code: @NullSafe
    public static boolean equalsIgnoreNull(Object obj1, Object obj2) {
      return obj1 == null ? obj2 == null : obj1.equals(obj2);
    }
docs: Determines whether two objects are equal in value as determined by the Object.equals method.  Both objects are
  considered equal if and only if both are null or obj1.equals(obj2).
  
  @param obj1 the first Object in the equality comparison.
  @param obj2 the second Object in the equality comparison.
  @return a boolean value indicating whether the two Objects are equal in value where two null Object references
  are considered equal as well.
  @see java.lang.Object#equals(Object)