Ptidej-v5.2-master/PADL Creator JavaFile (Eclipse) Tests/data/argouml/trunk/src_new/org/argouml/pattern/cognitive/critics/CrConsiderSingleton.java
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package org.argouml.pattern.cognitive.critics;

import java.util.Iterator;

import org.argouml.cognitive.Designer;
import org.argouml.cognitive.ToDoItem;
import org.argouml.model.Model;
import org.argouml.uml.cognitive.UMLDecision;
import org.argouml.uml.cognitive.critics.CrUML;

/**
 * A critic to detect when a class can never have more than one instance (of
 * itself of any subclasses), and thus whether it is suitable for declaration
 * as a Singleton (with stereotype &laquo;Singleton&raquo;.<p>
 *
 * @see <a
 * href="http://argouml.tigris.org/documentation/snapshots/manual/argouml.html/#s2.ref.critics_singleton_violated">
 * ArgoUML User Manual: Singleton Violated</a>
 *
 * @author jrobbins
 */
public class CrConsiderSingleton extends CrUML {

    /**
     * Constructor for the critic.<p>
     *
     * Sets up the resource name, which will allow headline and description
     * to be found for the current locale. Provides a design issue category
     * (PATTERNS), sets a priority for any to-do items (LOW) and adds triggers
     * for metaclasses "stereotype", "structuralFeature" and
     * "associationEnd".
     */
    public CrConsiderSingleton() {
        setupHeadAndDesc();
        addSupportedDecision(UMLDecision.PATTERNS);
        setPriority(ToDoItem.LOW_PRIORITY);

        // These may not actually make any difference at present (the code
        // behind addTrigger needs more work).

        addTrigger("stereotype");
        addTrigger("structuralFeature");
        addTrigger("associationEnd");
    }


    /**
     * The trigger for the critic.<p>
     *
     * First check we are already a Singleton.<p>
     *
     * Otherwise plausible candidates for the Singleton design pattern are
     * classes with no instance variables (i.e. non-static attributes) and no
     * outgoing associations.<p>
     *
     * @param  dm    the {@link java.lang.Object Object} to be checked against
     *               the critic.
     *
     * @param  dsgr  the {@link org.argouml.cognitive.Designer Designer}
     *               creating the model. Not used, this is for future
     *               development of ArgoUML.
     *
     * @return       {@link #PROBLEM_FOUND PROBLEM_FOUND} if the critic is
     *               triggered, otherwise {@link #NO_PROBLEM NO_PROBLEM}.
     */

    public boolean predicate2(Object dm, Designer dsgr) {

        // Only look at classes...

        if (!(Model.getFacade().isAClass(dm))) {
            return NO_PROBLEM;
        }

        // and not association classes
        if (Model.getFacade().isAAssociationClass(dm)) {
            return NO_PROBLEM;
        }

        // with a name...
        if (Model.getFacade().getName(dm) == null
                || "".equals(Model.getFacade().getName(dm))) {
            return NO_PROBLEM;
        }

        // ... and not incompletely imported
        if (!(Model.getFacade().isPrimaryObject(dm))) {
            return NO_PROBLEM;
        }

        	// abstract classes are hardly ever singletons
        if (Model.getFacade().isAbstract(dm)) {
            return NO_PROBLEM;
        }

        // Check for Singleton stereotype, uninitialised instance variables and
        // outgoing associations, as per JavaDoc above.

        if (Model.getFacade().isSingleton(dm)) {
            return NO_PROBLEM;
        }

	if (Model.getFacade().isUtility(dm)) {
	    return NO_PROBLEM;
	}

	// If there is an attribute with instance scope => no problem
	Iterator iter = Model.getFacade().getAttributes(dm).iterator();

	while (iter.hasNext()) {
	    if (Model.getFacade().isInstanceScope(iter.next())) {
	        return NO_PROBLEM;
	    }
	}


	// If there is an outgoing association => no problem
	Iterator ends = Model.getFacade().getAssociationEnds(dm).iterator();

	while (ends.hasNext()) {
	    Iterator otherends =
		Model.getFacade()
			.getOtherAssociationEnds(ends.next()).iterator();

	    while (otherends.hasNext()) {
		if (Model.getFacade().isNavigable(otherends.next())) {
		    return NO_PROBLEM;
		}
	    }
	}

	return PROBLEM_FOUND;
    }


    /**
     * The UID.
     */
    private static final long serialVersionUID = -178026888698499288L;
} /* end class CrConsiderSingleton */

