BasicExpressionTreeNode.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.mappingsplugin.ui.query.relational;

import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;

import javax.swing.tree.DefaultTreeModel;

import org.eclipse.persistence.tools.workbench.mappingsmodel.query.relational.MWArgument;
import org.eclipse.persistence.tools.workbench.mappingsmodel.query.relational.MWBasicExpression;
import org.eclipse.persistence.tools.workbench.mappingsmodel.query.relational.MWLiteralArgument;
import org.eclipse.persistence.tools.workbench.mappingsmodel.query.relational.MWQueryParameterArgument;
import org.eclipse.persistence.tools.workbench.mappingsmodel.query.relational.MWQueryableArgument;



/**
 * Node for a BasicExpression in an Expression tree
 * The display in the tree will be   firstArgument operator secondArgument
 * BasicExpressionTreeNodes never have children and their parent is always a CompoundExpressionTreeNode
 */
final class BasicExpressionTreeNode extends ExpressionTreeNode implements PropertyChangeListener
{

    BasicExpressionTreeNode(MWBasicExpression basicExpression)
    {
        this(basicExpression, null);
    }

    BasicExpressionTreeNode(MWBasicExpression basicExpression, DefaultTreeModel model)
    {
        super(basicExpression, false, model); //these nodes can never have children
    }

    MWBasicExpression getBasicExpression()
    {
        return (MWBasicExpression) getUserObject();
    }

    public void initializeChildren()
    {
        //BasicExpressions do not have children, so do nothing here
    }

    protected void engageListeners()
    {
         getBasicExpression().addPropertyChangeListener(this);
         getBasicExpression().getFirstArgument().addPropertyChangeListener(this);

         if (getBasicExpression().getSecondArgument() != null)
              getBasicExpression().getSecondArgument().addPropertyChangeListener(this);
     }

    protected void disengageListeners()
    {
        getBasicExpression().removePropertyChangeListener(this);
         getBasicExpression().getFirstArgument().removePropertyChangeListener(this);

         if (getBasicExpression().getSecondArgument() != null)
              getBasicExpression().getSecondArgument().removePropertyChangeListener(this);
     }

    public void propertyChange(PropertyChangeEvent evt)
    {
        String propertyName = evt.getPropertyName();
        if ( propertyName == MWBasicExpression.OPERATOR_TYPE_PROPERTY
            || propertyName == MWQueryableArgument.QUERYABLE_ARGUMENT_ELEMENT_PROPERTY
            || propertyName == MWLiteralArgument.VALUE_PROPERTY
            || propertyName == MWQueryParameterArgument.QUERY_PARAMETER_PROPERTY)
            {
                getModel().nodeChanged(this);
            }
        else if (propertyName == MWBasicExpression.FIRST_ARUGMENT_PROPERTY
            || propertyName == MWBasicExpression.SECOND_ARGUMENT_PROPERTY)
            {
                MWArgument oldArgument = (MWArgument)evt.getOldValue();
                MWArgument newArgument = (MWArgument)evt.getNewValue();
                if (oldArgument != null)
                    oldArgument.removePropertyChangeListener(this);
                if (newArgument != null)
                    newArgument.addPropertyChangeListener(this);

                getModel().nodeChanged(this);
            }
    }
}