public interface Stack<K>
A stack must provide the classical push(Object) and
pop() operations, but may be also peekable
to some extent: it may provide just the top() function,
or even a more powerful peek(int) method that provides
access to all elements on the stack (indexed from the top, which
has index 0).
| Modifier and Type | Method and Description |
|---|---|
boolean |
isEmpty()
Checks whether the stack is empty.
|
default K |
peek(int i)
Peeks at an element on the stack (optional operation).
|
K |
pop()
Pops the top off the stack.
|
void |
push(K o)
Pushes the given object on the stack.
|
default K |
top()
Peeks at the top of the stack (optional operation).
|
void push(K o)
o - the object that will become the new top of the stack.K pop()
java.util.NoSuchElementException - if the stack is empty.boolean isEmpty()
default K top()
This default implementation returns peek(0).
java.util.NoSuchElementException - if the stack is empty.default K peek(int i)
This default implementation just throws an UnsupportedOperationException.
i - an index from the stop of the stack (0 represents the top).i-th element on the stack.java.lang.IndexOutOfBoundsException - if the designated element does not exist..