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// java.util.Stack -- an implementation of the Java Language Spec sec 21.12
// Written by Charles Briscoe-Smith; refer to the file LEGAL for details.
package java.util;
public class Stack extends Vector {
// PUBLIC INTERFACE
public Object push(Object item)
{
addElement(item);
// FIXME: what should this return??
return item;
}
public synchronized Object pop() throws EmptyStackException
{
if (size()>0) {
Object o=lastElement();
removeElementAt(size()-1);
return o;
} else {
throw new EmptyStackException();
}
}
public Object peek() throws EmptyStackException
{
try {
return lastElement();
} catch (NoSuchElementException e) {
throw new EmptyStackException();
}
}
public boolean empty()
{
return isEmpty();
}
public int search(Object o)
{
int pos=lastIndexOf(o);
if (pos==-1)
/// FIXME: what should this return??
return -1;
else
return size()-pos;
}
}
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