https://eclipse.org/jetty/jetty-util: Utility classes for Jetty (Webtide) 
class org.eclipse.jetty.util.component.Graceful$Shutdown$1 extends java.util.concurrent.CompletableFuture<java.lang.Void>
  minor version: 0
  major version: 59
  flags: flags: (0x0020) ACC_SUPER
  this_class: org.eclipse.jetty.util.component.Graceful$Shutdown$1
  super_class: java.util.concurrent.CompletableFuture
{
  final org.eclipse.jetty.util.component.Graceful$Shutdown this$1;
    descriptor: Lorg/eclipse/jetty/util/component/Graceful$Shutdown;
    flags: (0x1010) ACC_FINAL, ACC_SYNTHETIC

  void <init>(org.eclipse.jetty.util.component.Graceful$Shutdown);
    descriptor: (Lorg/eclipse/jetty/util/component/Graceful$Shutdown;)V
    flags: (0x0000) 
    Code:
      stack=2, locals=2, args_size=2
        start local 0 // org.eclipse.jetty.util.component.Graceful$Shutdown$1 this
         0: .line 82
            aload 0 /* this */
            aload 1
            putfield org.eclipse.jetty.util.component.Graceful$Shutdown$1.this$1:Lorg/eclipse/jetty/util/component/Graceful$Shutdown;
            aload 0 /* this */
            invokespecial java.util.concurrent.CompletableFuture.<init>:()V
            return
        end local 0 // org.eclipse.jetty.util.component.Graceful$Shutdown$1 this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lorg/eclipse/jetty/util/component/Graceful$Shutdown$1;
    MethodParameters:
        Name  Flags
      this$0  final

  public java.lang.String toString();
    descriptor: ()Ljava/lang/String;
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=5, locals=1, args_size=1
        start local 0 // org.eclipse.jetty.util.component.Graceful$Shutdown$1 this
         0: .line 87
            ldc "Shutdown<%s>@%x"
            iconst_2
            anewarray java.lang.Object
            dup
            iconst_0
            aload 0 /* this */
            getfield org.eclipse.jetty.util.component.Graceful$Shutdown$1.this$1:Lorg/eclipse/jetty/util/component/Graceful$Shutdown;
            getfield org.eclipse.jetty.util.component.Graceful$Shutdown._component:Ljava/lang/Object;
            aastore
            dup
            iconst_1
            aload 0 /* this */
            invokevirtual java.lang.Object.hashCode:()I
            invokestatic java.lang.Integer.valueOf:(I)Ljava/lang/Integer;
            aastore
            invokestatic java.lang.String.format:(Ljava/lang/String;[Ljava/lang/Object;)Ljava/lang/String;
            areturn
        end local 0 // org.eclipse.jetty.util.component.Graceful$Shutdown$1 this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lorg/eclipse/jetty/util/component/Graceful$Shutdown$1;
}
Signature: Ljava/util/concurrent/CompletableFuture<Ljava/lang/Void;>;
SourceFile: "Graceful.java"
EnclosingMethod: org.eclipse.jetty.util.component.Graceful$Shutdown.shutdown:()Ljava/util/concurrent/CompletableFuture;
NestHost: org.eclipse.jetty.util.component.Graceful
InnerClasses:
  public abstract Shutdown = org.eclipse.jetty.util.component.Graceful$Shutdown of org.eclipse.jetty.util.component.Graceful
  org.eclipse.jetty.util.component.Graceful$Shutdown$1