package org.eclipse.jdt.internal.core.index.impl;
/*
 * (c) Copyright IBM Corp. 2000, 2001.
 * All Rights Reserved.
 */
import org.eclipse.jdt.core.*;

public final class ObjectVector {
	static int INITIAL_SIZE= 10;

	public int size;
	int maxSize;
	Object[] elements;
	public ObjectVector() {
		maxSize= INITIAL_SIZE;
		size= 0;
		elements= new Object[maxSize];
	}
	public void add(Object newElement) {
		if (size == maxSize) // knows that size starts <= maxSize
			System.arraycopy(elements, 0, (elements= new Object[maxSize *= 2]), 0, size);
		elements[size++]= newElement;
	}
	public void addAll(Object[] newElements) {
		if (size + newElements.length >= maxSize) {
			maxSize= size + newElements.length; // assume no more elements will be added
			System.arraycopy(elements, 0, (elements= new Object[maxSize]), 0, size);
		}
		System.arraycopy(newElements, 0, elements, size, newElements.length);
		size += newElements.length;
	}
	public boolean contains(Object element) {
		for (int i= size; --i >= 0;)
			if (element == elements[i])
				return true;
		return false;
	}
	public Object elementAt(int index) {
		return elements[index];
	}
	public Object find(Object element) {
		for (int i= size; --i >= 0;)
			if (element == elements[i])
				return elements[i];
		return null;
	}
	public Object remove(Object element) {
		// assumes only one occurrence of the element exists
		for (int i= size; --i >= 0;)
			if (element == elements[i]) {
				// shift the remaining elements down one spot
				System.arraycopy(elements, i + 1, elements, i, --size - i);
				elements[size]= null;
				return element;
			}
		return null;
	}
	public void removeAll() {
		for (int i= size; --i >= 0;)
			elements[i]= null;
		size= 0;
	}
	public String toString() {
		String s= ""/*nonNLS*/;
		for (int i= 0; i < size; i++)
			s += elements[i].toString() + "\n"/*nonNLS*/;
		return s;
	}
}