https://source.android.com/ 
public abstract class android.service.autofill.InternalValidator implements android.service.autofill.Validator, android.os.Parcelable
  minor version: 0
  major version: 59
  flags: flags: (0x0421) ACC_PUBLIC, ACC_SUPER, ACC_ABSTRACT
  this_class: android.service.autofill.InternalValidator
  super_class: java.lang.Object
{
  public void <init>();
    descriptor: ()V
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=1, locals=1, args_size=1
        start local 0 // android.service.autofill.InternalValidator this
         0: .line 29
            aload 0 /* this */
            invokespecial java.lang.Object.<init>:()V
            return
        end local 0 // android.service.autofill.InternalValidator this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Landroid/service/autofill/InternalValidator;

  public abstract boolean isValid(android.service.autofill.ValueFinder);
    descriptor: (Landroid/service/autofill/ValueFinder;)Z
    flags: (0x0401) ACC_PUBLIC, ACC_ABSTRACT
    MethodParameters:
        Name  Flags
      finder  
}
SourceFile: "InternalValidator.java"