MenuItemComparatorByHierarchy.java

/*
 * Copyright 2000-2013 Enonic AS
 * http://www.enonic.com/license
 */
package com.enonic.cms.core.structure.menuitem;

import java.io.Serializable;
import java.util.Comparator;

public class MenuItemComparatorByHierarchy
    implements Comparator<MenuItemEntity>, Serializable
{
    private static final long serialVersionUID = -6540903107046469057L;

    public int compare( final MenuItemEntity a, final MenuItemEntity b )
    {
        if (a == b) {
            return 0;
        }

        // return -1 if a is before than b
        // return 0 if a has equal order to b
        // return +1 if a is after b

        final int levelOfA = a.getLevel();
        final int levelOfB = b.getLevel();
        if ( levelOfA < levelOfB )
        {
            return -1;
        }
        else if ( levelOfA > levelOfB )
        {
            return +1;
        }

        // at this point a and be are at the same level in the menu hierarchy

        final int orderOfA = a.getOrder();
        final int orderOfB = b.getOrder();
        if ( orderOfA < orderOfB )
        {
            return -1;
        }
        else if ( orderOfA > orderOfB )
        {
            return +1;
        }

        // NOTE: This has to be done to prevent trouble with equals when menuItems have same order but different keys
        return ( a.getKey().toInt() < b.getKey().toInt() ? -1 : ( a.getKey().toInt() == b.getKey().toInt() ? 0 : 1 ) );
    }


}