https://www.graalvm.org/ 
class org.graalvm.compiler.replacements.test.FoldTest$TestMethodSubstitution
  minor version: 0
  major version: 59
  flags: flags: (0x0020) ACC_SUPER
  this_class: org.graalvm.compiler.replacements.test.FoldTest$TestMethodSubstitution
  super_class: java.lang.Object
{
  private static final org.graalvm.compiler.replacements.test.FoldTest$FoldUtils utils;
    descriptor: Lorg/graalvm/compiler/replacements/test/FoldTest$FoldUtils;
    flags: (0x001a) ACC_PRIVATE, ACC_STATIC, ACC_FINAL

  static void <clinit>();
    descriptor: ()V
    flags: (0x0008) ACC_STATIC
    Code:
      stack=3, locals=0, args_size=0
         0: .line 74
            new org.graalvm.compiler.replacements.test.FoldTest$FoldUtils
            dup
            bipush 21
            invokespecial org.graalvm.compiler.replacements.test.FoldTest$FoldUtils.<init>:(I)V
            putstatic org.graalvm.compiler.replacements.test.FoldTest$TestMethodSubstitution.utils:Lorg/graalvm/compiler/replacements/test/FoldTest$FoldUtils;
            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 // org.graalvm.compiler.replacements.test.FoldTest$TestMethodSubstitution this
         0: .line 72
            aload 0 /* this */
            invokespecial java.lang.Object.<init>:()V
            return
        end local 0 // org.graalvm.compiler.replacements.test.FoldTest$TestMethodSubstitution this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lorg/graalvm/compiler/replacements/test/FoldTest$TestMethodSubstitution;

  public static int test();
    descriptor: ()I
    flags: (0x0009) ACC_PUBLIC, ACC_STATIC
    Code:
      stack=2, locals=0, args_size=0
         0: .line 78
            getstatic org.graalvm.compiler.replacements.test.FoldTest$TestMethodSubstitution.utils:Lorg/graalvm/compiler/replacements/test/FoldTest$FoldUtils;
            invokevirtual org.graalvm.compiler.replacements.test.FoldTest$FoldUtils.getNumber:()I
            iconst_2
            invokestatic org.graalvm.compiler.replacements.test.FoldTest$FoldUtils.multiply:(II)I
            ireturn
      LocalVariableTable:
        Start  End  Slot  Name  Signature
    RuntimeVisibleAnnotations: 
      org.graalvm.compiler.api.replacements.MethodSubstitution()
}
SourceFile: "FoldTest.java"
NestHost: org.graalvm.compiler.replacements.test.FoldTest
InnerClasses:
  FoldUtils = org.graalvm.compiler.replacements.test.FoldTest$FoldUtils of org.graalvm.compiler.replacements.test.FoldTest
  private TestMethodSubstitution = org.graalvm.compiler.replacements.test.FoldTest$TestMethodSubstitution of org.graalvm.compiler.replacements.test.FoldTest
    RuntimeVisibleAnnotations: 
      org.graalvm.compiler.api.replacements.ClassSubstitution(value = Lorg/graalvm/compiler/replacements/test/FoldTest$TestMethod;)