| // Copyright 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. |
| |
| package org.apache.tapestry.engine; |
| |
| import java.io.IOException; |
| |
| import org.apache.tapestry.ApplicationRuntimeException; |
| import org.apache.tapestry.IRequestCycle; |
| import org.apache.tapestry.Tapestry; |
| import org.apache.tapestry.request.RequestContext; |
| import org.apache.tapestry.util.StringSplitter; |
| import org.apache.tapestry.util.io.DataSqueezer; |
| |
| /** |
| * Abstract base class for implementing engine services. Instances of services |
| * are shared by many engines and threads, so they must be threadsafe. |
| * |
| * <p> |
| * Note; too much of the URL encoding/decoding stategy is fixed here. |
| * A future release of Tapestry may extract this strategy, allowing developers |
| * to choose the method via which URLs are encoded. |
| * |
| * @see org.apache.tapestry.engine.AbstractEngine#getService(String) |
| * |
| * |
| * @author Howard Lewis Ship |
| * @version $Id$ |
| * @since 1.0.3 |
| * |
| **/ |
| |
| public abstract class AbstractService implements IEngineService |
| { |
| /** |
| * Constructs a link for the service. |
| * |
| * @param cycle the request cycle |
| * @param serviceName the name of the service |
| * @param serviceContext context related to the service itself which is added to the URL as-is |
| * @param parameters additional service parameters provided by the component; |
| * this is application specific information, and is encoded with |
| * {@link java.net.URLEncoder#encode(String)} before being added |
| * to the query. |
| * @param stateful if true, the final URL must be encoded with the HttpSession id |
| * |
| **/ |
| |
| protected ILink constructLink( |
| IRequestCycle cycle, |
| String serviceName, |
| String[] serviceContext, |
| Object[] parameters, |
| boolean stateful) |
| { |
| DataSqueezer squeezer = cycle.getEngine().getDataSqueezer(); |
| String[] squeezed = null; |
| |
| try |
| { |
| squeezed = squeezer.squeeze(parameters); |
| } |
| catch (IOException ex) |
| { |
| throw new ApplicationRuntimeException(ex); |
| } |
| |
| return new EngineServiceLink(cycle, serviceName, serviceContext, squeezed, stateful); |
| } |
| |
| /** |
| * Returns the service context as an array of Strings. |
| * Returns null if there are no service context strings. |
| * |
| **/ |
| |
| protected String[] getServiceContext(RequestContext context) |
| { |
| String service = context.getParameter(Tapestry.SERVICE_QUERY_PARAMETER_NAME); |
| |
| int slashx = service.indexOf('/'); |
| |
| if (slashx < 0) |
| return null; |
| |
| String serviceContext = service.substring(slashx + 1); |
| |
| return new StringSplitter('/').splitToArray(serviceContext); |
| } |
| |
| /** |
| * Returns the service parameters as an array of Strings. |
| * |
| **/ |
| |
| protected Object[] getParameters(IRequestCycle cycle) |
| { |
| RequestContext context = cycle.getRequestContext(); |
| |
| String[] squeezed = context.getParameters(Tapestry.PARAMETERS_QUERY_PARAMETER_NAME); |
| |
| if (Tapestry.size(squeezed) == 0) |
| return squeezed; |
| |
| try |
| { |
| DataSqueezer squeezer = cycle.getEngine().getDataSqueezer(); |
| |
| return squeezer.unsqueeze(squeezed); |
| } |
| catch (IOException ex) |
| { |
| throw new ApplicationRuntimeException(ex); |
| } |
| } |
| } |