src/main/java/org/criteria4jpa/criterion/Restrictions.java
public static Criterion memberOf(String relativePath, Object value) {
    return new MemberOfExpression(relativePath, value, false);
  }
public static Criterion memberOf(String relativePath, Object value) {
    return new MemberOfExpression(relativePath, value, false);
  }
Creates a "member of" restriction.

@param relativePath relative path of a collection
@param value The value to check membership for
@return new {@link Criterion} instance