https://www.graalvm.org/ 
final class org.graalvm.compiler.graph.Graph$PlaceHolderNode extends org.graalvm.compiler.graph.Node
  minor version: 0
  major version: 59
  flags: flags: (0x0030) ACC_FINAL, ACC_SUPER
  this_class: org.graalvm.compiler.graph.Graph$PlaceHolderNode
  super_class: org.graalvm.compiler.graph.Node
{
  public static final org.graalvm.compiler.graph.NodeClass<org.graalvm.compiler.graph.Graph$PlaceHolderNode> TYPE;
    descriptor: Lorg/graalvm/compiler/graph/NodeClass;
    flags: (0x0019) ACC_PUBLIC, ACC_STATIC, ACC_FINAL
    Signature: Lorg/graalvm/compiler/graph/NodeClass<Lorg/graalvm/compiler/graph/Graph$PlaceHolderNode;>;

  static void <clinit>();
    descriptor: ()V
    flags: (0x0008) ACC_STATIC
    Code:
      stack=1, locals=0, args_size=0
         0: .line 886
            ldc Lorg/graalvm/compiler/graph/Graph$PlaceHolderNode;
            invokestatic org.graalvm.compiler.graph.NodeClass.create:(Ljava/lang/Class;)Lorg/graalvm/compiler/graph/NodeClass;
            putstatic org.graalvm.compiler.graph.Graph$PlaceHolderNode.TYPE:Lorg/graalvm/compiler/graph/NodeClass;
            return
      LocalVariableTable:
        Start  End  Slot  Name  Signature

  protected void <init>();
    descriptor: ()V
    flags: (0x0004) ACC_PROTECTED
    Code:
      stack=2, locals=1, args_size=1
        start local 0 // org.graalvm.compiler.graph.Graph$PlaceHolderNode this
         0: .line 889
            aload 0 /* this */
            getstatic org.graalvm.compiler.graph.Graph$PlaceHolderNode.TYPE:Lorg/graalvm/compiler/graph/NodeClass;
            invokespecial org.graalvm.compiler.graph.Node.<init>:(Lorg/graalvm/compiler/graph/NodeClass;)V
         1: .line 890
            return
        end local 0 // org.graalvm.compiler.graph.Graph$PlaceHolderNode this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    2     0  this  Lorg/graalvm/compiler/graph/Graph$PlaceHolderNode;
}
SourceFile: "Graph.java"
NestHost: org.graalvm.compiler.graph.Graph
InnerClasses:
  final PlaceHolderNode = org.graalvm.compiler.graph.Graph$PlaceHolderNode of org.graalvm.compiler.graph.Graph
    RuntimeVisibleAnnotations: 
      org.graalvm.compiler.nodeinfo.NodeInfo(cycles = org.graalvm.compiler.nodeinfo.NodeCycles.CYCLES_IGNORED:Lorg/graalvm/compiler/nodeinfo/NodeCycles;, size = org.graalvm.compiler.nodeinfo.NodeSize.SIZE_IGNORED:Lorg/graalvm/compiler/nodeinfo/NodeSize;)