Issue 89: fixed npe in google appengine live

git-svn-id: http://jclouds.googlecode.com/svn/trunk@2592 3d8758e0-26b5-11de-8745-db77d3ebf521

demos/gae-tweetstore-spring/src/main/java/org/jclouds/demo/tweetstore/config/SpringAppConfig.java

@@ -13,6 +13,7 @@ import java.util.Properties;
 
 import javax.annotation.PostConstruct;
 import javax.annotation.PreDestroy;
+import javax.inject.Singleton;
 
 import org.jclouds.blobstore.BlobStoreContext;
 import org.jclouds.blobstore.BlobStoreContextBuilder;
@@ -37,89 +38,92 @@ import com.google.common.io.Closeables;
  * @see SpringServletConfig
  */
 @Configuration
+@Singleton
 public class SpringAppConfig implements ResourceLoaderAware {
-    /*
+   /*
-     * The call to TwitterContextFactory.createContext in initialize()
+    * The call to TwitterContextFactory.createContext in initialize() must be carried out before the
-     * must be carried out before the servlet context loads, otherwise the
+    * servlet context loads, otherwise the GAE will throw an access exception. For this reason, this
-     * GAE will throw an access exception.
+    * code cannot be in the default servlet context loaded by the DispatcherServlet, but is executed
-     * For this reason, this code cannot be in the default servlet context
+    * in the root application context (which is processed by a listener).
-     * loaded by the DispatcherServlet, but is executed in the root application
+    */
-     * context (which is processed by a listener).
-     */
-    
-    private final Properties props = new Properties();
 
-    Map<String, BlobStoreContext<?, ?>> providerTypeToBlobStoreMap;
+   private final Properties props = new Properties();
-    TwitterClient twitterClient;
-    String container;
 
-    @SuppressWarnings("unchecked")
+   Map<String, BlobStoreContext<?, ?>> providerTypeToBlobStoreMap;
-    @PostConstruct
+   TwitterClient twitterClient;
-    public void initialize() {
+   String container;
-        // shared across all blobstores and used to retrieve tweets
-        twitterClient = TwitterContextFactory.createContext(props,
-                new GaeHttpCommandExecutorServiceModule()).getApi();
 
-        // common namespace for storing tweets.
+   private boolean initializing;
-        container = checkNotNull(props.getProperty(PROPERTY_TWEETSTORE_CONTAINER),
-                                 PROPERTY_TWEETSTORE_CONTAINER);
-        ImmutableList<String> contextBuilderClassNames = ImmutableList.<String>of(
-                checkNotNull(props.getProperty(PROPERTY_BLOBSTORE_CONTEXTBUILDERS),
-                             PROPERTY_BLOBSTORE_CONTEXTBUILDERS)
-                 .split(","));
 
-        // instantiate and store references to all blobstores by provider name
+   @SuppressWarnings("unchecked")
-        providerTypeToBlobStoreMap = Maps.newHashMap();
+   @PostConstruct
-        for (String className : contextBuilderClassNames) {
+   public void initialize() {
-            Class<BlobStoreContextBuilder<?, ?>> builderClass;
+      if (initializing)
-            Constructor<BlobStoreContextBuilder<?, ?>> constructor;
+         return;
-            String name;
+      initializing = true;
-            BlobStoreContext<?, ?> context;
+      // shared across all blobstores and used to retrieve tweets
-            try {
+      twitterClient = TwitterContextFactory.createContext(props,
-                builderClass = (Class<BlobStoreContextBuilder<?, ?>>) Class.forName(className);
+               new GaeHttpCommandExecutorServiceModule()).getApi();
-                name = builderClass.getSimpleName().replaceAll("BlobStoreContextBuilder", "");
-                constructor = builderClass.getConstructor(Properties.class);
-                context = constructor.newInstance(props)
-                          .withModules(new GaeHttpCommandExecutorServiceModule())
-                          .buildContext();
-            } catch (Exception e) {
-                throw new RuntimeException("error instantiating " + className, e);
-            }
-            providerTypeToBlobStoreMap.put(name, context);
-        }
 
-        // get a queue for submitting store tweet requests
+      // common namespace for storing tweets.
-        Queue queue = QueueFactory.getQueue("twitter");
+      container = checkNotNull(props.getProperty(PROPERTY_TWEETSTORE_CONTAINER),
-        // submit a job to store tweets for each configured blobstore
+               PROPERTY_TWEETSTORE_CONTAINER);
-        for (String name : providerTypeToBlobStoreMap.keySet()) {
+      ImmutableList<String> contextBuilderClassNames = ImmutableList.<String> of(checkNotNull(
-            queue.add(url("/store/do").header("context", name).method(Method.GET));
+               props.getProperty(PROPERTY_BLOBSTORE_CONTEXTBUILDERS),
-        }
+               PROPERTY_BLOBSTORE_CONTEXTBUILDERS).split(","));
-    }
 
-    @PreDestroy
+      // instantiate and store references to all blobstores by provider name
-    public void destroy() {
+      providerTypeToBlobStoreMap = Maps.newHashMap();
-        for (BlobStoreContext<?, ?> context : providerTypeToBlobStoreMap.values()) {
+      for (String className : contextBuilderClassNames) {
-            context.close();
+         Class<BlobStoreContextBuilder<?, ?>> builderClass;
-        }
+         Constructor<BlobStoreContextBuilder<?, ?>> constructor;
-    }
+         String name;
+         BlobStoreContext<?, ?> context;
+         try {
+            builderClass = (Class<BlobStoreContextBuilder<?, ?>>) Class.forName(className);
+            name = builderClass.getSimpleName().replaceAll("BlobStoreContextBuilder", "");
+            constructor = builderClass.getConstructor(Properties.class);
+            context = constructor.newInstance(props).withModules(
+                     new GaeHttpCommandExecutorServiceModule()).buildContext();
+         } catch (Exception e) {
+            throw new RuntimeException("error instantiating " + className, e);
+         }
+         providerTypeToBlobStoreMap.put(name, context);
+      }
 
-    /*
+      // get a queue for submitting store tweet requests
-     * (non-Javadoc)
+      Queue queue = QueueFactory.getQueue("twitter");
-     * 
+      // submit a job to store tweets for each configured blobstore
-     * @see
+      for (String name : providerTypeToBlobStoreMap.keySet()) {
-     * org.springframework.context.ResourceLoaderAware#setResourceLoader(org
+         queue.add(url("/store/do").header("context", name).method(Method.GET));
-     * .springframework.core.io.ResourceLoader)
+      }
-     */
+   }
-    @Override
+
-    public void setResourceLoader(ResourceLoader resourceLoader) {
+   @PreDestroy
-        InputStream input = null;
+   public void destroy() {
-        try {
+      for (BlobStoreContext<?, ?> context : providerTypeToBlobStoreMap.values()) {
-            input = resourceLoader.getResource("/WEB-INF/jclouds.properties").getInputStream();
+         context.close();
-            props.load(input);
+      }
-        } catch (IOException e) {
+   }
-            throw new RuntimeException(e);
+
-        } finally {
+   /*
-            Closeables.closeQuietly(input);
+    * (non-Javadoc)
-        }        
+    * 
-    }
+    * @see org.springframework.context.ResourceLoaderAware#setResourceLoader(org
+    * .springframework.core.io.ResourceLoader)
+    */
+   @Override
+   public void setResourceLoader(ResourceLoader resourceLoader) {
+      InputStream input = null;
+      try {
+         input = resourceLoader.getResource("/WEB-INF/jclouds.properties").getInputStream();
+         props.load(input);
+         if (!initializing)
+            initialize();
+      } catch (IOException e) {
+         throw new RuntimeException(e);
+      } finally {
+         Closeables.closeQuietly(input);
+      }
+   }
 }

demos/gae-tweetstore-spring/src/main/java/org/jclouds/demo/tweetstore/config/SpringServletConfig.java

@@ -1,21 +1,33 @@
+/**
+ *
+ * Copyright (C) 2009 Cloud Conscious, LLC. <info@cloudconscious.com>
+ *
+ * ====================================================================
+ * 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.jclouds.demo.tweetstore.config;
 
 import static com.google.common.base.Preconditions.checkNotNull;
 
 import java.util.Map;
 
-import javax.inject.Inject;
-import javax.servlet.Servlet;
-import javax.servlet.ServletConfig;
-import javax.servlet.ServletException;
-
 import org.jclouds.demo.tweetstore.controller.AddTweetsController;
 import org.jclouds.demo.tweetstore.controller.StoreTweetsController;
 import org.jclouds.demo.tweetstore.functions.ServiceToStoredTweetStatuses;
-import org.springframework.beans.factory.BeanCreationException;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
-import org.springframework.web.context.ServletConfigAware;
+import org.springframework.web.context.WebApplicationContext;
 import org.springframework.web.servlet.HandlerAdapter;
 import org.springframework.web.servlet.HandlerMapping;
 import org.springframework.web.servlet.handler.SimpleServletHandlerAdapter;
@@ -24,74 +36,54 @@ import org.springframework.web.servlet.handler.SimpleUrlHandlerMapping;
 import com.google.common.collect.Maps;
 
 /**
- * Creates servlets (using resources from the {@link SpringAppConfig}) and mappings.
+ * Creates servlets,(using resources from the {@link SpringAppConfig}) and mappings.
  * 
  * @author Andrew Phillips
- * @see SpringAppConfig
  */
 @Configuration
-public class SpringServletConfig implements ServletConfigAware {
+public class SpringServletConfig {
-    private ServletConfig servletConfig;
-    
-    @Inject
-    private SpringAppConfig appConfig;
-    
-    @Bean
-    public StoreTweetsController storeTweetsController() {
-        StoreTweetsController controller = new StoreTweetsController(appConfig.providerTypeToBlobStoreMap, 
-                appConfig.container, appConfig.twitterClient);
-        injectServletConfig(controller);        
-        return controller;
-    }
 
-    @Bean
+   @Bean
-    public AddTweetsController addTweetsController() {
+   public StoreTweetsController storeTweetsController(SpringAppConfig appConfig) {
-        AddTweetsController controller = new AddTweetsController(appConfig.providerTypeToBlobStoreMap,
+      return new StoreTweetsController(checkNotNull(appConfig.providerTypeToBlobStoreMap,
-                serviceToStoredTweetStatuses());
+               "contexts"), checkNotNull(appConfig.container, "container"), checkNotNull(
-        injectServletConfig(controller);
+               appConfig.twitterClient, "twitterClient"));
-        return controller;
+   }
-    }
-    
-    private void injectServletConfig(Servlet servlet) {
-        checkNotNull(servletConfig);
-        try {
-            servlet.init(servletConfig);
-        } catch (ServletException exception) {
-            throw new BeanCreationException("Unable to instantiate " + servlet, exception);
-        }
-    }
 
-    @Bean
+   @Bean
-    ServiceToStoredTweetStatuses serviceToStoredTweetStatuses() {
+   public AddTweetsController addTweetsController(SpringAppConfig appConfig) {
-        return new ServiceToStoredTweetStatuses(appConfig.providerTypeToBlobStoreMap,
+      return new AddTweetsController(
-                appConfig.container);
+               checkNotNull(appConfig.providerTypeToBlobStoreMap, "contexts"),
-    }
+               serviceToStoredTweetStatuses(appConfig));
-    
+   }
-    @Bean
-    public HandlerMapping handlerMapping() {
-        SimpleUrlHandlerMapping mapping = new SimpleUrlHandlerMapping();
-        Map<String, Object> urlMap = Maps.newHashMapWithExpectedSize(2);
-        urlMap.put("/store/*", storeTweetsController());
-        urlMap.put("/tweets/*", addTweetsController());
-        mapping.setUrlMap(urlMap);
-        /*
-         * "/store" and "/tweets" are part of the servlet mapping and thus stripped
-         * by the mapping if using default settings.
-         */
-        mapping.setAlwaysUseFullPath(true);
-        return mapping;
-    }
-    
-    @Bean
-    public HandlerAdapter servletHandlerAdapter() {
-        return new SimpleServletHandlerAdapter();
-    }
 
-    /* (non-Javadoc)
+   @Bean
-     * @see org.springframework.web.context.ServletConfigAware#setServletConfig(javax.servlet.ServletConfig)
+   ServiceToStoredTweetStatuses serviceToStoredTweetStatuses(SpringAppConfig appConfig) {
-     */
+      return new ServiceToStoredTweetStatuses(checkNotNull(appConfig.providerTypeToBlobStoreMap,
-    @Override
+               "contexts"), checkNotNull(appConfig.container, "container"));
-    public void setServletConfig(ServletConfig servletConfig) {
+   }
-        this.servletConfig = servletConfig;
+
-    }
+   @Bean
+   public HandlerMapping handlerMapping(AddTweetsController add, StoreTweetsController store,
+            WebApplicationContext context) {
+      SimpleUrlHandlerMapping mapping = new SimpleUrlHandlerMapping();
+      mapping.setServletContext(context.getServletContext());
+      Map<String, Object> urlMap = Maps.newHashMapWithExpectedSize(2);
+      urlMap.put("/store/*", checkNotNull(store, "store"));
+      add.setServletContext(checkNotNull(context.getServletContext(), "servletContext"));
+      urlMap.put("/tweets/*", checkNotNull(add, "add"));
+      mapping.setUrlMap(urlMap);
+      /*
+       * "/store" and "/tweets" are part of the servlet mapping and thus stripped by the mapping if
+       * using default settings.
+       */
+      mapping.setAlwaysUseFullPath(true);
+      return mapping;
+   }
+
+   @Bean
+   public HandlerAdapter servletHandlerAdapter() {
+      return new SimpleServletHandlerAdapter();
+   }
 }
+

demos/gae-tweetstore-spring/src/main/java/org/jclouds/demo/tweetstore/controller/AddTweetsController.java

@@ -69,8 +69,9 @@ public class AddTweetsController extends HttpServlet implements
    @Inject
    public AddTweetsController(Map<String, BlobStoreContext<?, ?>> contexts,
             ServiceToStoredTweetStatuses blobStoreContextToContainerResult) {
-      this.contexts = contexts;
+      this.contexts = checkNotNull(contexts, "contexts");
-      this.blobStoreContextToContainerResult = blobStoreContextToContainerResult;
+      this.blobStoreContextToContainerResult = checkNotNull(blobStoreContextToContainerResult,
+               "blobStoreContextToContainerResult");
    }
 
    @Override
@@ -100,6 +101,7 @@ public class AddTweetsController extends HttpServlet implements
       return statuses;
    }
 
+   @Inject
    @Override
    public void setServletContext(ServletContext context) {
       this.servletContext = context;
@@ -107,6 +109,6 @@ public class AddTweetsController extends HttpServlet implements
 
    @Override
    public ServletContext getServletContext() {
-      return checkNotNull(servletContext, "servletContext");
+      return (servletContext != null) ? servletContext : super.getServletContext();
    }
 }