Revert of Changes caching logic of mojo java apps

mojo/runner/android/apk/src/org/chromium/mojo/shell/FileHelper.java

Index: mojo/runner/android/apk/src/org/chromium/mojo/shell/FileHelper.java
diff --git a/mojo/runner/android/apk/src/org/chromium/mojo/shell/FileHelper.java b/mojo/runner/android/apk/src/org/chromium/mojo/shell/FileHelper.java
index c41f24f164cc568aa675e4b19175f1cae226bf11..08455528fde18f59ebc3ef2162d4ba34f56f957e 100644
--- a/mojo/runner/android/apk/src/org/chromium/mojo/shell/FileHelper.java
+++ b/mojo/runner/android/apk/src/org/chromium/mojo/shell/FileHelper.java
@@ -7,8 +7,7 @@
 import android.content.Context;
 import android.content.pm.PackageInfo;
 import android.content.pm.PackageManager;
-
-import org.chromium.base.Log;
+import android.util.Log;
 
 import java.io.BufferedInputStream;
 import java.io.BufferedOutputStream;
@@ -16,6 +15,7 @@
 import java.io.FileInputStream;
 import java.io.FileNotFoundException;
 import java.io.FileOutputStream;
+import java.io.FilenameFilter;
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.OutputStream;
@@ -36,87 +36,62 @@
     private static final String TIMESTAMP_PREFIX = "asset_timestamp-";
 
     /**
-     * Used to indicate the type of destination file that should be created.
-     */
-    public enum FileType {
-        TEMPORARY,
-        PERMANENT,
-    }
-
-    public enum ArchiveType {
-        /**
-         * The archive was created for a content handler (contains the mojo escape sequence).
-         */
-        CONTENT_HANDLER,
-        NORMAL,
-    }
-
-    /**
      * Looks for a timestamp file on disk that indicates the version of the APK that the resource
      * assets were extracted from. Returns null if a timestamp was found and it indicates that the
-     * resources match the current APK. Otherwise returns the file to create.
+     * resources match the current APK. Otherwise returns a String that represents the filename of a
+     * timestamp to create.
      */
-    private static File findAssetTimestamp(Context context, File outputDir) {
+    private static String checkAssetTimestamp(Context context, File outputDir) {
         PackageManager pm = context.getPackageManager();
         PackageInfo pi = null;
 
         try {
             pi = pm.getPackageInfo(context.getPackageName(), 0);
         } catch (PackageManager.NameNotFoundException e) {
+            return TIMESTAMP_PREFIX;
         }
 
         if (pi == null) {
-            return new File(outputDir, TIMESTAMP_PREFIX);
+            return TIMESTAMP_PREFIX;
         }
 
-        final File expectedTimestamp =
-                new File(outputDir, TIMESTAMP_PREFIX + pi.versionCode + "-" + pi.lastUpdateTime);
-        return expectedTimestamp.exists() ? null : expectedTimestamp;
-    }
+        String expectedTimestamp = TIMESTAMP_PREFIX + pi.versionCode + "-" + pi.lastUpdateTime;
 
-    /**
-     * Invoke prior to extracting any assets into {@code directory}. If necessary deletes all the
-     * files in the specified directory. The return value must be supplied to {@link
-     *createTimestampIfNecessary}.
-     *
-     * @param directory directory assets will be extracted to
-     * @return non-null if a file with the specified name needs to be created after assets have
-     * been extracted.
-     */
-    public static File prepareDirectoryForAssets(Context context, File directory) {
-        final File timestamp = findAssetTimestamp(context, directory);
-        if (timestamp == null) {
-            return null;
+        String[] timestamps = outputDir.list(new FilenameFilter() {
+            @Override
+            public boolean accept(File dir, String name) {
+                return name.startsWith(TIMESTAMP_PREFIX);
+            }
+        });
+
+        if (timestamps.length != 1) {
+            // If there's no timestamp, nuke to be safe as we can't tell the age of the files.
+            // If there's multiple timestamps, something's gone wrong so nuke.
+            return expectedTimestamp;
         }
-        for (File child : directory.listFiles()) {
-            deleteRecursively(child);
+
+        if (!expectedTimestamp.equals(timestamps[0])) {
+            return expectedTimestamp;
         }
-        return timestamp;
-    }
 
-    /**
-     * Creates a file used as a timestamp. The supplied file comes from {@link
-     *prepareDirectoryForAssets}.
-     *
-     * @param timestamp path of file to create, or null if a file does not need to be created
-     */
-    public static void createTimestampIfNecessary(File timestamp) {
-        if (timestamp == null) {
-            return;
-        }
-        try {
-            timestamp.createNewFile();
-        } catch (IOException e) {
-            // In the worst case we don't write a timestamp, so we'll re-extract the asset next
-            // time.
-            Log.w(TAG, "Failed to write asset timestamp!");
-        }
+        // Timestamp file is already up-to date.
+        return null;
     }
 
     public static File extractFromAssets(Context context, String assetName, File outputDirectory,
-            FileType fileType) throws IOException, FileNotFoundException {
+            boolean useTempFile) throws IOException, FileNotFoundException {
+        String timestampToCreate = null;
+        if (!useTempFile) {
+            timestampToCreate = checkAssetTimestamp(context, outputDirectory);
+            if (timestampToCreate != null) {
+                for (File child : outputDirectory.listFiles()) {
+                    deleteRecursively(child);
+                }
+            }
+        }
+
         File outputFile;
-        if (fileType == FileType.TEMPORARY) {
+        if (useTempFile) {
             // Make the original filename part of the temp file name.
             // TODO(ppi): do we need to sanitize the suffix?
             String suffix = "-" + assetName;
@@ -136,48 +111,36 @@
         } finally {
             inputStream.close();
         }
+
+        if (timestampToCreate != null) {
+            try {
+                new File(outputDirectory, timestampToCreate).createNewFile();
+            } catch (IOException e) {
+                // In the worst case we don't write a timestamp, so we'll re-extract the asset next
+                // time.
+                Log.w(TAG, "Failed to write asset timestamp!");
+            }
+        }
+
         return outputFile;
     }
 
     /**
      * Extracts the file of the given extension from the archive. Throws FileNotFoundException if no
      * matching file is found.
-     *
-     * @return path of extracted file
      */
-    static File extractFromArchive(File archive, String suffixToMatch, File outputDirectory,
-            FileType fileType, ArchiveType archiveType) throws IOException, FileNotFoundException {
-        if (!outputDirectory.exists() && !outputDirectory.mkdirs()) {
-            Log.e(TAG, "extractFromArchive unable to create directory "
-                            + outputDirectory.getAbsolutePath());
-            throw new FileNotFoundException();
-        }
-
-        BufferedInputStream inputStream = new BufferedInputStream(new FileInputStream(archive));
-        if (archiveType == ArchiveType.CONTENT_HANDLER) {
-            int currentChar;
-            do {
-                currentChar = inputStream.read();
-            } while (currentChar != -1 && currentChar != '\n');
-            if (currentChar == -1) {
-                throw new FileNotFoundException();
-            }
-            inputStream = new BufferedInputStream(inputStream);
-        }
-        ZipInputStream zip = new ZipInputStream(inputStream);
+    static File extractFromArchive(File archive, String suffixToMatch,
+            File outputDirectory) throws IOException, FileNotFoundException {
+        ZipInputStream zip = new ZipInputStream(new BufferedInputStream(new FileInputStream(
+                archive)));
         ZipEntry entry;
         while ((entry = zip.getNextEntry()) != null) {
             if (entry.getName().endsWith(suffixToMatch)) {
-                // TODO(sky): sanitize name.
-                final String name = new File(entry.getName()).getName();
-                File extractedFile;
                 // Make the original filename part of the temp file name.
-                if (fileType == FileType.TEMPORARY) {
-                    final String suffix = "-" + name;
-                    extractedFile = File.createTempFile(TEMP_FILE_PREFIX, suffix, outputDirectory);
-                } else {
-                    extractedFile = new File(outputDirectory, name);
-                }
+                // TODO(ppi): do we need to sanitize the suffix?
+                String suffix = "-" + new File(entry.getName()).getName();
+                File extractedFile = File.createTempFile(TEMP_FILE_PREFIX, suffix,
+                        outputDirectory);
                 writeStreamToFile(zip, extractedFile);
                 zip.close();
                 return extractedFile;