Answer.java

/*******************************************************************************
 * Copyright 2012 UPM, http://www.upm.es 
 Universidad Politécnica de Madrid
 * 
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 *   http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 ******************************************************************************/
package org.universAAL.ontology.questionnaire;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.HashSet;
import java.util.List;
import java.util.Set;

import org.universAAL.middleware.owl.ManagedIndividual;

/**
 * This class describes the concept of Answer, its properties and its associated
 * methods.
 * 
 * @author mdelafuente
 * 
 */
public class Answer extends ManagedIndividual {

    // NAMESPACE & PROPERTIES

    public static final String MY_URI = QuestionnaireOntology.NAMESPACE
	    + "Answer";
    public static final String PROP_ANSWER_CONTENT = QuestionnaireOntology.NAMESPACE
	    + "answerContent";
    public static final String PROP_IS_ASSOCIATED_TO_A_QUESTION = QuestionnaireOntology.NAMESPACE
	    + "isAssociatedToAQuestion";

    public static final int CORRECT_ANSWER = 0;
    public static final int INCORRECT_ANSWER = 1;
    public static final int NO_CORRECT_ANSWER = 2;

    // CONSTRUCTORS
    public Answer() {
	super();
    }

    public Answer(String uri) {
	super(uri);
    }

    public Answer(Object content, Question associatedQuestion) {
	this.addAnswerContent(content);
	this.setAssociatedQuestion(associatedQuestion);
    }

    public Answer(Object[] content, Question associatedQuestion) {
	this.setAnswerContent(content);
	this.setAssociatedQuestion(associatedQuestion);
    }

    public String getClassURI() {
	return MY_URI;
    }

    public int getPropSerializationType(String arg0) {
	return PROP_SERIALIZATION_FULL;
    }

    public boolean isWellFormed() {
	return true && props.containsKey(PROP_ANSWER_CONTENT)
		&& props.containsKey(PROP_IS_ASSOCIATED_TO_A_QUESTION);
    }

    // GETTERS AND SETTERS

    /**
     * The following method gets the associated question to an answer. The name
     * automatically-generated by the modeling tool has been changed to be
     * clearer, from "getIsAssociatedToAQuestion" to "getAssociatedQuestion"
     * 
     * @return the associated question
     * @see Question
     */
    public Question getAssociatedQuestion() {
	return (Question) props.get(PROP_IS_ASSOCIATED_TO_A_QUESTION);
    }

    /**
     * The following method sets the associated question to an answer. The name
     * automatically-generated by the modeling tool has been changed to be
     * clearer, from "setIsAssociatedToAQuestion" to "setAssociatedQuestion"
     * 
     * @param the
     *            associated question
     * @see Question
     */
    public void setAssociatedQuestion(Question question) {
	if (question != null)
	    props.put(PROP_IS_ASSOCIATED_TO_A_QUESTION, question);
    }

    /**
     * The following method gets the content of an answer. This content can
     * consist in one resource or more.
     * 
     * @return the answer's content ({@link Object})
     */

    public Object[] getAnswerContent() {

	Object propList = props.get(PROP_ANSWER_CONTENT);
	if (propList instanceof List) {
	    return (Object[]) ((List) propList).toArray(new Object[0]);
	} else {
	    List returnList = new ArrayList();
	    if (propList != null)
		returnList.add((Object) propList);
	    return (Object[]) returnList.toArray(new Object[0]);
	}
    }

    /**
     * The following method sets the content of an answer, when the answer
     * consists of one resource.
     * 
     * @param the
     *            answer's content ({@link Object})
     */

    public void addAnswerContent(Object content) {
	if (content != null)
	    props.put(PROP_ANSWER_CONTENT, content);
    }

    /**
     * The following method sets the content of an answer when the answer
     * consists of more than one resource, such as in multi-choice questions.
     * 
     * @param the
     *            answer's content ({@link Object})
     */

    public void setAnswerContent(Object[] content) {
	List propList = new ArrayList(content.length);
	for (int i = 0; i < content.length; i++) {
	    propList.add(content[i]);
	}
	props.put(PROP_ANSWER_CONTENT, propList);
    }

    // OTHER METHODS
    /**
     * The following method checks if an answer is correct by comparing it with
     * the correct answer expected.
     * 
     * @return true if the question is correct
     * @return false if the question is NOT correct
     * @return null if the question is has not correct-answer associated
     */

    /*
     * public Boolean isCorrectAnswer(){
     * 
     * Question associatedQuestion = getAssociatedQuestion();
     * 
     * if(!associatedQuestion.isHasCorrectAnswer()) //if the question has no
     * correct answer return null;
     * 
     * Object[] correctAnswers = associatedQuestion.getCorrectAnswers();
     * Object[] answerContent = getAnswerContent(); Set <Object>
     * correctAnswersSet = new HashSet <Object> (Arrays.asList(correctAnswers));
     * Set <Object> answerContentSet = new HashSet <Object>
     * (Arrays.asList(answerContent));
     * 
     * 
     * boolean condition = answerContentSet.containsAll(correctAnswersSet) &&
     * correctAnswersSet.containsAll(answerContentSet); return condition; }
     */

    public int isCorrectAnswer() {

	Question associatedQuestion = getAssociatedQuestion();

	if (!associatedQuestion.isHasCorrectAnswer()) // if the question has no
	    // correct answer
	    return NO_CORRECT_ANSWER;

	Object[] correctAnswers = associatedQuestion.getCorrectAnswers();
	Object[] answerContent = getAnswerContent();
	Set correctAnswersSet = new HashSet(Arrays.asList(correctAnswers));
	Set answerContentSet = new HashSet(Arrays.asList(answerContent));

	boolean condition = answerContentSet.containsAll(correctAnswersSet)
		&& correctAnswersSet.containsAll(answerContentSet);
	if (condition == true)
	    return CORRECT_ANSWER;
	else
	    return INCORRECT_ANSWER;
    }
}