wagon-provider-api/src/main/java/org/apache/maven/wagon/StreamWagon.java

package org.apache.maven.wagon;

/* ====================================================================
 *   Copyright 2001-2004 The Apache Software 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 org.apache.maven.wagon.authentication.AuthenticationException;
import org.apache.maven.wagon.authorization.AuthorizationException;
import org.apache.maven.wagon.resource.Resource;

import java.io.*;


/**
 * Base class for wagon which provide stream based API.
 * 
 * @author <a href="mailto:michal@codehaus.org">Michal Maczka</a>
 * @version $Id$
 */
public abstract class StreamWagon
    extends AbstractWagon
{

    // ----------------------------------------------------------------------
    //
    // ----------------------------------------------------------------------

    public abstract void fillInputData( InputData inputData )
        throws TransferFailedException, ResourceDoesNotExistException;

    public abstract void fillOutputData( OutputData outputData )
        throws TransferFailedException;

    public abstract void openConnection()
        throws ConnectionException, AuthenticationException;

    public abstract void closeConnection()
        throws ConnectionException;

    // ----------------------------------------------------------------------
    //
    // ----------------------------------------------------------------------

    public void get( String resourceName, File destination )
        throws TransferFailedException, ResourceDoesNotExistException, AuthorizationException
    {
        InputData inputData = new InputData( );

        Resource resource = new Resource( resourceName );

        inputData.setResource( resource );

        fillInputData( inputData );

        InputStream is = inputData.getInputStream();

        if ( is == null )
        {
            throw new TransferFailedException( getRepository().getUrl() + " - Could not open input stream for resource: '" + resource+ "'" );
        }

        createParentDirectories( destination );

        getTransfer( inputData.getResource(), destination, is );
    }

    public boolean getIfNewer( String resourceName, File destination, long timestamp)
            throws TransferFailedException, ResourceDoesNotExistException, AuthorizationException
    {
        boolean retValue = false;

        InputData inputData = new InputData( );

        Resource resource = new Resource( resourceName );

        inputData.setResource( resource );

        fillInputData( inputData );

        InputStream is = inputData.getInputStream();

        if ( resource.getLastModified() > timestamp )
        {
            retValue = true;

            if ( is == null )
            {
                throw new TransferFailedException( getRepository().getUrl() + " - Could not open input stream for resource: '" + resource+ "'" );
            }

            createParentDirectories( destination );

            getTransfer( inputData.getResource(), destination, is );
        }
        else
        {
            shutdownStream( is );
        }

        return retValue;
    }


    // source doesn't exist exception
    public void put( File source, String resourceName )
        throws TransferFailedException, ResourceDoesNotExistException, AuthorizationException
    {
        OutputData outputData = new OutputData( );

        Resource resource = new Resource( resourceName );

        outputData.setResource( resource );

        fillOutputData( outputData );

        OutputStream os = outputData.getOutputStream( );

        if ( os == null )
        {
            throw new TransferFailedException( getRepository().getUrl() + " - Could not open output stream for resource: '" + resource+ "'" );
        }

        putTransfer( outputData.getResource(), source, os, true );
    }
}