added json support

git-svn-id: http://jclouds.googlecode.com/svn/trunk@1621 3d8758e0-26b5-11de-8745-db77d3ebf521

core/pom.xml

@@ -101,6 +101,11 @@
             <artifactId>bcprov-jdk15</artifactId>
             <version>140</version>
         </dependency>
+        <dependency>
+            <groupId>com.google.code.gson</groupId>
+            <artifactId>gson</artifactId>
+            <version>1.3</version>
+        </dependency>
     </dependencies>
 
 </project>

core/src/main/java/org/jclouds/http/functions/ParseJson.java

@@ -0,0 +1,90 @@
+/**
+ *
+ * Copyright (C) 2009 Global Cloud Specialists, Inc. <info@globalcloudspecialists.com>
+ *
+ * ====================================================================
+ * 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.jclouds.http.functions;
+
+import static org.jclouds.http.HttpConstants.PROPERTY_JSON_DEBUG;
+
+import java.io.InputStream;
+
+import javax.annotation.Resource;
+
+import org.apache.commons.io.IOUtils;
+import org.jclouds.http.HttpResponse;
+import org.jclouds.http.HttpResponseException;
+import org.jclouds.logging.Logger;
+
+import com.google.common.base.Function;
+import com.google.gson.Gson;
+import com.google.inject.Inject;
+import com.google.inject.name.Named;
+
+/**
+ * This object will parse the body of an HttpResponse and return the result of type <T> back to the
+ * caller.
+ * 
+ * @author Adrian Cole
+ */
+public abstract class ParseJson<T> implements Function<HttpResponse, T> {
+
+   @Inject(optional = true)
+   @Named(PROPERTY_JSON_DEBUG)
+   private boolean suckFirst = false;
+   @Resource
+   protected Logger logger = Logger.NULL;
+   protected final Gson gson;
+
+   public ParseJson(Gson gson) {
+      this.gson = gson;
+   }
+
+   /**
+    * parses the http response body to create a new {@code <T>}.
+    */
+   public T apply(HttpResponse from) {
+      InputStream gson = from.getContent();
+      String response = null;
+      try {
+         if (suckFirst) {
+            response = IOUtils.toString(gson);
+            logger.trace("received content %n%s", response);
+            IOUtils.closeQuietly(gson);
+            gson = IOUtils.toInputStream(response);
+         }
+         return apply(gson);
+      } catch (Exception e) {
+         StringBuilder message = new StringBuilder();
+         message.append("Error parsing input");
+         if (response != null) {
+            message.append("\n").append(response);
+         }
+         logger.error(e, message.toString());
+         throw new HttpResponseException(message.toString()+"\n"+from, null, from, e);
+      } finally {
+         IOUtils.closeQuietly(gson);
+      }
+
+   }
+
+   protected abstract T apply(InputStream stream);
+}