zoo_app/app/src/main/java/com/example/jhalloran/zoo/model/Zoo.java
public void addPen(Enclosable pen) {
    if (!getPens().contains(pen)) {
      UUID newUuid = UUID.randomUUID();
      idsToPens.put(newUuid, pen);
      allItems.put(newUuid, pen);
    }
  }
/**
   * @param pen {@link Enclosable} to add to the Zoo.
   */
@param pen  Enclosable to add to the Zoo.
@param pen Enclosable to add to the Zoo .
public void addPen(Enclosable pen) {
    if (!getPens().contains(pen)) {
      UUID newUuid = UUID.randomUUID();
      idsToPens.put(newUuid, pen);
      allItems.put(newUuid, pen);
    }
  }
public void addPen ( Enclosable pen ) { if ( ! getPens ( ) . contains ( pen ) ) { UUID newUuid = UUID . randomUUID ( ) ; idsToPens . put ( newUuid , pen ) ; allItems . put ( newUuid , pen ) ; } }
@param pen {@link Enclosable} to add to the Zoo.
@param pen { @link Enclosable } to add to the Zoo .