChannelFactory channelFactory
        start local 3 // io.netty.resolver.dns.DnsServerAddressStreamProvider nameServerProvider
         0: .line 111
            aload 0 /* this */
            getfield io.netty.resolver.dns.DnsAddressResolverGroup.dnsResolverBuilder:Lio/netty/resolver/dns/DnsNameResolverBuilder;
            aload 1 /* eventLoop */
            invokevirtual io.netty.resolver.dns.DnsNameResolverBuilder.eventLoop:(Lio/netty/channel/EventLoop;)Lio/netty/resolver/dns/DnsNameResolverBuilder;
         1: .line 112
            aload 2 /* channelFactory */
            invokevirtual io.netty.resolver.dns.DnsNameResolverBuilder.channelFactory:(Lio/netty/channel/ChannelFactory;)Lio/netty/resolver/dns/DnsNameResolverBuilder;
         2: .line 113
            aload 3 /* nameServerProvider */
            invokevirtual io.netty.resolver.dns.DnsNameResolverBuilder.nameServerProvider:(Lio/netty/resolver/dns/DnsServerAddressStreamProvider;)Lio/netty/resolver/dns/DnsNameResolverBuilder;
         3: .line 114
            invokevirtual io.netty.resolver.dns.DnsNameResolverBuilder.build:()Lio/netty/resolver/dns/DnsNameResolver;
         4: .line 111
            areturn
        end local 3 // io.netty.resolver.dns.DnsServerAddressStreamProvider nameServerProvider
        end local 2 // io.netty.channel.ChannelFactory channelFactory
        end local 1 // io.netty.channel.EventLoop eventLoop
        end local 0 // io.netty.resolver.dns.DnsAddressResolverGroup this
      LocalVariableTable:
        Start  End  Slot                Name  Signature
            0    5     0                this  Lio/netty/resolver/dns/DnsAddressResolverGroup;
            0    5     1           eventLoop  Lio/netty/channel/EventLoop;
            0    5     2      channelFactory  Lio/netty/channel/ChannelFactory<+Lio/netty/channel/socket/DatagramChannel;>;
            0    5     3  nameServerProvider  Lio/netty/resolver/dns/DnsServerAddressStreamProvider;
    Exceptions:
      throws java.lang.Exception
    Signature: (Lio/netty/channel/EventLoop;Lio/netty/channel/ChannelFactory<+Lio/netty/channel/socket/DatagramChannel;>;Lio/netty/resolver/dns/DnsServerAddressStreamProvider;)Lio/netty/resolver/NameResolver<Ljava/net/InetAddress;>;
    MethodParameters:
                    Name  Flags
      eventLoop           
      channelFactory      
      nameServerProvider  

  protected io.netty.resolver.AddressResolver<java.net.InetSocketAddress> newAddressResolver(io.netty.channel.EventLoop, io.netty.resolver.NameResolver<java.net.InetAddress>);
    descriptor: (Lio/netty/channel/EventLoop;Lio/netty/resolver/NameResolver;)Lio/netty/resolver/AddressResolver;
    flags: (0x0004) ACC_PROTECTED
    Code:
      stack=4, locals=3, args_size=3
        start local 0 // io.netty.resolver.dns.DnsAddressResolverGroup this
        start local 1 // io.netty.channel.EventLoop eventLoop
        start local 2 // io.netty.resolver.NameResolver resolver
         0: .line 124
            new io.netty.resolver.InetSocketAddressResolver
            dup
            aload 1 /* eventLoop */
            aload 2 /* resolver */
            invokespecial io.netty.resolver.InetSocketAddressResolver.<init>:(Lio/netty/util/concurrent/EventExecutor;Lio/netty/resolver/NameResolver;)V
            areturn
        end local 2 // io.netty.resolver.NameResolver resolver
        end local 1 // io.netty.channel.EventLoop eventLoop
        end local 0 // io.netty.resolver.dns.DnsAddressResolverGroup this
      LocalVariableTable:
        Start  End  Slot       Name  Signature
            0    1     0       this  Lio/netty/resolver/dns/DnsAddressResolverGroup;
            0    1     1  eventLoop  Lio/netty/channel/EventLoop;
            0    1     2   resolver  Lio/netty/resolver/NameResolver<Ljava/net/InetAddress;>;
    Exceptions:
      throws java.lang.Exception
    Signature: (Lio/netty/channel/EventLoop;Lio/netty/resolver/NameResolver<Ljava/net/InetAddress;>;)Lio/netty/resolver/AddressResolver<Ljava/net/InetSocketAddress;>;
    MethodParameters:
           Name  Flags
      eventLoop  
      resolver   
}
Signature: Lio/netty/resolver/AddressResolverGroup<Ljava/net/InetSocketAddress;>;
SourceFile: "DnsAddressResolverGroup.java"