Copyright (c) 2000, 2008 IBM Corporation and others.
This program and the accompanying materials
are made available under the terms of the Eclipse Public License 2.0
which accompanies this distribution, and is available at
https://www.eclipse.org/legal/epl-2.0/
SPDX-License-Identifier: EPL-2.0
Contributors:
    IBM Corporation - initial API and implementation
/*******************************************************************************
 * Copyright (c) 2000, 2008 IBM Corporation and others.
 *
 * This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License 2.0
 * which accompanies this distribution, and is available at
 * https://www.eclipse.org/legal/epl-2.0/
 *
 * SPDX-License-Identifier: EPL-2.0
 *
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.jdt.internal.compiler.util;

import java.util.Iterator;

public final class ObjectVector implements Iterable<Object> {

	static int INITIAL_SIZE = 10;

	public int size;
	int maxSize;
	Object[] elements;

	public ObjectVector() {
		this(INITIAL_SIZE);
	}

	public ObjectVector(int initialSize) {
		this.maxSize = initialSize > 0 ? initialSize : INITIAL_SIZE;
		this.size = 0;
		this.elements = new Object[this.maxSize];
	}

	public void add(Object newElement) {

		if (this.size == this.maxSize) // knows that size starts <= maxSize
			System.arraycopy(this.elements, 0, (this.elements = new Object[this.maxSize *= 2]), 0, this.size);
		this.elements[this.size++] = newElement;
	}

	public void addAll(Object[] newElements) {

		if (this.size + newElements.length >= this.maxSize) {
			this.maxSize = this.size + newElements.length; // assume no more elements will be added
			System.arraycopy(this.elements, 0, (this.elements = new Object[this.maxSize]), 0, this.size);
		}
		System.arraycopy(newElements, 0, this.elements, this.size, newElements.length);
		this.size += newElements.length;
	}

	public void addAll(ObjectVector newVector) {

		if (this.size + newVector.size >= this.maxSize) {
			this.maxSize = this.size + newVector.size; // assume no more elements will be added
			System.arraycopy(this.elements, 0, (this.elements = new Object[this.maxSize]), 0, this.size);
		}
		System.arraycopy(newVector.elements, 0, this.elements, this.size, newVector.size);
		this.size += newVector.size;
	}

	
Identity check
/**
	 * Identity check
	 */
	public boolean containsIdentical(Object element) {

		for (int i = this.size; --i >= 0;)
			if (element == this.elements[i])
				return true;
		return false;
	}

	
Equality check
/**
	 * Equality check
	 */
	public boolean contains(Object element) {

		for (int i = this.size; --i >= 0;)
			if (element.equals(this.elements[i]))
				return true;
		return false;
	}

	public void copyInto(Object[] targetArray){

		this.copyInto(targetArray, 0);
	}

	public void copyInto(Object[] targetArray, int index){

		System.arraycopy(this.elements, 0, targetArray, index, this.size);
	}

	public Object elementAt(int index) {

		return this.elements[index];
	}

	public Object find(Object element) {

		for (int i = this.size; --i >= 0;)
			if (element.equals(this.elements[i]))
				return this.elements[i];
		return null;
	}

	public Object remove(Object element) {

		// assumes only one occurrence of the element exists
		for (int i = this.size; --i >= 0;)
			if (element.equals(this.elements[i])) {
				// shift the remaining elements down one spot
				System.arraycopy(this.elements, i + 1, this.elements, i, --this.size - i);
				this.elements[this.size] = null;
				return element;
			}
		return null;
	}

	public void removeAll() {

		for (int i = this.size; --i >= 0;)
			this.elements[i] = null;
		this.size = 0;
	}

	public int size(){

		return this.size;
	}

	@Override
	public String toString() {

		String s = ""; //$NON-NLS-1$
		for (int i = 0; i < this.size; i++)
			s += this.elements[i].toString() + "\n"; //$NON-NLS-1$
		return s;
	}

	@Override
	public Iterator<Object> iterator() {
		return new Iterator<Object>() {
			int i=0;
			@Override
			public boolean hasNext() {
				return this.i < ObjectVector.this.size;
			}
			@Override
			public Object next() {
				return ObjectVector.this.elementAt(this.i++);
			}
		};
	}
}