Answer Posted / naveen

There is null check in the put method implementation of
hashtable, so it does not support null values and null keys.


public Object put(Object key, Object value) {
// Make sure the value is not null
if (value == null) throw new NullPointerException();
}

above is HashTable put method logic implemented by Sun.

What is the major difference between linkedlist and arraylist?

1035

---

Can we compare two strings in java?

1018

---

What are the different ways of creating thread?

1005

---

Does list maintain insertion order java?

905

---

What are the steps involved to create a bean?

1150

---

Define locale.

1036

---

Can we extend immutable class?

976

---

What is the difference between throw and throws keywords?

1047

---

What is e in java?

957

---

Why are parameters used in functions?

1011

---

What is a byte array?

1095

---

What is role of void keyword in declaring functions?

1046

---

why are wait(), notify() and notifyall() methods defined in the object class? : Java thread

984

---

What are runtime exceptions?

1155

---

What is the difference between actual and formal parameters?

941

---