package org.codehaus.plexus.util.dag;

/*
 * Copyright The Codehaus Foundation.
 *
 * Licensed 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 under the License.
 */

import java.util.Iterator;
import java.util.List;

public class CycleDetectedException
    extends Exception
{
    private List<String> cycle;

    public CycleDetectedException( final String message, final List<String> cycle )
    {
        super( message );

        this.cycle = cycle;

    }

    public List<String> getCycle()
    {
        return cycle;
    }

    /**
     * @return
     */
    public String cycleToString()
    {
        final StringBuilder buffer = new StringBuilder();

        for ( Iterator<String> iterator = cycle.iterator(); iterator.hasNext(); )
        {
            buffer.append( iterator.next() );

            if ( iterator.hasNext() )
            {
                buffer.append( " --> " );
            }
        }
        return buffer.toString();
    }

    public String getMessage()
    {
        return super.getMessage() + " " + cycleToString();
    }
}
