DefaultStaticResource.java

/**
 * Copyright (c) 2008-2011 Sonatype, Inc.
 * All rights reserved. Includes the third-party code listed at http://www.sonatype.com/products/nexus/attributions.
 *
 * This program is free software: you can redistribute it and/or modify it only under the terms of the GNU Affero General
 * Public License Version 3 as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied
 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Affero General Public License Version 3
 * for more details.
 *
 * You should have received a copy of the GNU Affero General Public License Version 3 along with this program.  If not, see
 * http://www.gnu.org/licenses.
 *
 * Sonatype Nexus (TM) Open Source Version is available from Sonatype, Inc. Sonatype and Sonatype Nexus are trademarks of
 * Sonatype, Inc. Apache Maven is a trademark of the Apache Foundation. M2Eclipse is a trademark of the Eclipse Foundation.
 * All other trademarks are the property of their respective owners.
 */
package org.sonatype.nexus.plugins.rest;

import java.io.IOException;
import java.io.InputStream;
import java.net.URL;
import java.net.URLConnection;

public class DefaultStaticResource
    implements StaticResource
{
    private final URL resourceURL;

    private final String path;

    private volatile URLConnection urlConnection;
    
    private String contentType;
    
    public DefaultStaticResource( URL url, String path, String contentType )
    {
        this.resourceURL = url;

        this.path = path;
        
        this.contentType = contentType;
    }

    protected synchronized boolean checkConnection()
    {
        if ( urlConnection == null )
        {
            try
            {
                urlConnection = resourceURL.openConnection();
            }
            catch ( IOException e )
            {
                // ignore it?
                urlConnection = null;
            }
        }

        return urlConnection != null;
    }

    public String getPath()
    {
        if ( path != null )
        {
            return path;
        }
        else
        {
            return resourceURL.getPath();
        }
    }

    public long getSize()
    {
        if ( checkConnection() )
        {
            return urlConnection.getContentLength();
        }
        else
        {
            return -1;
        }
    }

    public String getContentType()
    {
        if ( contentType != null )
        {
            return contentType;
        }
        else if ( checkConnection() )
        {
            return urlConnection.getContentType();
        }
        else
        {
            return null;
        }
    }

    public InputStream getInputStream()
        throws IOException
    {
        if ( checkConnection() )
        {
            InputStream is = urlConnection.getInputStream();

            urlConnection = null;

            return is;
        }
        else
        {
            throw new IOException( "Invalid resource!" );
        }
    }

    public Long getLastModified()
    {
        if ( checkConnection() )
        {
            return urlConnection.getLastModified();
        }
        return null;
    }

    @Override
    public String toString()
    {
        StringBuilder builder = new StringBuilder();
        builder.append( "DefaultStaticResource [" );
        if ( path != null )
        {
            builder.append( "path=" );
            builder.append( path );
            builder.append( ", " );
        }
        if ( contentType != null )
        {
            builder.append( "contentType=" );
            builder.append( contentType );
        }
        builder.append( "]" );
        return builder.toString();
    }

}