tapestry-framework/src/java/org/apache/tapestry/asset/PrivateAsset.java

// Copyright 2004, 2005 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.

package org.apache.tapestry.asset;

import org.apache.hivemind.ApplicationRuntimeException;
import org.apache.hivemind.Location;
import org.apache.hivemind.Resource;
import org.apache.hivemind.util.Defense;
import org.apache.tapestry.engine.IEngineService;
import org.apache.tapestry.engine.ILink;

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

/**
 * An implementation of {@link org.apache.tapestry.IAsset} for localizable assets within the JVM's
 * classpath.
 * <p>
 * The localization code here is largely cut-and-paste from {@link ContextAsset}.
 * 
 * @author Howard Ship
 */

public class PrivateAsset extends AbstractAsset
{
    private IEngineService _assetService;

    /**
     * @deprecated To be removed (someday). Use
     *             {@link #PrivateAsset(Resource, IEngineService, Location)}&nbsp;instead.
     */
    public PrivateAsset(Resource resourceLocation, Location location)
    {
        this(resourceLocation, null, location);
    }

    public PrivateAsset(Resource resourceLocation, IEngineService assetService,
            Location location)
    {
        super(resourceLocation, location);

        Defense.notNull(assetService, "assetService");

        _assetService = assetService;
    }

    /**
     * Gets the localized version of the resource. Build the URL for the resource. If possible, the
     * application's {@link ExternalAsset}is located, to copy the resource to a directory
     * visible to the web server.
     */

    public String buildURL()
    {
        String path = getResourceLocation().getPath();

        ILink link = _assetService.getLink(false, path);
        
        return link.getURL();
    }

    public InputStream getResourceAsStream()
    {
        Resource location = getResourceLocation();

        try
        {
            URL url = location.getResourceURL();

            return url.openStream();
        }
        catch (Exception ex)
        {
            throw new ApplicationRuntimeException(AssetMessages.noSuchResource(location.getPath()));
        }
    }

}