MWOrderingItem.java

/*******************************************************************************
 * Copyright (c) 1998, 2015 Oracle and/or its affiliates. All rights reserved.
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License v1.0 and Eclipse Distribution License v. 1.0
 * which accompanies this distribution.
 * The Eclipse Public License is available at http://www.eclipse.org/legal/epl-v10.html
 * and the Eclipse Distribution License is available at
 * http://www.eclipse.org/org/documents/edl-v10.php.
 *
 * Contributors:
 *     Oracle - initial API and implementation from Oracle TopLink
******************************************************************************/
package org.eclipse.persistence.tools.workbench.mappingsmodel.query.relational;

import java.util.Iterator;

import org.eclipse.persistence.tools.workbench.mappingsmodel.ProblemConstants;
import org.eclipse.persistence.tools.workbench.mappingsmodel.query.MWQueryable;
import org.eclipse.persistence.tools.workbench.utility.node.Node;
import org.eclipse.persistence.tools.workbench.utility.node.Problem;

import org.eclipse.persistence.expressions.Expression;
import org.eclipse.persistence.mappings.foundation.AbstractDirectMapping;
import org.eclipse.persistence.oxm.XMLDescriptor;
import org.eclipse.persistence.queries.ObjectLevelReadQuery;
import org.eclipse.persistence.queries.ReadAllQuery;


public final class MWOrderingItem extends MWAttributeItem implements Ordering {

    private volatile boolean ascending;

    // ******************* Static Methods **************

    public static XMLDescriptor buildDescriptor() {
        XMLDescriptor descriptor = new XMLDescriptor();
        descriptor.setJavaClass(MWOrderingItem.class);

        descriptor.getInheritancePolicy().setParentClass(MWAttributeItem.class);

        ((AbstractDirectMapping) descriptor.addDirectMapping("ascending", "ascending/text()")).setNullValue(Boolean.TRUE);

        return descriptor;
    }


    // ****************** Constructors ************

    /** Default constructor - for TopLink use only*/
    private MWOrderingItem() {
        super();
    }

    MWOrderingItem(MWRelationalReadAllQuery parent, MWQueryable queryable) {
        super(parent, queryable);
    }

    MWOrderingItem(MWRelationalReadAllQuery parent, Iterator queryables) {
        super(parent, queryables);

    }

    MWOrderingItem(MWRelationalReadAllQuery parent, Iterator queryables, Iterator allowsNull) {
        super(parent, queryables, allowsNull);
    }


    /** Initialize persistent state*/
    protected void initialize(Node parentNode) {
        super.initialize(parentNode);

        this.ascending = true;
    }


    // ****************** Accessors ************

    public boolean isAscending() {
        return this.ascending;
    }

    public boolean isDesending() {
        return !isAscending();
    }

    public void setAscending(boolean ascending) {
        boolean old = this.ascending;
        this.ascending = ascending;
        firePropertyChanged(ASCENDING_PROPERTY, old, this.ascending);
    }


    // ****************** MWQueryItem implementation ************

    public void removeSelfFromParent() {
        ((MWRelationalReadAllQuery) getParentQuery()).removeOrderingItem(this);
    }


    // ****************** Problems ************

    public Problem queryableNullProblem() {
        return buildProblem(
                ProblemConstants.QUERYABLE_NULL_FOR_ORDERING_ITEM,
                getParentQuery().signature(),
                new Integer(((MWRelationalReadAllQuery) getParentQuery()).indexOfOrderingItem(this) + 1));
    }

    public Problem queryableInvalidProblem(MWQueryable queryable) {
        return buildProblem(
                        ProblemConstants.QUERYABLE_NOT_VALID_FOR_READ_ALL_QUERY_ORDERING_ITEM,
                        queryable.displayString(),
                        getParentQuery().signature());
    }

    public boolean isQueryableValid(MWQueryable queryable) {
        return queryable.isValidForReadAllQueryOrderable();
    }


    // ****************** Runtime Conversion ************

    protected void adjustRuntimeQuery(ObjectLevelReadQuery readQuery) {
        Expression expression = getQueryableArgument().runtimeExpression(readQuery.getExpressionBuilder());

        if (isAscending()) {
            ((ReadAllQuery) readQuery).addOrdering(expression.ascending());
        }
        else {
            ((ReadAllQuery) readQuery).addOrdering(expression.descending());
        }

    }


    public String displayString() {
        String displayString = super.displayString() + " (";
        if (isAscending()) {
            displayString += "Ascending"; //TODO i18n?
        }
        else {
            displayString += "Descending";
        }
        return displayString + ")";
    }
}