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.handler.codec.mqtt.MqttMessage
  minor version: 0
  major version: 59
  flags: flags: (0x0021) ACC_PUBLIC, ACC_SUPER
  this_class: io.netty.handler.codec.mqtt.MqttMessage
  super_class: java.lang.Object
{
  private final io.netty.handler.codec.mqtt.MqttFixedHeader mqttFixedHeader;
    descriptor: Lio/netty/handler/codec/mqtt/MqttFixedHeader;
    flags: (0x0012) ACC_PRIVATE, ACC_FINAL

  private final java.lang.Object variableHeader;
    descriptor: Ljava/lang/Object;
    flags: (0x0012) ACC_PRIVATE, ACC_FINAL

  private final java.lang.Object payload;
    descriptor: Ljava/lang/Object;
    flags: (0x0012) ACC_PRIVATE, ACC_FINAL

  private final io.netty.handler.codec.DecoderResult decoderResult;
    descriptor: Lio/netty/handler/codec/DecoderResult;
    flags: (0x0012) ACC_PRIVATE, ACC_FINAL

  public void <init>(io.netty.handler.codec.mqtt.MqttFixedHeader);
    descriptor: (Lio/netty/handler/codec/mqtt/MqttFixedHeader;)V
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=4, locals=2, args_size=2
        start local 0 // io.netty.handler.codec.mqtt.MqttMessage this
        start local 1 // io.netty.handler.codec.mqtt.MqttFixedHeader mqttFixedHeader
         0: .line 33
            aload 0 /* this */
            aload 1 /* mqttFixedHeader */
            aconst_null
            aconst_null
            invokespecial io.netty.handler.codec.mqtt.MqttMessage.<init>:(Lio/netty/handler/codec/mqtt/MqttFixedHeader;Ljava/lang/Object;Ljava/lang/Object;)V
         1: .line 34
            return
        end local 1 // io.netty.handler.codec.mqtt.MqttFixedHeader mqttFixedHeader
        end local 0 // io.netty.handler.codec.mqtt.MqttMessage this
      LocalVariableTable:
        Start  End  Slot             Name  Signature
            0    2     0             this  Lio/netty/handler/codec/mqtt/MqttMessage;
            0    2     1  mqttFixedHeader  Lio/netty/handler/codec/mqtt/MqttFixedHeader;
    MethodParameters:
                 Name  Flags
      mqttFixedHeader  

  public void <init>(io.netty.handler.codec.mqtt.MqttFixedHeader, java.lang.Object);
    descriptor: (Lio/netty/handler/codec/mqtt/MqttFixedHeader;Ljava/lang/Object;)V
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=4, locals=3, args_size=3
        start local 0 // io.netty.handler.codec.mqtt.MqttMessage this
        start local 1 // io.netty.handler.codec.mqtt.MqttFixedHeader mqttFixedHeader
        start local 2 // java.lang.Object variableHeader
         0: .line 37
            aload 0 /* this */
            aload 1 /* mqttFixedHeader */
            aload 2 /* variableHeader */
            aconst_null
            invokespecial io.netty.handler.codec.mqtt.MqttMessage.<init>:(Lio/netty/handler/codec/mqtt/MqttFixedHeader;Ljava/lang/Object;Ljava/lang/Object;)V
         1: .line 38
            return
        end local 2 // java.lang.Object variableHeader
        end local 1 // io.netty.handler.codec.mqtt.MqttFixedHeader mqttFixedHeader
        end local 0 // io.netty.handler.codec.mqtt.MqttMessage this
      LocalVariableTable:
        Start  End  Slot             Name  Signature
            0    2     0             this  Lio/netty/handler/codec/mqtt/MqttMessage;
            0    2     1  mqttFixedHeader  Lio/netty/handler/codec/mqtt/MqttFixedHeader;
            0    2     2   variableHeader  Ljava/lang/Object;
    MethodParameters:
                 Name  Flags
      mqttFixedHeader  
      variableHeader   

  public void <init>(io.netty.handler.codec.mqtt.MqttFixedHeader, java.lang.Object, java.lang.Object);
    descriptor: (Lio/netty/handler/codec/mqtt/MqttFixedHeader;Ljava/lang/Object;Ljava/lang/Object;)V
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=5, locals=4, args_size=4
        start local 0 // io.netty.handler.codec.mqtt.MqttMessage this
        start local 1 // io.netty.handler.codec.mqtt.MqttFixedHeader mqttFixedHeader
        start local 2 // java.lang.Object variableHeader
        start local 3 // java.lang.Object payload
         0: .line 41
            aload 0 /* this */
            aload 1 /* mqttFixedHeader */
            aload 2 /* variableHeader */
            aload 3 /* payload */
            getstatic io.netty.handler.codec.DecoderResult.SUCCESS:Lio/netty/handler/codec/DecoderResult;
            invokespecial io.netty.handler.codec.mqtt.MqttMessage.<init>:(Lio/netty/handler/codec/mqtt/MqttFixedHeader;Ljava/lang/Object;Ljava/lang/Object;Lio/netty/handler/codec/DecoderResult;)V
         1: .line 42
            return
        end local 3 // java.lang.Object payload
        end local 2 // java.lang.Object variableHeader
        end local 1 // io.netty.handler.codec.mqtt.MqttFixedHeader mqttFixedHeader
        end local 0 // io.netty.handler.codec.mqtt.MqttMessage this
      LocalVariableTable:
        Start  End  Slot             Name  Signature
            0    2     0             this  Lio/netty/handler/codec/mqtt/MqttMessage;
            0    2     1  mqttFixedHeader  Lio/netty/handler/codec/mqtt/MqttFixedHeader;
            0    2     2   variableHeader  Ljava/lang/Object;
            0    2     3          payload  Ljava/lang/Object;
    MethodParameters:
                 Name  Flags
      mqttFixedHeader  
      variableHeader   
      payload          

  public void <init>(io.netty.handler.codec.mqtt.MqttFixedHeader, java.lang.Object, java.lang.Object, io.netty.handler.codec.DecoderResult);
    descriptor: (Lio/netty/handler/codec/mqtt/MqttFixedHeader;Ljava/lang/Object;Ljava/lang/Object;Lio/netty/handler/codec/DecoderResult;)V
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=2, locals=5, args_size=5
        start local 0 // io.netty.handler.codec.mqtt.MqttMessage this
        start local 1 // io.netty.handler.codec.mqtt.MqttFixedHeader mqttFixedHeader
        start local 2 // java.lang.Object variableHeader
        start local 3 // java.lang.Object payload
        start local 4 // io.netty.handler.codec.DecoderResult decoderResult
         0: .line 44
            aload 0 /* this */
            invokespecial java.lang.Object.<init>:()V
         1: .line 49
            aload 0 /* this */
            aload 1 /* mqttFixedHeader */
            putfield io.netty.handler.codec.mqtt.MqttMessage.mqttFixedHeader:Lio/netty/handler/codec/mqtt/MqttFixedHeader;
         2: .line 50
            aload 0 /* this */
            aload 2 /* variableHeader */
            putfield io.netty.handler.codec.mqtt.MqttMessage.variableHeader:Ljava/lang/Object;
         3: .line 51
            aload 0 /* this */
            aload 3 /* payload */
            putfield io.netty.handler.codec.mqtt.MqttMessage.payload:Ljava/lang/Object;
         4: .line 52
            aload 0 /* this */
            aload 4 /* decoderResult */
            putfield io.netty.handler.codec.mqtt.MqttMessage.decoderResult:Lio/netty/handler/codec/DecoderResult;
         5: .line 53
            return
        end local 4 // io.netty.handler.codec.DecoderResult decoderResult
        end local 3 // java.lang.Object payload
        end local 2 // java.lang.Object variableHeader
        end local 1 // io.netty.handler.codec.mqtt.MqttFixedHeader mqttFixedHeader
        end local 0 // io.netty.handler.codec.mqtt.MqttMessage this
      LocalVariableTable:
        Start  End  Slot             Name  Signature
            0    6     0             this  Lio/netty/handler/codec/mqtt/MqttMessage;
            0    6     1  mqttFixedHeader  Lio/netty/handler/codec/mqtt/MqttFixedHeader;
            0    6     2   variableHeader  Ljava/lang/Object;
            0    6     3          payload  Ljava/lang/Object;
            0    6     4    decoderResult  Lio/netty/handler/codec/DecoderResult;
    MethodParameters:
                 Name  Flags
      mqttFixedHeader  
      variableHeader   
      payload          
      decoderResult    

  public io.netty.handler.codec.mqtt.MqttFixedHeader fixedHeader();
    descriptor: ()Lio/netty/handler/codec/mqtt/MqttFixedHeader;
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=1, locals=1, args_size=1
        start local 0 // io.netty.handler.codec.mqtt.MqttMessage this
         0: .line 56
            aload 0 /* this */
            getfield io.netty.handler.codec.mqtt.MqttMessage.mqttFixedHeader:Lio/netty/handler/codec/mqtt/MqttFixedHeader;
            areturn
        end local 0 // io.netty.handler.codec.mqtt.MqttMessage this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lio/netty/handler/codec/mqtt/MqttMessage;

  public java.lang.Object variableHeader();
    descriptor: ()Ljava/lang/Object;
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=1, locals=1, args_size=1
        start local 0 // io.netty.handler.codec.mqtt.MqttMessage this
         0: .line 60
            aload 0 /* this */
            getfield io.netty.handler.codec.mqtt.MqttMessage.variableHeader:Ljava/lang/Object;
            areturn
        end local 0 // io.netty.handler.codec.mqtt.MqttMessage this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lio/netty/handler/codec/mqtt/MqttMessage;

  public java.lang.Object payload();
    descriptor: ()Ljava/lang/Object;
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=1, locals=1, args_size=1
        start local 0 // io.netty.handler.codec.mqtt.MqttMessage this
         0: .line 64
            aload 0 /* this */
            getfield io.netty.handler.codec.mqtt.MqttMessage.payload:Ljava/lang/Object;
            areturn
        end local 0 // io.netty.handler.codec.mqtt.MqttMessage this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lio/netty/handler/codec/mqtt/MqttMessage;

  public io.netty.handler.codec.DecoderResult decoderResult();
    descriptor: ()Lio/netty/handler/codec/DecoderResult;
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=1, locals=1, args_size=1
        start local 0 // io.netty.handler.codec.mqtt.MqttMessage this
         0: .line 68
            aload 0 /* this */
            getfield io.netty.handler.codec.mqtt.MqttMessage.decoderResult:Lio/netty/handler/codec/DecoderResult;
            areturn
        end local 0 // io.netty.handler.codec.mqtt.MqttMessage this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lio/netty/handler/codec/mqtt/MqttMessage;

  public java.lang.String toString();
    descriptor: ()Ljava/lang/String;
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=3, locals=1, args_size=1
        start local 0 // io.netty.handler.codec.mqtt.MqttMessage this
         0: .line 73
            new java.lang.StringBuilder
            dup
            aload 0 /* this */
            invokestatic io.netty.util.internal.StringUtil.simpleClassName:(Ljava/lang/Object;)Ljava/lang/String;
            invokespecial java.lang.StringBuilder.<init>:(Ljava/lang/String;)V
         1: .line 74
            bipush 91
            invokevirtual java.lang.StringBuilder.append:(C)Ljava/lang/StringBuilder;
         2: .line 75
            ldc "fixedHeader="
            invokevirtual java.lang.StringBuilder.append:(Ljava/lang/String;)Ljava/lang/StringBuilder;
            aload 0 /* this */
            invokevirtual io.netty.handler.codec.mqtt.MqttMessage.fixedHeader:()Lio/netty/handler/codec/mqtt/MqttFixedHeader;
            ifnull 3
            aload 0 /* this */
            invokevirtual io.netty.handler.codec.mqtt.MqttMessage.fixedHeader:()Lio/netty/handler/codec/mqtt/MqttFixedHeader;
            invokevirtual io.netty.handler.codec.mqtt.MqttFixedHeader.toString:()Ljava/lang/String;
            goto 4
      StackMap locals:
      StackMap stack: java.lang.StringBuilder
         3: ldc ""
      StackMap locals: io.netty.handler.codec.mqtt.MqttMessage
      StackMap stack: java.lang.StringBuilder java.lang.String
         4: invokevirtual java.lang.StringBuilder.append:(Ljava/lang/String;)Ljava/lang/StringBuilder;
         5: .line 76
            ldc ", variableHeader="
            invokevirtual java.lang.StringBuilder.append:(Ljava/lang/String;)Ljava/lang/StringBuilder;
            aload 0 /* this */
            invokevirtual io.netty.handler.codec.mqtt.MqttMessage.variableHeader:()Ljava/lang/Object;
            ifnull 6
            aload 0 /* this */
            getfield io.netty.handler.codec.mqtt.MqttMessage.variableHeader:Ljava/lang/Object;
            invokevirtual java.lang.Object.toString:()Ljava/lang/String;
            goto 7
      StackMap locals:
      StackMap stack: java.lang.StringBuilder
         6: ldc ""
      StackMap locals: io.netty.handler.codec.mqtt.MqttMessage
      StackMap stack: java.lang.StringBuilder java.lang.String
         7: invokevirtual java.lang.StringBuilder.append:(Ljava/lang/String;)Ljava/lang/StringBuilder;
         8: .line 77
            ldc ", payload="
            invokevirtual java.lang.StringBuilder.append:(Ljava/lang/String;)Ljava/lang/StringBuilder;
            aload 0 /* this */
            invokevirtual io.netty.handler.codec.mqtt.MqttMessage.payload:()Ljava/lang/Object;
            ifnull 9
            aload 0 /* this */
            getfield io.netty.handler.codec.mqtt.MqttMessage.payload:Ljava/lang/Object;
            invokevirtual java.lang.Object.toString:()Ljava/lang/String;
            goto 10
      StackMap locals:
      StackMap stack: java.lang.StringBuilder
         9: ldc ""
      StackMap locals: io.netty.handler.codec.mqtt.MqttMessage
      StackMap stack: java.lang.StringBuilder java.lang.String
        10: invokevirtual java.lang.StringBuilder.append:(Ljava/lang/String;)Ljava/lang/StringBuilder;
        11: .line 78
            bipush 93
            invokevirtual java.lang.StringBuilder.append:(C)Ljava/lang/StringBuilder;
        12: .line 79
            invokevirtual java.lang.StringBuilder.toString:()Ljava/lang/String;
        13: .line 73
            areturn
        end local 0 // io.netty.handler.codec.mqtt.MqttMessage this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0   14     0  this  Lio/netty/handler/codec/mqtt/MqttMessage;
}
SourceFile: "MqttMessage.java"