Make pre-processing work per request and accompanying response.

Author: Noor Dawod

library/src/main/java/com/loopj/android/http/AsyncHttpClient.java

@@ -122,9 +122,6 @@ public class AsyncHttpClient {
     public static final String HEADER_CONTENT_DISPOSITION = "Content-Disposition";
     public static final String HEADER_ACCEPT_ENCODING = "Accept-Encoding";
     public static final String ENCODING_GZIP = "gzip";
-    public static final String ATTR_PRE_PROCESSED = "ahc.pre-processed";
-    public static final String TRUE = "true";
-    public static final String FALSE = "false";
 
     public static final int DEFAULT_MAX_CONNECTIONS = 10;
     public static final int DEFAULT_SOCKET_TIMEOUT = 10 * 1000;
@@ -141,7 +138,6 @@ public class AsyncHttpClient {
     private ExecutorService threadPool;
     private final Map<Context, List<RequestHandle>> requestMap;
     private final Map<String, String> clientHeaderMap;
-    private PreProcessingInterface preProcessor;
     private boolean isUrlEncodingEnabled = true;
 
     /**
@@ -276,7 +272,6 @@ public void process(HttpResponse response, HttpContext context) {
                 if (entity == null) {
                     return;
                 }
-
                 final Header encoding = entity.getContentEncoding();
                 if (encoding != null) {
                     for (HeaderElement element : encoding.getElements()) {
@@ -286,18 +281,6 @@ public void process(HttpResponse response, HttpContext context) {
                         }
                     }
                 }
-
-                if (preProcessor != null) {
-                    // Handle pre-processing only once.
-                    Object isPreProcessed = context.getAttribute(ATTR_PRE_PROCESSED);
-                    if (isPreProcessed != null && isPreProcessed.equals(TRUE)) {
-                        // Pre-process this request.
-                        preProcessor.onPreProcessResponse(response);
-
-                        // Indicate that this request has passed pre-processing.
-                        context.removeAttribute(ATTR_PRE_PROCESSED);
-                    }
-                }
             }
         });
 
@@ -317,18 +300,6 @@ public void process(final HttpRequest request, final HttpContext context) throws
                         authState.setCredentials(creds);
                     }
                 }
-
-                if (preProcessor != null) {
-                    // Handle pre-processing only once.
-                    Object isPreProcessed = context.getAttribute(ATTR_PRE_PROCESSED);
-                    if (isPreProcessed == null || !isPreProcessed.equals(TRUE)) {
-                        // Pre-process this request.
-                        preProcessor.onPreProcessRequest(request);
-
-                        // Indicate that this request has passed pre-processing.
-                        context.setAttribute(ATTR_PRE_PROCESSED, TRUE);
-                    }
-                }
             }
         }, 0);
 
@@ -399,25 +370,6 @@ public ExecutorService getThreadPool() {
         return threadPool;
     }
 
-    /**
-     * Sets a handler to be used for pre-processing requests and responses.
-     *
-     * @param handler an instance of {@link PreProcessingInterface} to use for
-     *        pre-processing requests and responses
-     */
-    public void setPreProcessor(PreProcessingInterface handler) {
-        this.preProcessor = handler;
-    }
-
-    /**
-     * Returns the current handler for pre-processing requests and responses.
-     *
-     * @return current handler used, or null if none is defined
-     */
-    public PreProcessingInterface getPreProcessor() {
-        return preProcessor;
-    }
-
     /**
      * Get the default threading pool to be used for this HTTP client.
      *

library/src/main/java/com/loopj/android/http/AsyncHttpRequest.java

@@ -33,15 +33,16 @@
 /**
  * Internal class, representing the HttpRequest, done in asynchronous manner
  */
-public class AsyncHttpRequest implements Runnable {
+public class AsyncHttpRequest implements PreProcessInterface, Runnable {
     private final AbstractHttpClient client;
     private final HttpContext context;
     private final HttpUriRequest request;
     private final ResponseHandlerInterface responseHandler;
     private int executionCount;
-    private boolean isCancelled = false;
-    private boolean cancelIsNotified = false;
-    private boolean isFinished = false;
+    private boolean isCancelled;
+    private boolean cancelIsNotified;
+    private boolean isFinished;
+    private boolean isRequestPreProcessed;
 
     public AsyncHttpRequest(AbstractHttpClient client, HttpContext context, HttpUriRequest request, ResponseHandlerInterface responseHandler) {
         this.client = client;
@@ -50,12 +51,26 @@ public AsyncHttpRequest(AbstractHttpClient client, HttpContext context, HttpUriR
         this.responseHandler = responseHandler;
     }
 
+    @Override
+    public void onPreProcess() {
+    }
+
     @Override
     public void run() {
         if (isCancelled()) {
             return;
         }
 
+        // Carry out pre-processing for this request only once.
+        if (!isRequestPreProcessed) {
+            isRequestPreProcessed = true;
+            onPreProcess();
+        }
+
+        if (isCancelled()) {
+            return;
+        }
+
         if (responseHandler != null) {
             responseHandler.sendStartMessage();
         }
@@ -98,6 +113,10 @@ private void makeRequest() throws IOException {
         HttpResponse response = client.execute(request, context);
 
         if (!isCancelled() && responseHandler != null) {
+            // Carry out pre-processing for this response.
+            responseHandler.onPreProcess();
+
+            // The response is ready, handle it.
             responseHandler.sendResponseMessage(response);
         }
     }

library/src/main/java/com/loopj/android/http/AsyncHttpResponseHandler.java

@@ -79,6 +79,7 @@
  * </pre>
  */
 public abstract class AsyncHttpResponseHandler implements ResponseHandlerInterface {
+
     private static final String LOG_TAG = "AsyncHttpResponseHandler";
 
     protected static final int SUCCESS_MESSAGE = 0;
@@ -217,6 +218,11 @@ public void onFinish() {
         // default log warning is not necessary, because this method is just optional notification
     }
 
+    @Override
+    public void onPreProcess() {
+        // default action is to do nothing...
+    }
+
     /**
      * Fired when a request returns successfully, override to handle in your own code
      *

library/src/main/java/com/loopj/android/http/JsonHttpResponseHandler.java

@@ -36,6 +36,7 @@
  * Additionally, you can override the other event methods from the parent class.
  */
 public class JsonHttpResponseHandler extends TextHttpResponseHandler {
+
     private static final String LOG_TAG = "JsonHttpResponseHandler";
 
     /**

library/src/main/java/com/loopj/android/http/JsonStreamerEntity.java

@@ -56,8 +56,8 @@ public class JsonStreamerEntity implements HttpEntity {
     // automatically enlarge the buffer.
     private static final StringBuilder BUILDER = new StringBuilder(128);
 
-    private static final byte[] JSON_TRUE = AsyncHttpClient.TRUE.getBytes();
-    private static final byte[] JSON_FALSE = AsyncHttpClient.FALSE.getBytes();
+    private static final byte[] JSON_TRUE = "true".getBytes();
+    private static final byte[] JSON_FALSE = "false".getBytes();
     private static final byte[] JSON_NULL = "null".getBytes();
     private static final byte[] STREAM_NAME = escape("name");
     private static final byte[] STREAM_TYPE = escape("type");

library/src/main/java/com/loopj/android/http/PreProcessInterface.java

@@ -0,0 +1,35 @@
+/*
+    Android Asynchronous Http Client
+    Copyright (c) 2011 James Smith <[email protected]>
+    http://loopj.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 com.loopj.android.http;
+
+/**
+ * This interface is used to define a pre-processing handler. The handler is
+ * called once for a request and once for a response.
+ *
+ * @author Noor Dawod <[email protected]>
+ */
+public interface PreProcessInterface {
+
+    /**
+     * This method is called once by the system when either a request or a response
+     * needs pre-processing. The library makes sure that each request and each
+     * response is pre-processed only once.
+     */
+    void onPreProcess();
+}

library/src/main/java/com/loopj/android/http/ResponseHandlerInterface.java

@@ -27,7 +27,7 @@
 /**
  * Interface to standardize implementations
  */
-public interface ResponseHandlerInterface {
+public interface ResponseHandlerInterface extends PreProcessInterface {
 
     /**
      * Returns data whether request completed successfully

library/src/main/java/com/loopj/android/http/TextHttpResponseHandler.java

@@ -56,6 +56,7 @@
  * </pre>
  */
 public abstract class TextHttpResponseHandler extends AsyncHttpResponseHandler {
+
     private static final String LOG_TAG = "TextHttpResponseHandler";
 
     /**
@@ -119,5 +120,4 @@ public static String getResponseString(byte[] stringBytes, String charset) {
             return null;
         }
     }
-
 }