Answer.java

/***
 * Copyright (c) 2008, Endless Loop Software, Inc.
 * 
 * This file is part of EgoNet.
 * 
 * EgoNet is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 3 of the License, or
 * (at your option) any later version.
 * 
 * EgoNet is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
package org.egonet.model.answer;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Date;
import java.util.List;
import java.util.Random;
import java.text.*;

import org.egonet.exceptions.MalformedQuestionException;

public abstract class Answer implements Cloneable {
    /**
     * Unique ID for every question
     */
    private Long questionId;

    public Long getQuestionId() {
		return questionId;
	}

	public void setQuestionId(Long questionId) {
		this.questionId = questionId;
	}

	/**
     * Represents the alter or alter pair that this answer is about. It may be a
     * single alter for alter questions, or two alters for an alter pair
     * question.
     */
    private List<Integer> alters;

    public void setAlters(List<Integer> alters) {
		this.alters = alters;
	}
    
    public void setAlters(int [] alters) {
		this.alters = new ArrayList<Integer>();
		for(int i : alters) this.alters.add(i);
	}

	private boolean _answered = false;

    public boolean isAnswered() {
		return _answered;
	}

	public void setAnswered(boolean _answered) {
		this._answered = _answered;
	}

	public boolean adjacent;

    private int value;

    private int index;

    public String string;

    public String timestamp;

    public static final int NO_ANSWER = -1;
    public static final int ALL_ADJACENT = -2;

    private static Random generator = new Random(System.currentTimeMillis());
    
    public Answer() {
    	this((long)generator.nextInt());
    }
    
    public Answer(Long Id) {
        this(Id, null);
    }

    public Answer(Long Id, int[] alters) {
        //logger.info("New answer object created with id="+Id+" and alters: " + Arrays.asList(alters));
        questionId = Id;
        setAnswered(false);
        adjacent = false;
        setValue(-1);
        string = "";
        timestamp = DateFormat.getDateInstance().format(new Date());

        if (alters == null) {
            this.alters = new ArrayList<Integer>();
        } else {
            this.alters = new ArrayList<Integer>(alters.length);
            for(Integer a : alters)
                this.alters.add(a);
        }
    }
    
    public Integer firstAlter()
    {
        return alters.get(0);
    }
    
    public Integer secondAlter()
    {
        return alters.get(1);
    }

    public boolean hasTwoAlters()
    {
        return alters.size() > 1;
    }
    
    public boolean hasAtLeastOneAlter()
    {
        return alters.size() > 0;
    }
    
    public Object clone() throws CloneNotSupportedException {
        return (super.clone());
    }

    public String toString() {
    	return string == null ? getValue()+"" : string;
    }

    public String getString() {
        String str = "";
        str = "questionId=" + questionId + ", answered=" + isAnswered() + ", adjacent=" + adjacent +  ", string=" + string + ", index="+getIndex()+", value=" + getValue();
        return str;

    }

    public void setValue(int value) {
        this.value = value;
    }

    public int getValue() {
        return value;
    }

    public void setIndex(int index) {
        this.index = index;
    }

    public int getIndex() {
        return index;
    }

    public List<Integer> getAlters() {
        return Collections.unmodifiableList(alters);
    }
    
	/**
	 * Given a string representation of a question subclass, return the class object. This is mostly used when unserializing textual representations of subclasses.
	 * 
	 * @param questionType type of question subclass
	 * @return a class object representing that type
	 */
	
	public static Class<? extends Answer> asSubclass(String answerType) {
		try {
			@SuppressWarnings("unchecked")
			Class<? extends Answer> clazz = (Class<? extends Answer>)Class.forName(answerType);

			return clazz;
		} 
		catch (Exception ex) {
			throw new RuntimeException(ex);
		}
	}
	
	public static Answer newInstance(String answerType) {
		try {
			Class<? extends Answer> clazz = asSubclass(answerType);

			return newInstance(clazz);
		} 
		catch (Exception ex) {
			throw new MalformedQuestionException(ex);
		}
	}
	
	public static Answer newInstance(Class<? extends Answer> clazz) {
		try {
			return clazz.newInstance();
		} 
		catch (Exception ex) {
			throw new MalformedQuestionException("could not instantiate an instance of class " + clazz.getCanonicalName(),ex);
		}
	}
}