TypeList.java

/* Software Name : AsmDex
 * Version : 1.0
 *
 * Copyright © 2012 France Télécom
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the copyright holders nor the names of its
 *    contributors may be used to endorse or promote products derived from
 *    this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
 * THE POSSIBILITY OF SUCH DAMAGE.
 */

package org.ow2.asmdex.structureWriter;

import java.util.Arrays;

/**
 * Class representing the type_list structure of the Dex file. Consists in a list of type_ids, which are
 * here represented as simple Strings.
 * 
 * @author Julien Névo.
 *
 */
public class TypeList implements Comparable<TypeList> {

	/**
	 * Types of the TypeList.
	 */
	final private String[] types;
	
	/**
	 * The hashCode of the TypeList.
	 */
	final private int hashCode;
	
	/**
	 * Constructor of a TypeList.
	 * @param types types to add to the TypeList. May be Null.
	 */
	public TypeList(String[] types) {
		if (types != null) {
			this.types = types;
			
			// Calculates the HashCode.
			int result = 0;
			for (String string : types) {
				result += string.hashCode();
			}
			
			hashCode = result;
		} else {
			hashCode = 0;
			this.types = new String[0];
		}
	}
	

	// -------------------------------------
	// Getters.
	// -------------------------------------
	
	/**
	 * Gives back the list of types 
	 * @return types formatted in Java format
	 */
	public String[] getTypeList() {
		return types;
	}
	
	/**
	 * Number of types in the list
	 * @return number of types.
	 */
	public int size() {
		return types.length;
	}
	
	/**
	 * Get a type from the list
	 * @param index position of the type
	 * @return the type as a string in Java format
	 */
	public String get(int index) {
		return types[index];
	}
	

	// ----------------------------------------------
	// Overridden methods.
	// ----------------------------------------------
	
	@Override
	public boolean equals(Object o) {
		if (this == o) {
			return true;
		}

		if (o instanceof TypeList) {
			TypeList secondTypeList = (TypeList)o;
			return Arrays.deepEquals(types, secondTypeList.types);
		}
		
		return false;
	}
	
	@Override
	public int hashCode() {
		return hashCode;
	}
	
	@Override
	public int compareTo(TypeList o) {
		if (this == o) {
			return 0;
		}
		
		String[] secondTypes = o.getTypeList();
		
		// We compare the Strings one by one.
		int sizeFirstArray = types.length;
		int sizeSecondArray = secondTypes.length;
		int minSize = sizeFirstArray < sizeSecondArray ? sizeFirstArray : sizeSecondArray;
		for (int i = 0; i < minSize; i++) {
			int compare = types[i].compareTo(secondTypes[i]); 
			if (compare != 0) {
				return compare;
			}
		}
		
		// Compares the size.
		return (sizeFirstArray == sizeSecondArray ? 0 : (sizeFirstArray < sizeSecondArray ? -1 : 1));
	}
}