AI 146085: Extract mini-thumb handling code to a separate class.

Automated import of CL 146085

3 files changed, 216 insertions, 200 deletions

diff --git a/src/com/android/camera/gallery/BaseImage.java b/src/com/android/camera/gallery/BaseImage.java
index 85fa102..f11cc26 100644
--- a/src/com/android/camera/gallery/BaseImage.java
+++ b/src/com/android/camera/gallery/BaseImage.java
@@ -44,8 +44,8 @@ public abstract class BaseImage implements IImage {
     private static final boolean VERBOSE = false;
     private static final String TAG = "BaseImage";
 
-    static final int BYTES_PER_MINTHUMB = 10000;
-    private static final byte [] sMiniThumbData = new byte[BYTES_PER_MINTHUMB];
+    private static final byte [] sMiniThumbData =
+            new byte[MiniThumbFile.BYTES_PER_MINTHUMB];
 
     protected ContentResolver mContentResolver;
     protected long mId, mMiniThumbMagic;
diff --git a/src/com/android/camera/gallery/BaseImageList.java b/src/com/android/camera/gallery/BaseImageList.java
index 0b5e33b..49b43d3 100644
--- a/src/com/android/camera/gallery/BaseImageList.java
+++ b/src/com/android/camera/gallery/BaseImageList.java
@@ -26,25 +26,20 @@ import android.database.Cursor;
 import android.graphics.Bitmap;
 import android.graphics.BitmapFactory;
 import android.net.Uri;
-import android.os.Environment;
-import android.os.Handler;
 import android.os.ParcelFileDescriptor;
 import android.provider.BaseColumns;
 import android.provider.MediaStore.Images;
-import android.provider.MediaStore.MediaColumns;
 import android.provider.MediaStore.Images.ImageColumns;
 import android.provider.MediaStore.Images.Thumbnails;
+import android.provider.MediaStore.MediaColumns;
 import android.util.Log;
 
 import com.android.camera.ExifInterface;
 import com.android.camera.ImageManager;
 
-import java.io.File;
 import java.io.FileNotFoundException;
 import java.io.IOException;
 import java.io.OutputStream;
-import java.io.RandomAccessFile;
-import java.util.ArrayList;
 import java.util.HashMap;
 
 /**
@@ -108,7 +103,7 @@ public abstract class BaseImageList implements IImageList {
     protected Context mContext;
     protected Uri mUri;
     protected HashMap<Long, IImage> mCache = new HashMap<Long, IImage>();
-    protected RandomAccessFile mMiniThumbFile;
+    protected MiniThumbFile mMiniThumbFile;
     protected Uri mThumbUri;
 
     public BaseImageList(Context ctx, ContentResolver cr, Uri uri, int sort,
@@ -119,34 +114,7 @@ public abstract class BaseImageList implements IImageList {
         mBaseUri = uri;
         mBucketId = bucketId;
         mContentResolver = cr;
-    }
-
-    String randomAccessFilePath(int version) {
-        String directoryName =
-                Environment.getExternalStorageDirectory().toString()
-                + "/DCIM/.thumbnails";
-        return directoryName + "/.thumbdata" + version + "-" + mUri.hashCode();
-    }
-
-    RandomAccessFile miniThumbDataFile() {
-        if (mMiniThumbFile == null) {
-            String path = randomAccessFilePath(MINI_THUMB_DATA_FILE_VERSION);
-            File directory = new File(new File(path).getParent());
-            if (!directory.isDirectory()) {
-                if (!directory.mkdirs()) {
-                    Log.e(TAG, "!!!! unable to create .thumbnails directory "
-                            + directory.toString());
-                }
-            }
-            File f = new File(path);
-            if (VERBOSE) Log.v(TAG, "file f is " + f.toString());
-            try {
-                mMiniThumbFile = new RandomAccessFile(f, "rw");
-            } catch (IOException ex) {
-                // ignore exception
-            }
-        }
-        return mMiniThumbFile;
+        mMiniThumbFile = new MiniThumbFile(uri);
     }
 
     /**
@@ -312,11 +280,10 @@ public abstract class BaseImageList implements IImageList {
      */
     public long checkThumbnail(BaseImage existingImage, Cursor c, int i,
             byte[][] createdThumbnailData) throws IOException {
-        long magic, fileMagic = 0, id;
+        long magic, id;
         if (BitmapManager.instance().acquireResourceLock() == false) {
             return -1;
         }
-        Log.v(TAG, "checkThumbnail: i="+i);
         
         try {
             if (existingImage == null) {
@@ -336,35 +303,9 @@ public abstract class BaseImageList implements IImageList {
             }
 
             if (magic != 0) {
-                // check the mini thumb file for the right data.  Right is
-                // defined as having the right magic number at the offset
-                // reserved for this "id".
-                RandomAccessFile r = miniThumbDataFile();
-                if (r != null) {
-                    synchronized (r) {
-                        long pos = id * BaseImage.BYTES_PER_MINTHUMB;
-                        try {
-                            // check that we can read the following 9 bytes
-                            // (1 for the "status" and 8 for the long)
-                            if (r.length() >= pos + 1 + 8) {
-                                r.seek(pos);
-                                if (r.readByte() == 1) {
-                                    fileMagic = r.readLong();
-                                    if (fileMagic == magic && magic != 0
-                                            && magic != id) {
-                                        return magic;
-                                    }
-                                }
-                            }
-                        } catch (IOException ex) {
-                            Log.v(TAG, "got exception checking file magic: "
-                                    + ex);
-                        }
-                    }
-                }
-                if (VERBOSE) {
-                    Log.v(TAG, "didn't verify... fileMagic: " + fileMagic
-                            + "; magic: " + magic + "; id: " + id + "; ");
+                long fileMagic = mMiniThumbFile.getMagic(id);
+                if (fileMagic == magic && magic != 0 && magic != id) {
+                    return magic;
                 }
             }
 
@@ -414,7 +355,6 @@ public abstract class BaseImageList implements IImageList {
             }
 
             synchronized (c) {
-                Log.v(TAG, "checkThumbnail: moveToPosition i="+i);
                 c.moveToPosition(i);
                 c.updateLong(indexMiniThumbId(), magic);
                 c.commitUpdates();
@@ -451,16 +391,6 @@ public abstract class BaseImageList implements IImageList {
             return;
         }
 
-        String oldPath = randomAccessFilePath(MINI_THUMB_DATA_FILE_VERSION - 1);
-        File oldFile = new File(oldPath);
-
-        if (count == 0) {
-            // now check that we have the right thumbs file
-            if (!oldFile.exists()) {
-                return;
-            }
-        }
-
         c = getCursor();
         try {
             if (VERBOSE) Log.v(TAG, "checkThumbnails found " + c.getCount());
@@ -488,11 +418,6 @@ public abstract class BaseImageList implements IImageList {
                 Log.v(TAG, "checkThumbnails existing after reaching count "
                         + c.getCount());
             }
-            try {
-                oldFile.delete();
-            } catch (SecurityException ex) {
-                // ignore
-            }
         }
     }
 
@@ -531,14 +456,7 @@ public abstract class BaseImageList implements IImageList {
             // IllegalStateException may be thrown if the cursor is stale.
             Log.e(TAG, "Caught exception while deactivating cursor.", e);
         }
-        if (mMiniThumbFile != null) {
-            try {
-                mMiniThumbFile.close();
-                mMiniThumbFile = null;
-            } catch (IOException ex) {
-                // ignore exception
-            }
-        }
+        mMiniThumbFile.deactivate();
     }
 
     public void dump(String msg) {
@@ -633,60 +551,17 @@ public abstract class BaseImageList implements IImageList {
     }
 
     byte [] getMiniThumbFromFile(long id, byte [] data, long magicCheck) {
-        RandomAccessFile r = miniThumbDataFile();
-        if (r == null) return null;
-
-        long pos = id * BaseImage.BYTES_PER_MINTHUMB;
-        synchronized (r) {
-            try {
-                r.seek(pos);
-                if (r.readByte() == 1) {
-                    long magic = r.readLong();
-                    if (magic != magicCheck) {
-                        if (VERBOSE) {
-                            Log.v(TAG, "for id " + id + "; magic: " + magic
-                                    + "; magicCheck: " + magicCheck
-                                    + " (fail)");
-                        }
-                        return null;
-                    }
-                    int length = r.readInt();
-                    r.read(data, 0, length);
-                    return data;
-                } else {
-                    return null;
-                }
-            } catch (IOException ex) {
-                long fileLength;
-                try {
-                    fileLength = r.length();
-                } catch (IOException ex1) {
-                    fileLength = -1;
-                }
-                if (VERBOSE) {
-                    Log.e(TAG, "couldn't read thumbnail for " + id + "; "
-                            + ex.toString() + "; pos is " + pos + "; length is "
-                            + fileLength);
-                }
-                return null;
-            }
-        }
+        return mMiniThumbFile.getMiniThumbFromFile(id, data, magicCheck);
     }
-    protected int getRowFor(IImage imageObj) {
-        Cursor c = getCursor();
-        synchronized (c) {
-            int index = 0;
-            long targetId = imageObj.fullSizeImageId();
-            if (c.moveToFirst()) {
-                do {
-                    if (c.getLong(0) == targetId) {
-                        return index;
-                    }
-                    index += 1;
-                } while (c.moveToNext());
-            }
-            return -1;
-        }
+    
+    void saveMiniThumbToFile(Bitmap bitmap, long id, long magic)       
+            throws IOException {
+        mMiniThumbFile.saveMiniThumbToFile(bitmap, id, magic);
+    } 
+            
+    void saveMiniThumbToFile(byte[] data, long id, long magic)
+            throws IOException {
+        mMiniThumbFile.saveMiniThumbToFile(data, id, magic);
     }
 
     protected abstract int indexOrientation();
@@ -773,59 +648,4 @@ public abstract class BaseImageList implements IImageList {
         mCursor.requery();
         mCursorDeactivated = false;
     }
-
-    protected void saveMiniThumbToFile(Bitmap bitmap, long id, long magic)
-            throws IOException {
-        byte[] data = Util.miniThumbData(bitmap);
-        saveMiniThumbToFile(data, id, magic);
-    }
-
-    protected void saveMiniThumbToFile(byte[] data, long id, long magic)
-            throws IOException {
-        RandomAccessFile r = miniThumbDataFile();
-        if (r == null) return;
-
-        long pos = id * BaseImage.BYTES_PER_MINTHUMB;
-        long t0 = System.currentTimeMillis();
-        synchronized (r) {
-            try {
-                long t1 = System.currentTimeMillis();
-                long t2 = System.currentTimeMillis();
-                if (data != null) {
-                    if (data.length > BaseImage.BYTES_PER_MINTHUMB) {
-                        if (VERBOSE) {
-                            Log.v(TAG, "warning: " + data.length + " > "
-                                    + BaseImage.BYTES_PER_MINTHUMB);
-                        }
-                        return;
-                    }
-                    r.seek(pos);
-                    r.writeByte(0);     // we have no data in this slot
-
-                    // if magic is 0 then leave it alone
-                    if (magic == 0) {
-                        r.skipBytes(8);
-                    } else {
-                        r.writeLong(magic);
-                    }
-                    r.writeInt(data.length);
-                    r.write(data);
-                    //                      f.flush();
-                    r.seek(pos);
-                    r.writeByte(1);  // we have data in this slot
-                    long t3 = System.currentTimeMillis();
-
-                    if (VERBOSE) {
-                        Log.v(TAG, "saveMiniThumbToFile took " + (t3 - t0)
-                                + "; " + (t1 - t0) + " " + (t2 - t1) + " "
-                                + (t3 - t2));
-                    }
-                }
-            } catch (IOException ex) {
-                Log.e(TAG, "couldn't save mini thumbnail data for "
-                        + id + "; " + ex.toString());
-                throw ex;
-            }
-        }
-    }
 }
diff --git a/src/com/android/camera/gallery/MiniThumbFile.java b/src/com/android/camera/gallery/MiniThumbFile.java
new file mode 100644
index 0000000..e2c825c
--- /dev/null
+++ b/src/com/android/camera/gallery/MiniThumbFile.java
@@ -0,0 +1,196 @@
+/*
+ * Copyright (C) 2009 The Android Open Source Project
+ *
+ * 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.android.camera.gallery;
+
+import android.graphics.Bitmap;
+import android.net.Uri;               
+import android.os.Environment;
+import android.util.Log;
+
+import java.io.File;
+import java.io.IOException;
+import java.io.RandomAccessFile;
+
+// This class handles the mini-thumb file. A mini-thumb file consists
+// of blocks, indexed by id. Each block has BYTES_PER_MINTHUMB bytes in the
+// following format:
+//
+// 1 byte status (0 = empty, 1 = mini-thumb available)
+// 8 bytes magic (a magic number to match what's in the database)
+// 4 bytes data length (LEN)
+// LEN bytes jpeg data
+// (the remaining bytes are unused)
+//
+class MiniThumbFile {
+    private static final String TAG = "MiniThumbFile";
+    private static final int MINI_THUMB_DATA_FILE_VERSION = 3;
+    public static final int BYTES_PER_MINTHUMB = 10000;
+    private static final int HEADER_SIZE = 1 + 8 + 4;
+    private static final byte [] sMiniThumbData = new byte[BYTES_PER_MINTHUMB];
+    private Uri mUri;
+    private RandomAccessFile mMiniThumbFile;                           
+    
+    private String randomAccessFilePath(int version) {
+        String directoryName =
+                Environment.getExternalStorageDirectory().toString()
+                + "/DCIM/.thumbnails";
+        return directoryName + "/.thumbdata" + version + "-" + mUri.hashCode();
+    }
+
+    private void removeOldFile() {
+        String oldPath = randomAccessFilePath(MINI_THUMB_DATA_FILE_VERSION - 1);
+        File oldFile = new File(oldPath);
+        if (!oldFile.exists()) {
+            try {
+                oldFile.delete();
+            } catch (SecurityException ex) {
+                // ignore
+            }
+        }
+    }
+
+    private RandomAccessFile miniThumbDataFile() {
+        if (mMiniThumbFile == null) {
+            removeOldFile();
+            String path = randomAccessFilePath(MINI_THUMB_DATA_FILE_VERSION);
+            File directory = new File(path).getParentFile();
+            if (!directory.isDirectory()) {
+                if (!directory.mkdirs()) {
+                    Log.e(TAG, "Unable to create .thumbnails directory "
+                            + directory.toString());
+                }
+            }
+            File f = new File(path);
+            try {
+                mMiniThumbFile = new RandomAccessFile(f, "rw");
+            } catch (IOException ex) {
+                // ignore exception
+            }
+        }
+        return mMiniThumbFile;
+    }
+
+    public MiniThumbFile(Uri uri) {
+        mUri = uri;
+    }
+
+    public void deactivate() {
+        if (mMiniThumbFile != null) {
+            try {
+                mMiniThumbFile.close();
+                mMiniThumbFile = null;
+            } catch (IOException ex) {
+                // ignore exception
+            }
+        }
+    }
+
+    // Get the magic number for the specified id in the mini-thumb file.
+    // Returns 0 if the magic is not available.
+    public long getMagic(long id) {
+        // check the mini thumb file for the right data.  Right is
+        // defined as having the right magic number at the offset
+        // reserved for this "id".
+        RandomAccessFile r = miniThumbDataFile();
+        if (r != null) {
+            synchronized (r) {
+                long pos = id * BYTES_PER_MINTHUMB;
+                try {
+                    // check that we can read the following 9 bytes
+                    // (1 for the "status" and 8 for the long)
+                    if (r.length() >= pos + 1 + 8) {
+                        r.seek(pos);
+                        if (r.readByte() == 1) {
+                            long fileMagic = r.readLong();
+                            return fileMagic;
+                        }
+                    }
+                } catch (IOException ex) {
+                    Log.v(TAG, "Got exception checking file magic: ", ex);
+                }
+            }
+        }
+        return 0;
+    }
+
+    public void saveMiniThumbToFile(Bitmap bitmap, long id, long magic)
+            throws IOException {
+        byte[] data = Util.miniThumbData(bitmap);
+        saveMiniThumbToFile(data, id, magic);
+    }
+
+    public void saveMiniThumbToFile(byte[] data, long id, long magic)
+            throws IOException {
+        RandomAccessFile r = miniThumbDataFile();
+        if (r == null) return;
+
+        long pos = id * BYTES_PER_MINTHUMB;
+        long t0 = System.currentTimeMillis();
+        synchronized (r) {
+            try {
+                if (data != null) {
+                    if (data.length > BYTES_PER_MINTHUMB - HEADER_SIZE) {
+                        // not enough space to store it.
+                        return;
+                    }
+                    r.seek(pos);
+                    r.writeByte(0);     // we have no data in this slot
+
+                    // if magic is 0 then leave it alone
+                    if (magic == 0) {
+                        r.skipBytes(8);
+                    } else {
+                        r.writeLong(magic);
+                    }
+                    r.writeInt(data.length);
+                    r.write(data);
+                    r.seek(pos);
+                    r.writeByte(1);  // we have data in this slot
+                }
+            } catch (IOException ex) {
+                Log.e(TAG, "couldn't save mini thumbnail data for "
+                        + id + "; ", ex);
+                throw ex;
+            }
+        }
+    }
+
+    byte [] getMiniThumbFromFile(long id, byte [] data, long magicCheck) {
+        RandomAccessFile r = miniThumbDataFile();
+        if (r == null) return null;
+
+        long pos = id * BYTES_PER_MINTHUMB;
+        synchronized (r) {
+            try {
+                r.seek(pos);
+                if (r.readByte() == 1) {
+                    long magic = r.readLong();
+                    if (magic != magicCheck) {
+                        return null;
+                    }
+                    int length = r.readInt();
+                    r.read(data, 0, length);
+                    return data;
+                } else {
+                    return null;
+                }
+            } catch (IOException ex) {
+                return null;
+            }
+        }
+    }
+}