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) 
final class io.netty.channel.DefaultSelectStrategy implements io.netty.channel.SelectStrategy
  minor version: 0
  major version: 59
  flags: flags: (0x0030) ACC_FINAL, ACC_SUPER
  this_class: io.netty.channel.DefaultSelectStrategy
  super_class: java.lang.Object
{
  static final io.netty.channel.SelectStrategy INSTANCE;
    descriptor: Lio/netty/channel/SelectStrategy;
    flags: (0x0018) ACC_STATIC, ACC_FINAL

  static void <clinit>();
    descriptor: ()V
    flags: (0x0008) ACC_STATIC
    Code:
      stack=2, locals=0, args_size=0
         0: .line 24
            new io.netty.channel.DefaultSelectStrategy
            dup
            invokespecial io.netty.channel.DefaultSelectStrategy.<init>:()V
            putstatic io.netty.channel.DefaultSelectStrategy.INSTANCE:Lio/netty/channel/SelectStrategy;
            return
      LocalVariableTable:
        Start  End  Slot  Name  Signature

  private void <init>();
    descriptor: ()V
    flags: (0x0002) ACC_PRIVATE
    Code:
      stack=1, locals=1, args_size=1
        start local 0 // io.netty.channel.DefaultSelectStrategy this
         0: .line 26
            aload 0 /* this */
            invokespecial java.lang.Object.<init>:()V
            return
        end local 0 // io.netty.channel.DefaultSelectStrategy this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lio/netty/channel/DefaultSelectStrategy;

  public int calculateStrategy(io.netty.util.IntSupplier, boolean);
    descriptor: (Lio/netty/util/IntSupplier;Z)I
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=1, locals=3, args_size=3
        start local 0 // io.netty.channel.DefaultSelectStrategy this
        start local 1 // io.netty.util.IntSupplier selectSupplier
        start local 2 // boolean hasTasks
         0: .line 30
            iload 2 /* hasTasks */
            ifeq 1
            aload 1 /* selectSupplier */
            invokeinterface io.netty.util.IntSupplier.get:()I
            goto 2
      StackMap locals:
      StackMap stack:
         1: iconst_m1
      StackMap locals:
      StackMap stack: int
         2: ireturn
        end local 2 // boolean hasTasks
        end local 1 // io.netty.util.IntSupplier selectSupplier
        end local 0 // io.netty.channel.DefaultSelectStrategy this
      LocalVariableTable:
        Start  End  Slot            Name  Signature
            0    3     0            this  Lio/netty/channel/DefaultSelectStrategy;
            0    3     1  selectSupplier  Lio/netty/util/IntSupplier;
            0    3     2        hasTasks  Z
    Exceptions:
      throws java.lang.Exception
    MethodParameters:
                Name  Flags
      selectSupplier  
      hasTasks        
}
SourceFile: "DefaultSelectStrategy.java"