choice.java

java案例开发一书的源代码

/*
 * ChoiceItem.java
 *
 * Created on 2003年11月5日, 下午9:13
 */

package romulus;

/**
 *
 * @author  Romulus
 * @version 1.0
 */
public class Choice implements QuestionItem {
    
    /** The ident of the choice.*/
    private String ident = null;
    
    /** The number of correct answer.*/
    private int rcardinality = 1;
    
    /** True if the chlice item should be shuffled.*/
    private boolean shuffle = false;
    
    /** The answer of the choice.
     * It is the Vector of ChoiceItem selected.
     */
    private java.util.Vector answer = new java.util.Vector();
    
    /** The choice items.*/
    private java.util.List citems ;
    
    /** The content of the question item.*/
    private Content cont = null;
    
    /** Creates a new instance of ChoiceItem */
    public Choice(String ident, int rca, boolean shu) throws RomulusException{
        if(ident == null){
            throw new RomulusException(RomulusException.IdentError);
        }
        this.ident = ident;
        this.rcardinality = rca;
        this.shuffle = shu;
        if(shu){
            citems = new RandomList();
        }
        else{
            citems = new java.util.Vector();
        }
    }
    
    /** Add and remove the choiceitem.*/
    void addChoiceItem(ChoiceItem ci){
        this.citems.add(ci);
    }
    
    boolean removeChoiceItem(ChoiceItem ci){
        return this.citems.remove(ci);
    }
    
    public java.util.Iterator choiceitemIterator(){
        return citems.iterator();
    }

    /** Add and remove the answer.*/
    public void addAnswer(ChoiceItem ci){
        this.answer.add(ci);
    }
    
    public void clearAnswer(){
        this.answer.clear();
    }
    
    public boolean removeAnswer(ChoiceItem ci){
        return this.answer.remove(ci);
    }
    
    public java.util.Iterator answerIterator(){
        return answer.iterator();
    }
    
    public java.util.AbstractList answerList(){
        return answer;
    }

    /**
     * Such method is used to check the correct of the question item.
     */
    public boolean isCorrect() {
        java.util.Iterator ite = citems.iterator();
        ChoiceItem citem = null;
        java.util.Vector canswer = new java.util.Vector();
        //get all of the correct answer
        while(ite.hasNext()){
            citem = (ChoiceItem)ite.next();
            if(citem.isCorrect()){
                canswer.add(citem);
            }
        }
        //check all the correct answers are selected and all the selected answer is correct.
        return canswer.containsAll(answer)&&answer.containsAll(canswer);
    }
    
    public Content getContent(){
        return this.cont;
    }
    
    void setContent(Content c){
        this.cont = c;
    }
    
    /** get information*/
    public String getIdent(){
        return this.ident;
    }
    
    public int getRcardinality(){
        return this.rcardinality;
    }
    
    public boolean isShuffle(){
        return this.shuffle;
    }

    
    /** The method used to accept the Visitor to do something. */
    public void Accept(Visitor v) throws java.sql.SQLException, RomulusException{
        v.VisitQuestionItem(this);
    }
    
}