Java pit encountered: Comparison of Long type

public static void main(String[] args) {
    Long goodsId=127L;
    Long itemId=127L;
    //true
    System.out.println(goodsId == itemId);
    goodsId=128L;
    itemId=128L;
    //false
    System.out.println(goodsId == itemId);
    Long x=new Long(127);
    Long y=new Long(127);
    //false
    System.out.println(x == y);
    //true
    System.out.println(x.equals(y));
}

Long is a reference type, to compare the size of two Long, must use equals rather than using ==

However, when the Long and the constant value is a constant less than one byte, two Long a constant point to the same content;

Long and constant when constant value greater than one byte, two different constants Long directed content.

Concluded, without reference to the comparison must use equals use ==