it.unimi.dsi.fastutil
Class AbstractStack

java.lang.Object
  it.unimi.dsi.fastutil.AbstractStack

All Implemented Interfaces:

Stack

Direct Known Subclasses:

AbstractBooleanStack, AbstractByteStack, AbstractCharStack, AbstractDoubleStack, AbstractFloatStack, AbstractIntStack, AbstractLongStack, AbstractShortStack

public abstract class AbstractStack

extends Object

implements Stack

An abstract class providing basic methods for implementing the Stack interface.

This class just defines Stack.top() as peek(0), and Stack.peek(int) as throwing an UnsupportedOperationException. Subclasses of this class may choose to implement just Stack.push(Object), Stack.pop() and Stack.isEmpty(), or (but this is not required) go farther and implement Stack.top(), or even Stack.peek(int).

Constructor Summary

AbstractStack()

Method Summary

Object	peek(int i) Peeks at an element on the stack (optional operation).
Object	top() Peeks at the top of the stack (optional operation).

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface it.unimi.dsi.fastutil.Stack

isEmpty, pop, push

Constructor Detail

AbstractStack

public AbstractStack()

Method Detail

top

public Object top()

Description copied from interface: Stack

Peeks at the top of the stack (optional operation).

Specified by:

top in interface Stack

Returns:

the top of the stack.

peek

public Object peek(int i)

Description copied from interface: Stack

Peeks at an element on the stack (optional operation).

Specified by:

peek in interface Stack

Returns:

the i-th element on the stack; 0 represents the top.