file_persistent_stream_repository.java

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/***********************************************************************
 * Copyright (c) 2000-2004 The Apache Software Foundation.             *
 * All rights reserved.                                                *
 * ------------------------------------------------------------------- *
 * 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.                      *
 ***********************************************************************/

package org.apache.james.mailrepository.filepair;

import java.io.BufferedOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.ArrayList;
import java.util.HashMap;
import org.apache.avalon.cornerstone.services.store.StreamRepository;
import org.apache.avalon.excalibur.io.IOUtil;

/**
 * Implementation of a StreamRepository to a File.
 * TODO: -retieve(String key) should return a FilterInputStream to allow
 * mark and reset methods. (working not like BufferedInputStream!!!)
 *
 */
public class File_Persistent_Stream_Repository
    extends AbstractFileRepository
    implements StreamRepository
{
    protected final HashMap m_inputs = new HashMap();
    protected final HashMap m_outputs = new HashMap();

    protected String getExtensionDecorator()
    {
        return ".FileStreamStore";
    }

    /**
     * Get the object associated to the given unique key.
     */
    public synchronized InputStream get( final String key )
    {
        try
        {
            final ResettableFileInputStream stream =
                new ResettableFileInputStream( getFile( key ) );

            final Object o = m_inputs.get( key );
            if( null == o )
            {
                m_inputs.put( key, stream );
            }
            else if( o instanceof ArrayList )
            {
                ( (ArrayList)o ).add( stream );
            }
            else
            {
                final ArrayList list = new ArrayList();
                list.add( o );
                list.add( stream );
                m_inputs.put( key, list );
            }

            return stream;
        }
        catch( final IOException ioe )
        {
            final String message = "Exception caught while retrieving a stream ";
            getLogger().warn( message, ioe );
            throw new RuntimeException( message + ": " + ioe );
        }
    }

    /**
     * Store the given object and associates it to the given key
     */
    public synchronized OutputStream put( final String key )
    {
        try
        {
            final OutputStream outputStream = getOutputStream( key );
            final BufferedOutputStream stream = new BufferedOutputStream( outputStream );

            final Object o = m_outputs.get( key );
            if( null == o )
            {
                m_outputs.put( key, stream );
            }
            else if( o instanceof ArrayList )
            {
                ( (ArrayList)o ).add( stream );
            }
            else
            {
                final ArrayList list = new ArrayList();
                list.add( o );
                list.add( stream );
                m_outputs.put( key, list );
            }

            return stream;
        }
        catch( final IOException ioe )
        {
            final String message = "Exception caught while storing a stream ";
            getLogger().warn( message, ioe );
            throw new RuntimeException( message + ": " + ioe );
        }
    }

    public synchronized void remove( final String key )
    {
        Object o = m_inputs.remove( key );
        if( null != o )
        {
            if( o instanceof InputStream )
            {
                IOUtil.shutdownStream( (InputStream)o );
            }
            else
            {
                final ArrayList list = (ArrayList)o;
                final int size = list.size();

                for( int i = 0; i < size; i++ )
                {
                    IOUtil.shutdownStream( (InputStream)list.get( i ) );
                }
            }
        }

        o = m_outputs.remove( key );
        if( null != o )
        {
            if( o instanceof OutputStream )
            {
                IOUtil.shutdownStream( (OutputStream)o );
            }
            else
            {
                final ArrayList list = (ArrayList)o;
                final int size = list.size();

                for( int i = 0; i < size; i++ )
                {
                    IOUtil.shutdownStream( (OutputStream)list.get( 0 ) );
                }
            }
        }

        super.remove( key );
    }

    public long getSize(final String key) {
        try {
            return getFile(key).length();
        }
        catch(IOException e) {
            return 0;
        }
    }
}