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Diffstat (limited to 'tags/java/sca/2.0-M4-RC1/modules/wicket/src/main/java/org/apache/tuscany/sca/wicket/TuscanyComponentInjector.java')
| -rw-r--r-- | tags/java/sca/2.0-M4-RC1/modules/wicket/src/main/java/org/apache/tuscany/sca/wicket/TuscanyComponentInjector.java | 158 |
1 files changed, 158 insertions, 0 deletions
diff --git a/tags/java/sca/2.0-M4-RC1/modules/wicket/src/main/java/org/apache/tuscany/sca/wicket/TuscanyComponentInjector.java b/tags/java/sca/2.0-M4-RC1/modules/wicket/src/main/java/org/apache/tuscany/sca/wicket/TuscanyComponentInjector.java new file mode 100644 index 0000000000..b1e9097cdf --- /dev/null +++ b/tags/java/sca/2.0-M4-RC1/modules/wicket/src/main/java/org/apache/tuscany/sca/wicket/TuscanyComponentInjector.java @@ -0,0 +1,158 @@ +/* + * Licensed to the Apache Software Foundation (ASF) under one + * or more contributor license agreements. See the NOTICE file + * distributed with this work for additional information + * regarding copyright ownership. The ASF licenses this file + * to you 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.tuscany.sca.wicket; +import javax.servlet.ServletContext; + +import org.apache.wicket.Application; +import org.apache.wicket.IClusterable; +import org.apache.wicket.MetaDataKey; +import org.apache.wicket.Session; +import org.apache.wicket.application.IComponentInstantiationListener; +import org.apache.wicket.injection.ComponentInjector; +import org.apache.wicket.injection.web.InjectorHolder; +import org.apache.wicket.model.Model; +import org.apache.wicket.protocol.http.WebApplication; + +/** + * {@link IComponentInstantiationListener} that injects component properties annotated with {@link + * SpringBean} annotations. + * + * To install in yourapplication.init() call + * <code>addComponentInstantiationListener(new SpringComponentInjector(this));</code> Non-wicket + * components such as {@link Session}, {@link Model}, and any other pojo can be injected by calling + * <code>InjectorHolder.getInjector().inject(this)</code> in their constructor. + * + * Based on code from Apache Wicket by Igor Vaynberg and Justin Lee + */ +public class TuscanyComponentInjector extends ComponentInjector +{ + + /** + * Metadata key used to store application context holder in application's metadata + */ + private static MetaDataKey<ApplicationContextHolder> CONTEXT_KEY = new MetaDataKey<ApplicationContextHolder>() + { + + private static final long serialVersionUID = 1L; + + }; + + /** + * Constructor used when spring application context is declared in the spring standard way and + * can be located through {@link + * WebApplicationContextUtils#getRequiredWebApplicationContext(ServletContext)} + * + * @param webapp + * wicket web application + */ + public TuscanyComponentInjector(WebApplication webapp) + { + // locate application context through spring's default location + // mechanism and pass it on to the proper constructor + this(webapp, webapp.getServletContext()); + } + + /** + * Constructor + * + * @param webapp + * wicket web application + * @param ctx + * spring's application context + */ + public TuscanyComponentInjector(WebApplication webapp, ServletContext ctx) + { + if (webapp == null) + { + throw new IllegalArgumentException("Argument [[webapp]] cannot be null"); + } + + if (ctx == null) + { + throw new IllegalArgumentException("Argument [[ctx]] cannot be null"); + } + + // store context in application's metadata ... + webapp.setMetaData(CONTEXT_KEY, new ApplicationContextHolder(ctx)); + + // ... and create and register the annotation aware injector + InjectorHolder.setInjector(new TuscanyInjector(new ContextLocator())); + } + + /** + * This is a holder for the application context. The reason we need a holder is that metadata + * only supports storing serializable objects but application context is not. The holder acts as + * a serializable wrapper for the context. Notice that although holder implements IClusterable + * it really is not because it has a reference to non serializable context - but this is ok + * because metadata objects in application are never serialized. + * + * @author ivaynberg + * + */ + private static class ApplicationContextHolder implements IClusterable + { + private static final long serialVersionUID = 1L; + + private final ServletContext context; + + /** + * Constructor + * + * @param context + */ + public ApplicationContextHolder(ServletContext context) + { + this.context = context; + } + + /** + * @return the context + */ + public ServletContext getContext() + { + return context; + } + } + + /** + * A context locator that locates the context in application's metadata. This locator also keeps + * a transient cache of the lookup. + * + * @author ivaynberg + * + */ + private static class ContextLocator implements IContextLocator + { + private transient ServletContext context; + + private static final long serialVersionUID = 1L; + + public ServletContext getServletContext() + { + if (context == null) + { + context = (Application.get().getMetaData(CONTEXT_KEY)).getContext(); + } + return context; + } + + } + +} |