### Question:
Order implements Serializable { @Override public String toString() { return "Order{" + "type=" + type + ", index=" + index + ", price=" + price + ", amount=" + amount + '}'; } protected  Order(int index, OrderType type); protected  Order(int index, OrderType type, Decimal price, Decimal amount); OrderType getType(); boolean isBuy(); boolean isSell(); int getIndex(); Decimal getPrice(); Decimal getAmount(); @Override int hashCode(); @Override boolean equals(Object obj); @Override String toString(); static Order buyAt(int index); static Order buyAt(int index, Decimal price, Decimal amount); static Order sellAt(int index); static Order sellAt(int index, Decimal price, Decimal amount);  }### Answer:
@Test public void overrideToString() { assertEquals(opEquals1.toString(), opEquals2.toString()); assertNotEquals(opEquals1.toString(), opNotEquals1.toString()); assertNotEquals(opEquals1.toString(), opNotEquals2.toString()); }