Utils.java

package org.codehaus.mojo.webstart;

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * 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
 * under the License.
 */

import org.apache.maven.plugin.MojoExecutionException;

import java.io.File;

/**
 * 
 * Some FileUtil methods
 * @todo check if this can be replaced with org.codehaus.plexus.util.FileUtils
 *
 */
class Utils
{
    /**
     * Delete a directory
     *
     * @param d the directory to delete
     */
    public static void removeDir( File d )
        throws MojoExecutionException
    {
        String[] list = d.list();
        if ( list == null )
        {
            list = new String[0];
        }
        for ( int i = 0; i < list.length; i++ )
        {
            String s = list[i];
            File f = new File( d, s );
            if ( f.isDirectory() )
            {
                removeDir( f );
            }
            else
            {
                if ( !delete( f ) )
                {
                    String message = "Unable to delete file " + f.getAbsolutePath();
                    throw new MojoExecutionException( message );
                }
            }
        }
    
        if ( !delete( d ) )
        {
            String message = "Unable to delete directory " + d.getAbsolutePath();
            throw new MojoExecutionException( message );
        }
    }    
    
    /**
     * Accommodate Windows bug encountered in both Sun and IBM JDKs.
     * Others possible. If the delete does not work, call System.gc(),
     * wait a little and try again.
     */
    public static boolean delete( File f )
    {
        if ( !f.delete() )
        {
            if ( System.getProperty( "os.name" ).toLowerCase().indexOf( "windows" ) > -1 )
            {
                System.gc();
            }
            try
            {
                Thread.sleep( 10 );
                return f.delete();
            }
            catch ( InterruptedException ex )
            {
                return f.delete();
            }
        }
        return true;
    }
}