java.util.Stack
Stack
extends Vector
with five operations that allow a vector to be
treated as a stack. The usual push
and pop
operations are provided, as well as a
method to peek
at the top item on the stack, a method to test for whether the stack
is empty
, and a method to search
the stack for an item and discover how far it is
from the top.
public classWhen a stack is first created, it contains no items.Stack
extends Vector { public Objectpush
(Object item); public Objectpop
() throws EmptyStackException; public Objectpeek
() throws EmptyStackException; public booleanempty
(); public intsearch
(Object o); }
21.12.1 public Object
push
(Object item)
The item
is pushed onto the top of this stack. This has exactly the same effect as:
addElement(item)See method
addElement
of Vector
(§21.11.13).21.12.2 public Object
pop
() throws EmptyStackException
If the stack is empty, an EmptyStackException
is thrown. Otherwise, the topmost
item (last item of the Vector
) is removed and returned.
21.12.3 public Object
peek
() throws EmptyStackException
If the stack is empty, an EmptyStackException
is thrown. Otherwise, the topmost
item (last item of the Vector
) is returned but not removed.
21.12.4 public boolean
empty
()
The result is true
if and only if the stack contains no items.
21.12.5 public int
search
(Object o)
If the object o
occurs as an item in this Stack
, this method returns the distance
from the top of the stack of the occurrence nearest the top of the stack; the topmost
item on the stack is considered to be at distance 1
. The equals
method
(§20.1.3) is used to compare o
to the items in this Stack
.
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Java Language Specification (HTML generated by Suzette Pelouch on February 24, 1998)
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