PackagedWeblet.java

/*
 * Copyright 2005 John R. Fallows
 *
 * 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 net.java.dev.weblets.packaged;

import net.java.dev.weblets.*;
import net.java.dev.weblets.util.CopyStrategyImpl;
import net.java.dev.weblets.util.CopyStrategy;

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

/**
 * The standard packaged weblet serves resources from a standard weblet packaging
 */
public class PackagedWeblet extends Weblet {
    /**
     * init method which is called by default to process the parameters
     *
     * @param config the webletconfig to be processed
     */
    public void init(WebletConfig config) {
        super.init(config);
        // fetch the weblets init param
        String packageName = config.getInitParameter("package");
        // fetch the resource root param
        String resourceRoot = config.getInitParameter("resourceRoot");
        // String cacheTimeout = config.getInitParameter("cachecontrol-timeout");
        // init param missing, lets throw an error
        if (packageName == null && resourceRoot == null) {
            throw new WebletException("Missing either init parameter \"package\" or " + " or init parameter \"resourceRoot\" for " + " Weblet \""
                    + config.getWebletName() + "\"");
        }
        // the init was successful we now have all we need
        _resourceRoot = (packageName != null) ? packageName.replace('.', '/') : resourceRoot;
        // optional init param
    }

    public void service(WebletRequest request, WebletResponse response) throws IOException {
        String resourcePath = _resourceRoot + request.getPathInfo();
        // lets build up our filter chain which in our case is a binary filter for standard
        // processing and our text processing filter for text resources with included
        // weblet: functions
        CopyStrategyImpl copyProvider = new CopyStrategyImpl();
        URL url = WebletResourceloadingUtils.getInstance().getResourceUrl(request, resourcePath);
        WebletResourceloadingUtils.getInstance().loadFromUrl(getWebletConfig(), request, response, url, copyProvider);
    }

    /**
     * Second Weblet entry point the service stream method is used internally for Weblets 1.1 by our asynchronous reporting interface <p/> It basically does the
     * same as service but must be servlet independend (aka it cannot rely on a base servlet or the external request of the weblet request object <p/> If you do
     * not trigger the reporting subengine then you can omit this interface it is not used internally
     *
     * @param pathInfo
     * @param mimetype
     * @return
     * @throws IOException
     * @throws WebletException
     */
    public InputStream serviceStream(String pathInfo, String mimetype) throws IOException, WebletException {
        String resourcePath = _resourceRoot + pathInfo;
        // lets build up our filter chain which in our case is a binary filter for standard
        // processing and our text processing filter for text resources with included
        // weblet: functions
        CopyStrategy copyProvider = new CopyStrategyImpl();
        URL url = WebletResourceloadingUtils.getInstance().getResourceUrl(resourcePath);
        if (url == null)
            return null;
        // our utils should handle the standard case
        URLConnection conn = url.openConnection();
        long lastmodified = conn.getLastModified();
        if (mimetype == null)
            mimetype = getWebletConfig().getMimeType(resourcePath);
        return copyProvider.wrapInputStream(getWebletConfig().getWebletName(), mimetype, conn.getInputStream()); // To change body of implemented methods use
        // File | Settings | File Templates.
    }

    public void destroy() {
        _resourceRoot = null;
        super.destroy();
	}

	private String	_resourceRoot;
}