[Cronet] Handle redirects in CronetHttpURLConnection

components/cronet/android/java/src/org/chromium/net/urlconnection/CronetHttpURLConnection.java

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 package org.chromium.net.urlconnection;
 
 import org.chromium.net.ExtendedResponseInfo;
 import org.chromium.net.ResponseInfo;
 import org.chromium.net.UrlRequest;
 import org.chromium.net.UrlRequestContext;
 import org.chromium.net.UrlRequestException;
 import org.chromium.net.UrlRequestListener;
 
 import java.io.IOException;
 import java.io.InputStream;
 import java.net.HttpURLConnection;
+import java.net.MalformedURLException;
 import java.net.URL;
 import java.nio.ByteBuffer;
 
 /**
  * An implementation of HttpURLConnection that uses Cronet to send requests and
  * receive response. This class inherits a {@code connected} field from the
  * superclass. That field indicates whether a connection has ever been
  * attempted.
  */
 public class CronetHttpURLConnection extends HttpURLConnection {
     private final UrlRequestContext mUrlRequestContext;
     private final MessageLoop mMessageLoop;
     private final UrlRequest mRequest;
 
     private CronetInputStream mInputStream;
     private ResponseInfo mResponseInfo;
     private ByteBuffer mResponseByteBuffer;
+    private boolean mOnRedirectCalled = false;
 
     protected CronetHttpURLConnection(URL url,
             UrlRequestContext urlRequestContext) {
         super(url);
         mUrlRequestContext = urlRequestContext;
         mMessageLoop = new MessageLoop();
         mRequest = mUrlRequestContext.createRequest(url.toString(),
                 new CronetUrlRequestListener(), mMessageLoop);
         mInputStream = new CronetInputStream(this);
     }
@@ skipping 56 matching lines @@
         return mResponseInfo.getHttpStatusCode();
     }
 
     /**
      * Returns an InputStream for reading data from the resource pointed by this
      * URLConnection.
      */
     @Override
     public InputStream getInputStream() throws IOException {
         connect();
+        if (mResponseInfo == null) {
+            throw new IOException();
+        }
+        if (!instanceFollowRedirects && mOnRedirectCalled) {
+            throw new IOException("Cannot read response body of a redirect.");
+        }
         return mInputStream;
     }
 
     /**
      * Adds the given property to the request header.
      */
     @Override
     public final void addRequestProperty(String key, String value) {
         // Note that Cronet right now does not allow setting multiple headers
         // of the same key, see crbug.com/432719 for more details.
@@ skipping 49 matching lines @@
             mResponseInfo = info;
             mResponseByteBuffer = ByteBuffer.allocate(byteBuffer.capacity());
             mResponseByteBuffer.put(byteBuffer);
             mResponseByteBuffer.flip();
             mMessageLoop.postQuitTask();
         }
 
         @Override
         public void onRedirect(UrlRequest request, ResponseInfo info,
                 String newLocationUrl) {
-            // TODO(xunjieli): Handle redirect and test it.
+            mOnRedirectCalled = true;
+            if (instanceFollowRedirects) {
+                try {
+                    url = new URL(newLocationUrl);
+                } catch (MalformedURLException e) {
+                    // Ignored.
+                }
+            } else {
+                mResponseInfo = info;
+                mRequest.cancel();
+                setResponseDataCompleted();
+            }
         }
 
         @Override
         public void onSucceeded(UrlRequest request, ExtendedResponseInfo info) {
             mResponseInfo = info.getResponseInfo();
             setResponseDataCompleted();
         }
 
         @Override
         public void onFailed(UrlRequest request, ResponseInfo info,
                 UrlRequestException exception) {
             // TODO(xunjieli): Handle failure.
             setResponseDataCompleted();
         }
 
         /**
          * Notifies {@link #mInputStream} that transferring of response data has
          * completed.
          */
         private void setResponseDataCompleted() {
             if (mInputStream != null) {
                 mInputStream.setResponseDataCompleted();
             }
             mMessageLoop.postQuitTask();
         }
     }
 }