old_trunk/schema-registries/src/main/java/org/apache/directory/server/schema/DnComparator.java

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 *  or more contributor license agreements.  See the NOTICE file
 *  distributed with this work for additional information
 *  regarding copyright ownership.  The ASF licenses this file
 *  to you under the Apache License, Version 2.0 (the
 *  "License"); you may not use this file except in compliance
 *  with the License.  You may obtain a copy of the License at
 *  
 *    http://www.apache.org/licenses/LICENSE-2.0
 *  
 *  Unless required by applicable law or agreed to in writing,
 *  software distributed under the License is distributed on an
 *  "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 *  KIND, either express or implied.  See the License for the
 *  specific language governing permissions and limitations
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package org.apache.directory.server.schema;


import java.util.Comparator;

import javax.naming.Name;
import javax.naming.NamingException;

import org.apache.directory.server.schema.registries.AttributeTypeRegistry;
import org.apache.directory.server.schema.registries.Registries;
import org.apache.directory.shared.ldap.name.LdapDN;


/**
 * 
 * 
 * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
 * @version $Rev$
 */
public class DnComparator implements Comparator
{
    // @TODO you'll need this to fix the way normalization is done
    private AttributeTypeRegistry attrRegistry;
    
    
    public DnComparator( AttributeTypeRegistry attrRegistry )
    {
        this.attrRegistry = attrRegistry;
    }
    
    
    public DnComparator()
    {
    }

    
    public void setRegistries( Registries registries )
    {
        attrRegistry = registries.getAttributeTypeRegistry();
    }
    
    
    public int compare( Object obj0, Object obj1 ) 
    {
        LdapDN dn0 = null;
        LdapDN dn1 = null;
        
        try 
        {
            dn0 = getDn( obj0 );
            dn1 = getDn( obj1 );
        }
        catch ( NamingException e )
        {
            // -- what do we do here ?
            return -1;
        }
        
        return dn0.compareTo( dn1 );
    }


    public LdapDN getDn( Object obj ) throws NamingException
    {
        LdapDN dn = null;
        
        if ( obj instanceof LdapDN )
        {
            dn = (LdapDN)obj;
            
            dn = ( dn.isNormalized() ? dn : LdapDN.normalize( dn, attrRegistry.getNormalizerMapping() ) );
        }
        else if ( obj instanceof Name )
        {
            dn = new LdapDN( ( Name ) obj );
            dn.normalize( attrRegistry.getNormalizerMapping() );
        }
        else if ( obj instanceof String )
        {
            dn = new LdapDN( ( String ) obj );
            dn.normalize( attrRegistry.getNormalizerMapping() );
        }
        else
        {
            throw new IllegalStateException( "I do not know how to handle dn comparisons with objects of class: " 
                + (obj == null ? null : obj.getClass() ) );
        }
        
        return dn;
    }
}