https://github.com/javaee/jpa-spec: Java(TM) Persistence API 
public interface javax.persistence.metamodel.SingularAttribute<X, T> extends javax.persistence.metamodel.Attribute<X, T>, javax.persistence.metamodel.Bindable<T>
  minor version: 0
  major version: 59
  flags: flags: (0x0601) ACC_PUBLIC, ACC_INTERFACE, ACC_ABSTRACT
  this_class: javax.persistence.metamodel.SingularAttribute
  super_class: java.lang.Object
{
  public abstract boolean isId();
    descriptor: ()Z
    flags: (0x0401) ACC_PUBLIC, ACC_ABSTRACT

  public abstract boolean isVersion();
    descriptor: ()Z
    flags: (0x0401) ACC_PUBLIC, ACC_ABSTRACT

  public abstract boolean isOptional();
    descriptor: ()Z
    flags: (0x0401) ACC_PUBLIC, ACC_ABSTRACT

  public abstract javax.persistence.metamodel.Type<T> getType();
    descriptor: ()Ljavax/persistence/metamodel/Type;
    flags: (0x0401) ACC_PUBLIC, ACC_ABSTRACT
    Signature: ()Ljavax/persistence/metamodel/Type<TT;>;
}
Signature: <X:Ljava/lang/Object;T:Ljava/lang/Object;>Ljava/lang/Object;Ljavax/persistence/metamodel/Attribute<TX;TT;>;Ljavax/persistence/metamodel/Bindable<TT;>;
SourceFile: "SingularAttribute.java"