4 files changed, 83 insertions, 16 deletions
diff --git a/base/android/content_uri_utils.cc b/base/android/content_uri_utils.cc
index 0e0c0ea..0482fee 100644
--- a/base/android/content_uri_utils.cc
+++ b/base/android/content_uri_utils.cc
@@ -35,4 +35,14 @@ File OpenContentUriForRead(const FilePath& content_uri) {
   return File(fd);
 }
 
+std::string GetContentUriMimeType(const FilePath& content_uri) {
+  JNIEnv* env = base::android::AttachCurrentThread();
+  ScopedJavaLocalRef<jstring> j_uri =
+      ConvertUTF8ToJavaString(env, content_uri.value());
+  ScopedJavaLocalRef<jstring> j_mime =
+      Java_ContentUriUtils_getMimeType(
+          env, base::android::GetApplicationContext(), j_uri.obj());
+  return base::android::ConvertJavaStringToUTF8(env, j_mime.obj());
+}
+
 }  // namespace base
diff --git a/base/android/content_uri_utils.h b/base/android/content_uri_utils.h
index 827ec92..e66b770 100644
--- a/base/android/content_uri_utils.h
+++ b/base/android/content_uri_utils.h
@@ -16,13 +16,17 @@ namespace base {
 
 bool RegisterContentUriUtils(JNIEnv* env);
 
-// Opens a content uri for read and returns the file descriptor to the caller.
-// Returns -1 if the uri is invalid.
+// Opens a content URI for read and returns the file descriptor to the caller.
+// Returns -1 if the URI is invalid.
 BASE_EXPORT File OpenContentUriForRead(const FilePath& content_uri);
 
-// Check whether a content uri exists.
+// Check whether a content URI exists.
 BASE_EXPORT bool ContentUriExists(const FilePath& content_uri);
 
+// Gets MIME type from a content URI. Returns an empty string if the URI is
+// invalid.
+BASE_EXPORT std::string GetContentUriMimeType(const FilePath& content_uri);
+
 }  // namespace base
 
 #endif  // BASE_ANDROID_CONTENT_URI_UTILS_H_
diff --git a/base/android/content_uri_utils_unittest.cc b/base/android/content_uri_utils_unittest.cc
new file mode 100644
index 0000000..c762035
--- /dev/null
+++ b/base/android/content_uri_utils_unittest.cc
@@ -0,0 +1,37 @@
+// 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.
+
+#include "base/android/content_uri_utils.h"
+#include "base/files/file_util.h"
+#include "base/path_service.h"
+#include "base/test/test_file_util.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace base {
+namespace android {
+
+TEST(ContentUriUtilsTest, ContentUriMimeTest) {
+  // Get the test image path.
+  FilePath data_dir;
+  ASSERT_TRUE(PathService::Get(DIR_TEST_DATA, &data_dir));
+  data_dir = data_dir.AppendASCII("file_util");
+  ASSERT_TRUE(PathExists(data_dir));
+  FilePath image_file = data_dir.Append(FILE_PATH_LITERAL("red.png"));
+
+  // Insert the image into MediaStore. MediaStore will do some conversions, and
+  // return the content URI.
+  FilePath path = base::InsertImageIntoMediaStore(image_file);
+  EXPECT_TRUE(path.IsContentUri());
+  EXPECT_TRUE(PathExists(path));
+
+  std::string mime = GetContentUriMimeType(path);
+  EXPECT_EQ(mime, std::string("image/png"));
+
+  FilePath invalid_path("content://foo.bar");
+  mime = GetContentUriMimeType(invalid_path);
+  EXPECT_TRUE(mime.empty());
+}
+
+}  // namespace android
+}  // namespace base
diff --git a/base/android/java/src/org/chromium/base/ContentUriUtils.java b/base/android/java/src/org/chromium/base/ContentUriUtils.java
index 70c27ed..ef527e1 100644
--- a/base/android/java/src/org/chromium/base/ContentUriUtils.java
+++ b/base/android/java/src/org/chromium/base/ContentUriUtils.java
@@ -12,6 +12,7 @@ import android.os.ParcelFileDescriptor;
 import android.util.Log;
 
 import java.io.File;
+import java.io.FileNotFoundException;
 
 /**
  * This class provides methods to access content URI schemes.
@@ -26,11 +27,11 @@ public abstract class ContentUriUtils {
      */
     public interface FileProviderUtil {
         /**
-         * Generate a content uri from the given file.
+         * Generate a content URI from the given file.
          * @param context Application context.
          * @param file The file to be translated.
          */
-        public Uri getContentUriFromFile(Context context, File file);
+        Uri getContentUriFromFile(Context context, File file);
     }
 
     // Prevent instantiation.
@@ -54,7 +55,7 @@ public abstract class ContentUriUtils {
      *
      * @param context {@link Context} in interest
      * @param uriString the content URI to open
-     * @returns file desciptor upon sucess, or -1 otherwise.
+     * @return file desciptor upon sucess, or -1 otherwise.
      */
     @CalledByNative
     public static int openContentUriForRead(Context context, String uriString) {
@@ -70,23 +71,34 @@ public abstract class ContentUriUtils {
      *
      * @param context {@link Context} in interest.
      * @param uriString the content URI to query.
-     * @returns true if the uri exists, or false otherwise.
+     * @return true if the URI exists, or false otherwise.
      */
     @CalledByNative
     public static boolean contentUriExists(Context context, String uriString) {
-        ParcelFileDescriptor pfd = getParcelFileDescriptor(context, uriString);
-        if (pfd == null) {
-            return false;
-        }
-        return true;
+        return getParcelFileDescriptor(context, uriString) != null;
+    }
+
+    /**
+     * Retrieve the MIME type for the content URI.
+     *
+     * @param context {@link Context} in interest.
+     * @param uriString the content URI to look up.
+     * @return MIME type or null if the input params are empty or invalid.
+     */
+    @CalledByNative
+    public static String getMimeType(Context context, String uriString) {
+        ContentResolver resolver = context.getContentResolver();
+        if (resolver == null) return null;
+        Uri uri = Uri.parse(uriString);
+        return resolver.getType(uri);
     }
 
     /**
-     * Helper method to open a content URI and return the ParcelFileDescriptor.
+     * Helper method to open a content URI and returns the ParcelFileDescriptor.
      *
      * @param context {@link Context} in interest.
      * @param uriString the content URI to open.
-     * @returns ParcelFileDescriptor of the content URI, or NULL if the file does not exist.
+     * @return ParcelFileDescriptor of the content URI, or NULL if the file does not exist.
      */
     private static ParcelFileDescriptor getParcelFileDescriptor(Context context, String uriString) {
         ContentResolver resolver = context.getContentResolver();
@@ -95,8 +107,12 @@ public abstract class ContentUriUtils {
         ParcelFileDescriptor pfd = null;
         try {
             pfd = resolver.openFileDescriptor(uri, "r");
-        } catch (java.io.FileNotFoundException e) {
+        } catch (FileNotFoundException e) {
             Log.w(TAG, "Cannot find content uri: " + uriString, e);
+        } catch (SecurityException e) {
+            Log.w(TAG, "Cannot open content uri: " + uriString, e);
+        } catch (IllegalArgumentException e) {
+            Log.w(TAG, "Unknown content uri: " + uriString, e);
         }
         return pfd;
     }
@@ -107,7 +123,7 @@ public abstract class ContentUriUtils {
      * @param uri the content URI to be resolved.
      * @param contentResolver the content resolver to query.
      * @param columnField the column field to query.
-     * @returns the display name of the @code uri if present in the database
+     * @return the display name of the @code uri if present in the database
      *  or an empty string otherwise.
      */
     public static String getDisplayName(