/*******************************************************************************
* Copyright (c) 2008 xored software, Inc.
*
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Contributors:
* xored software, Inc. - initial API and Implementation (Alex Panchenko)
*******************************************************************************/
package org.eclipse.dltk.utils;
import java.util.EmptyStackException;
public class CharacterStack {
private char[] buffer;
private int size;
public CharacterStack() {
this(16);
}
/**
* @param capacity
*/
public CharacterStack(int capacity) {
buffer = new char[capacity];
size = 0;
}
/**
* @return
*/
public int size() {
return size;
}
/**
* @return
*/
public boolean isEmpty() {
return size == 0;
}
/**
* @return
*/
public char peek() {
final int len = size;
if (size == 0) {
throw new EmptyStackException();
}
return buffer[len - 1];
}
/**
* @return
*/
public char pop() {
int len = size;
if (len == 0) {
throw new EmptyStackException();
}
--len;
final char result = buffer[len];
size = len;
return result;
}
/**
* @param c
*/
public void push(char c) {
if (size == buffer.length) {
char[] newBuffer = new char[buffer.length * 2 + 1];
System.arraycopy(buffer, 0, newBuffer, 0, buffer.length);
buffer = newBuffer;
}
buffer[size++] = c;
}
}