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 abstract class io.netty.bootstrap.AbstractBootstrapConfig<B extends io.netty.bootstrap.AbstractBootstrap<B, C>, C extends io.netty.channel.Channel>
  minor version: 0
  major version: 59
  flags: flags: (0x0421) ACC_PUBLIC, ACC_SUPER, ACC_ABSTRACT
  this_class: io.netty.bootstrap.AbstractBootstrapConfig
  super_class: java.lang.Object
{
  protected final B bootstrap;
    descriptor: Lio/netty/bootstrap/AbstractBootstrap;
    flags: (0x0014) ACC_PROTECTED, ACC_FINAL
    Signature: TB;

  protected void <init>();
    descriptor: (Lio/netty/bootstrap/AbstractBootstrap;)V
    flags: (0x0004) ACC_PROTECTED
    Code:
      stack=3, locals=2, args_size=2
        start local 0 // io.netty.bootstrap.AbstractBootstrapConfig this
        start local 1 // io.netty.bootstrap.AbstractBootstrap bootstrap
         0: .line 36
            aload 0 /* this */
            invokespecial java.lang.Object.<init>:()V
         1: .line 37
            aload 0 /* this */
            aload 1 /* bootstrap */
            ldc "bootstrap"
            invokestatic io.netty.util.internal.ObjectUtil.checkNotNull:(Ljava/lang/Object;Ljava/lang/String;)Ljava/lang/Object;
            checkcast io.netty.bootstrap.AbstractBootstrap
            putfield io.netty.bootstrap.AbstractBootstrapConfig.bootstrap:Lio/netty/bootstrap/AbstractBootstrap;
         2: .line 38
            return
        end local 1 // io.netty.bootstrap.AbstractBootstrap bootstrap
        end local 0 // io.netty.bootstrap.AbstractBootstrapConfig this
      LocalVariableTable:
        Start  End  Slot       Name  Signature
            0    3     0       this  Lio/netty/bootstrap/AbstractBootstrapConfig<TB;TC;>;
            0    3     1  bootstrap  TB;
    Signature: (TB;)V
    MethodParameters:
           Name  Flags
      bootstrap  

  public final java.net.SocketAddress localAddress();
    descriptor: ()Ljava/net/SocketAddress;
    flags: (0x0011) ACC_PUBLIC, ACC_FINAL
    Code:
      stack=1, locals=1, args_size=1
        start local 0 // io.netty.bootstrap.AbstractBootstrapConfig this
         0: .line 44
            aload 0 /* this */
            getfield io.netty.bootstrap.AbstractBootstrapConfig.bootstrap:Lio/netty/bootstrap/AbstractBootstrap;
            invokevirtual io.netty.bootstrap.AbstractBootstrap.localAddress:()Ljava/net/SocketAddress;
            areturn
        end local 0 // io.netty.bootstrap.AbstractBootstrapConfig this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lio/netty/bootstrap/AbstractBootstrapConfig<TB;TC;>;

  public final io.netty.bootstrap.ChannelFactory<? extends C> channelFactory();
    descriptor: ()Lio/netty/bootstrap/ChannelFactory;
    flags: (0x0011) ACC_PUBLIC, ACC_FINAL
    Code:
      stack=1, locals=1, args_size=1
        start local 0 // io.netty.bootstrap.AbstractBootstrapConfig this
         0: .line 52
            aload 0 /* this */
            getfield io.netty.bootstrap.AbstractBootstrapConfig.bootstrap:Lio/netty/bootstrap/AbstractBootstrap;
            invokevirtual io.netty.bootstrap.AbstractBootstrap.channelFactory:()Lio/netty/bootstrap/ChannelFactory;
            areturn
        end local 0 // io.netty.bootstrap.AbstractBootstrapConfig this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lio/netty/bootstrap/AbstractBootstrapConfig<TB;TC;>;
    Signature: ()Lio/netty/bootstrap/ChannelFactory<+TC;>;

  public final io.netty.channel.ChannelHandler handler();
    descriptor: ()Lio/netty/channel/ChannelHandler;
    flags: (0x0011) ACC_PUBLIC, ACC_FINAL
    Code:
      stack=1, locals=1, args_size=1
        start local 0 // io.netty.bootstrap.AbstractBootstrapConfig this
         0: .line 59
            aload 0 /* this */
            getfield io.netty.bootstrap.AbstractBootstrapConfig.bootstrap:Lio/netty/bootstrap/AbstractBootstrap;
            invokevirtual io.netty.bootstrap.AbstractBootstrap.handler:()Lio/netty/channel/ChannelHandler;
            areturn
        end local 0 // io.netty.bootstrap.AbstractBootstrapConfig this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lio/netty/bootstrap/AbstractBootstrapConfig<TB;TC;>;

  public final java.util.Map<io.netty.channel.ChannelOption<?>, java.lang.Object> options();
    descriptor: ()Ljava/util/Map;
    flags: (0x0011) ACC_PUBLIC, ACC_FINAL
    Code:
      stack=1, locals=1, args_size=1
        start local 0 // io.netty.bootstrap.AbstractBootstrapConfig this
         0: .line 66
            aload 0 /* this */
            getfield io.netty.bootstrap.AbstractBootstrapConfig.bootstrap:Lio/netty/bootstrap/AbstractBootstrap;
            invokevirtual io.netty.bootstrap.AbstractBootstrap.options:()Ljava/util/Map;
            areturn
        end local 0 // io.netty.bootstrap.AbstractBootstrapConfig this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lio/netty/bootstrap/AbstractBootstrapConfig<TB;TC;>;
    Signature: ()Ljava/util/Map<Lio/netty/channel/ChannelOption<*>;Ljava/lang/Object;>;

  public final java.util.Map<io.netty.util.AttributeKey<?>, java.lang.Object> attrs();
    descriptor: ()Ljava/util/Map;
    flags: (0x0011) ACC_PUBLIC, ACC_FINAL
    Code:
      stack=1, locals=1, args_size=1
        start local 0 // io.netty.bootstrap.AbstractBootstrapConfig this
         0: .line 73
            aload 0 /* this */
            getfield io.netty.bootstrap.AbstractBootstrapConfig.bootstrap:Lio/netty/bootstrap/AbstractBootstrap;
            invokevirtual io.netty.bootstrap.AbstractBootstrap.attrs:()Ljava/util/Map;
            areturn
        end local 0 // io.netty.bootstrap.AbstractBootstrapConfig this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lio/netty/bootstrap/AbstractBootstrapConfig<TB;TC;>;
    Signature: ()Ljava/util/Map<Lio/netty/util/AttributeKey<*>;Ljava/lang/Object;>;

  public final io.netty.channel.EventLoopGroup group();
    descriptor: ()Lio/netty/channel/EventLoopGroup;
    flags: (0x0011) ACC_PUBLIC, ACC_FINAL
    Code:
      stack=1, locals=1, args_size=1
        start local 0 // io.netty.bootstrap.AbstractBootstrapConfig this
         0: .line 81
            aload 0 /* this */
            getfield io.netty.bootstrap.AbstractBootstrapConfig.bootstrap:Lio/netty/bootstrap/AbstractBootstrap;
            invokevirtual io.netty.bootstrap.AbstractBootstrap.group:()Lio/netty/channel/EventLoopGroup;
            areturn
        end local 0 // io.netty.bootstrap.AbstractBootstrapConfig this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lio/netty/bootstrap/AbstractBootstrapConfig<TB;TC;>;

  public java.lang.String toString();
    descriptor: ()Ljava/lang/String;
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=3, locals=8, args_size=1
        start local 0 // io.netty.bootstrap.AbstractBootstrapConfig this
         0: .line 86
            new java.lang.StringBuilder
            dup
            invokespecial java.lang.StringBuilder.<init>:()V
         1: .line 87
            aload 0 /* this */
            invokestatic io.netty.util.internal.StringUtil.simpleClassName:(Ljava/lang/Object;)Ljava/lang/String;
            invokevirtual java.lang.StringBuilder.append:(Ljava/lang/String;)Ljava/lang/StringBuilder;
         2: .line 88
            bipush 40
            invokevirtual java.lang.StringBuilder.append:(C)Ljava/lang/StringBuilder;
         3: .line 86
            astore 1 /* buf */
        start local 1 // java.lang.StringBuilder buf
         4: .line 89
            aload 0 /* this */
            invokevirtual io.netty.bootstrap.AbstractBootstrapConfig.group:()Lio/netty/channel/EventLoopGroup;
            astore 2 /* group */
        start local 2 // io.netty.channel.EventLoopGroup group
         5: .line 90
            aload 2 /* group */
            ifnull 9
         6: .line 91
            aload 1 /* buf */
            ldc "group: "
            invokevirtual java.lang.StringBuilder.append:(Ljava/lang/String;)Ljava/lang/StringBuilder;
         7: .line 92
            aload 2 /* group */
            invokestatic io.netty.util.internal.StringUtil.simpleClassName:(Ljava/lang/Object;)Ljava/lang/String;
            invokevirtual java.lang.StringBuilder.append:(Ljava/lang/String;)Ljava/lang/StringBuilder;
         8: .line 93
            ldc ", "
            invokevirtual java.lang.StringBuilder.append:(Ljava/lang/String;)Ljava/lang/StringBuilder;
            pop
         9: .line 96
      StackMap locals: java.lang.StringBuilder io.netty.channel.EventLoopGroup
      StackMap stack:
            aload 0 /* this */
            invokevirtual io.netty.bootstrap.AbstractBootstrapConfig.channelFactory:()Lio/netty/bootstrap/ChannelFactory;
            astore 3 /* factory */
        start local 3 // io.netty.bootstrap.ChannelFactory factory
        10: .line 97
            aload 3 /* factory */
            ifnull 14
        11: .line 98
            aload 1 /* buf */
            ldc "channelFactory: "
            invokevirtual java.lang.StringBuilder.append:(Ljava/lang/String;)Ljava/lang/StringBuilder;
        12: .line 99
            aload 3 /* factory */
            invokevirtual java.lang.StringBuilder.append:(Ljava/lang/Object;)Ljava/lang/StringBuilder;
        13: .line 100
            ldc ", "
            invokevirtual java.lang.StringBuilder.append:(Ljava/lang/String;)Ljava/lang/StringBuilder;
            pop
        14: .line 102
      StackMap locals: io.netty.bootstrap.ChannelFactory
      StackMap stack:
            aload 0 /* this */
            invokevirtual io.netty.bootstrap.AbstractBootstrapConfig.localAddress:()Ljava/net/SocketAddress;
            astore 4 /* localAddress */
        start local 4 // java.net.SocketAddress localAddress
        15: .line 103
            aload 4 /* localAddress */
            ifnull 19
        16: .line 104
            aload 1 /* buf */
            ldc "localAddress: "
            invokevirtual java.lang.StringBuilder.append:(Ljava/lang/String;)Ljava/lang/StringBuilder;
        17: .line 105
            aload 4 /* localAddress */
            invokevirtual java.lang.StringBuilder.append:(Ljava/lang/Object;)Ljava/lang/StringBuilder;
        18: .line 106
            ldc ", "
            invokevirtual java.lang.StringBuilder.append:(Ljava/lang/String;)Ljava/lang/StringBuilder;
            pop
        19: .line 109
      StackMap locals: java.net.SocketAddress
      StackMap stack:
            aload 0 /* this */
            invokevirtual io.netty.bootstrap.AbstractBootstrapConfig.options:()Ljava/util/Map;
            astore 5 /* options */
        start local 5 // java.util.Map options
        20: .line 110
            aload 5 /* options */
            invokeinterface java.util.Map.isEmpty:()Z
            ifne 24
        21: .line 111
            aload 1 /* buf */
            ldc "options: "
            invokevirtual java.lang.StringBuilder.append:(Ljava/lang/String;)Ljava/lang/StringBuilder;
        22: .line 112
            aload 5 /* options */
            invokevirtual java.lang.StringBuilder.append:(Ljava/lang/Object;)Ljava/lang/StringBuilder;
        23: .line 113
            ldc ", "
            invokevirtual java.lang.StringBuilder.append:(Ljava/lang/String;)Ljava/lang/StringBuilder;
            pop
        24: .line 115
      StackMap locals: java.util.Map
      StackMap stack:
            aload 0 /* this */
            invokevirtual io.netty.bootstrap.AbstractBootstrapConfig.attrs:()Ljava/util/Map;
            astore 6 /* attrs */
        start local 6 // java.util.Map attrs
        25: .line 116
            aload 6 /* attrs */
            invokeinterface java.util.Map.isEmpty:()Z
            ifne 29
        26: .line 117
            aload 1 /* buf */
            ldc "attrs: "
            invokevirtual java.lang.StringBuilder.append:(Ljava/lang/String;)Ljava/lang/StringBuilder;
        27: .line 118
            aload 6 /* attrs */
            invokevirtual java.lang.StringBuilder.append:(Ljava/lang/Object;)Ljava/lang/StringBuilder;
        28: .line 119
            ldc ", "
            invokevirtual java.lang.StringBuilder.append:(Ljava/lang/String;)Ljava/lang/StringBuilder;
            pop
        29: .line 121
      StackMap locals: java.util.Map
      StackMap stack:
            aload 0 /* this */
            invokevirtual io.netty.bootstrap.AbstractBootstrapConfig.handler:()Lio/netty/channel/ChannelHandler;
            astore 7 /* handler */
        start local 7 // io.netty.channel.ChannelHandler handler
        30: .line 122
            aload 7 /* handler */
            ifnull 34
        31: .line 123
            aload 1 /* buf */
            ldc "handler: "
            invokevirtual java.lang.StringBuilder.append:(Ljava/lang/String;)Ljava/lang/StringBuilder;
        32: .line 124
            aload 7 /* handler */
            invokevirtual java.lang.StringBuilder.append:(Ljava/lang/Object;)Ljava/lang/StringBuilder;
        33: .line 125
            ldc ", "
            invokevirtual java.lang.StringBuilder.append:(Ljava/lang/String;)Ljava/lang/StringBuilder;
            pop
        34: .line 127
      StackMap locals: io.netty.channel.ChannelHandler
      StackMap stack:
            aload 1 /* buf */
            aload 1 /* buf */
            invokevirtual java.lang.StringBuilder.length:()I
            iconst_1
            isub
            invokevirtual java.lang.StringBuilder.charAt:(I)C
            bipush 40
            if_icmpne 37
        35: .line 128
            aload 1 /* buf */
            bipush 41
            invokevirtual java.lang.StringBuilder.append:(C)Ljava/lang/StringBuilder;
            pop
        36: .line 129
            goto 39
        37: .line 130
      StackMap locals:
      StackMap stack:
            aload 1 /* buf */
            aload 1 /* buf */
            invokevirtual java.lang.StringBuilder.length:()I
            iconst_2
            isub
            bipush 41
            invokevirtual java.lang.StringBuilder.setCharAt:(IC)V
        38: .line 131
            aload 1 /* buf */
            aload 1 /* buf */
            invokevirtual java.lang.StringBuilder.length:()I
            iconst_1
            isub
            invokevirtual java.lang.StringBuilder.setLength:(I)V
        39: .line 133
      StackMap locals:
      StackMap stack:
            aload 1 /* buf */
            invokevirtual java.lang.StringBuilder.toString:()Ljava/lang/String;
            areturn
        end local 7 // io.netty.channel.ChannelHandler handler
        end local 6 // java.util.Map attrs
        end local 5 // java.util.Map options
        end local 4 // java.net.SocketAddress localAddress
        end local 3 // io.netty.bootstrap.ChannelFactory factory
        end local 2 // io.netty.channel.EventLoopGroup group
        end local 1 // java.lang.StringBuilder buf
        end local 0 // io.netty.bootstrap.AbstractBootstrapConfig this
      LocalVariableTable:
        Start  End  Slot          Name  Signature
            0   40     0          this  Lio/netty/bootstrap/AbstractBootstrapConfig<TB;TC;>;
            4   40     1           buf  Ljava/lang/StringBuilder;
            5   40     2         group  Lio/netty/channel/EventLoopGroup;
           10   40     3       factory  Lio/netty/bootstrap/ChannelFactory<+TC;>;
           15   40     4  localAddress  Ljava/net/SocketAddress;
           20   40     5       options  Ljava/util/Map<Lio/netty/channel/ChannelOption<*>;Ljava/lang/Object;>;
           25   40     6         attrs  Ljava/util/Map<Lio/netty/util/AttributeKey<*>;Ljava/lang/Object;>;
           30   40     7       handler  Lio/netty/channel/ChannelHandler;
}
Signature: <B:Lio/netty/bootstrap/AbstractBootstrap<TB;TC;>;C::Lio/netty/channel/Channel;>Ljava/lang/Object;
SourceFile: "AbstractBootstrapConfig.java"