Add checkstyle plugin and and fix style issues.

4 files changed, 254 insertions, 223 deletions

diff --git a/third_party/gif_decoder/src/main/java/com/bumptech/glide/gifdecoder/GifDecoder.java b/third_party/gif_decoder/src/main/java/com/bumptech/glide/gifdecoder/GifDecoder.java
index 2381a7a6..4d653cb5 100644
--- a/third_party/gif_decoder/src/main/java/com/bumptech/glide/gifdecoder/GifDecoder.java
+++ b/third_party/gif_decoder/src/main/java/com/bumptech/glide/gifdecoder/GifDecoder.java
@@ -59,7 +59,7 @@ public class GifDecoder {
      */
     public static final int STATUS_OK = 0;
     /**
-     * File read status: Error decoding file (may be partially decoded)
+     * File read status: Error decoding file (may be partially decoded).
      */
     public static final int STATUS_FORMAT_ERROR = 1;
     /**
@@ -67,36 +67,37 @@ public class GifDecoder {
      */
     public static final int STATUS_OPEN_ERROR = 2;
     /**
-     * max decoder pixel stack size
+     * max decoder pixel stack size.
      */
     private static final int MAX_STACK_SIZE = 4096;
 
     /**
-     * GIF Disposal Method meaning take no action
+     * GIF Disposal Method meaning take no action.
      */
     private static final int DISPOSAL_UNSPECIFIED = 0;
     /**
-     * GIF Disposal Method meaning leave canvas from previous frame
+     * GIF Disposal Method meaning leave canvas from previous frame.
      */
-    private static final int DISPOSAL_NONE = 1;
+//    private static final int DISPOSAL_NONE = 1;
     /**
-     * GIF Disposal Method meaning clear canvas to background color
+     * GIF Disposal Method meaning clear canvas to background color.
      */
     private static final int DISPOSAL_BACKGROUND = 2;
     /**
-     * GIF Disposal Method meaning clear canvas to frame before last
+     * GIF Disposal Method meaning clear canvas to frame before last.
      */
-    private static final int DISPOSAL_PREVIOUS = 3;
+//    private static final int DISPOSAL_PREVIOUS = 3;
 
-    //Global File Header values and parsing flags
-    private int[] act; // active color table
+    // Global File Header values and parsing flags.
+    // Active color table.
+    private int[] act;
 
-    // Raw GIF data from input source
+    // Raw GIF data from input source.
     private ByteBuffer rawData;
 
-    // Raw data read working array
-    private byte[] block = new byte[256]; // current data block
-    // LZW decoder working arrays
+    // Raw data read working array.
+    private byte[] block = new byte[256];
+    // LZW decoder working arrays.
     private short[] prefix;
     private byte[] suffix;
     private byte[] pixelStack;
@@ -130,10 +131,6 @@ public class GifDecoder {
         return header.isTransparent;
     }
 
-    public int getGifByteSize() {
-        return data.length;
-    }
-
     public byte[] getData() {
         return data;
     }
@@ -144,7 +141,7 @@ public class GifDecoder {
     }
 
     /**
-     * Move the animation frame counter forward
+     * Move the animation frame counter forward.
      */
     public void advance() {
         framePointer = (framePointer + 1) % header.frameCount;
@@ -153,8 +150,8 @@ public class GifDecoder {
     /**
      * Gets display duration for specified frame.
      *
-     * @param n int index of frame
-     * @return delay in milliseconds
+     * @param n int index of frame.
+     * @return delay in milliseconds.
      */
     public int getDelay(int n) {
         int delay = -1;
@@ -165,7 +162,7 @@ public class GifDecoder {
     }
 
     /**
-     * Gets display duration for the upcoming frame
+     * Gets display duration for the upcoming frame.
      */
     public int getNextDelay() {
         if (header.frameCount <= 0 || framePointer < 0) {
@@ -178,23 +175,23 @@ public class GifDecoder {
     /**
      * Gets the number of frames read from file.
      *
-     * @return frame count
+     * @return frame count.
      */
     public int getFrameCount() {
         return header.frameCount;
     }
 
     /**
-     * Gets the current index of the animation frame, or -1 if animation hasn't not yet started
+     * Gets the current index of the animation frame, or -1 if animation hasn't not yet started.
      *
-     * @return frame index
+     * @return frame index.
      */
     public int getCurrentFrameIndex() {
         return framePointer;
     }
 
     /**
-     * Gets the "Netscape" iteration count, if any. A count of 0 means repeat indefinitiely.
+     * Gets the "Netscape" iteration count, if any. A count of 0 means repeat indefinitely.
      *
      * @return iteration count if one was specified, else 1.
      */
@@ -209,16 +206,16 @@ public class GifDecoder {
     /**
      * Get the next frame in the animation sequence.
      *
-     * @return Bitmap representation of frame
+     * @return Bitmap representation of frame.
      */
     public Bitmap getNextFrame() {
-        if (header.frameCount <= 0 || framePointer < 0 ) {
+        if (header.frameCount <= 0 || framePointer < 0) {
             return null;
         }
 
         GifFrame frame = header.frames.get(framePointer);
 
-        //Set the appropriate color table
+        // Set the appropriate color table.
         if (frame.lct == null) {
             act = header.gct;
         } else {
@@ -231,15 +228,18 @@ public class GifDecoder {
         int save = 0;
         if (frame.transparency) {
             save = act[frame.transIndex];
-            act[frame.transIndex] = 0; // set transparent color if specified
+            // Set transparent color if specified.
+            act[frame.transIndex] = 0;
         }
         if (act == null) {
             Log.w(TAG, "No Valid Color Table");
-            header.status = STATUS_FORMAT_ERROR; // no color table defined
+            // No color table defined.
+            header.status = STATUS_FORMAT_ERROR;
             return null;
         }
 
-        Bitmap result = setPixels(framePointer); // transfer pixel data to image
+        // Transfer pixel data to image.
+        Bitmap result = setPixels(framePointer);
 
         // Reset the transparent pixel in the color table
         if (frame.transparency) {
@@ -250,10 +250,10 @@ public class GifDecoder {
     }
 
     /**
-     * Reads GIF image from stream
+     * Reads GIF image from stream.
      *
      * @param is containing GIF file.
-     * @return read status code (0 = no errors)
+     * @return read status code (0 = no errors).
      */
     public int read(InputStream is, int contentLength) {
         if (is != null) {
@@ -290,32 +290,32 @@ public class GifDecoder {
         this.id = id;
         this.header = header;
         this.data = data;
-        //Initialize the raw data buffer
+        // Initialize the raw data buffer.
         rawData = ByteBuffer.wrap(data);
         rawData.rewind();
         rawData.order(ByteOrder.LITTLE_ENDIAN);
 
-        //Now that we know the size, init scratch arrays
+        // Now that we know the size, init scratch arrays.
         mainPixels = new byte[header.width * header.height];
         mainScratch = new int[header.width * header.height];
     }
 
     /**
-     * Reads GIF image from byte array
+     * Reads GIF image from byte array.
      *
      * @param data containing GIF file.
-     * @return read status code (0 = no errors)
+     * @return read status code (0 = no errors).
      */
     public int read(byte[] data) {
         this.data = data;
         this.header = new GifHeaderParser(data).parseHeader();
         if (data != null) {
-            //Initialize the raw data buffer
+            // Initialize the raw data buffer.
             rawData = ByteBuffer.wrap(data);
             rawData.rewind();
             rawData.order(ByteOrder.LITTLE_ENDIAN);
 
-            //Now that we know the size, init scratch arrays
+            // Now that we know the size, init scratch arrays.
             mainPixels = new byte[header.width * header.height];
             mainScratch = new int[header.width * header.height];
         }
@@ -334,16 +334,11 @@ public class GifDecoder {
             previousFrame = header.frames.get(previousIndex);
         }
 
-        // final location of blended pixels
+        // Final location of blended pixels.
         final int[] dest = mainScratch;
 
-        // fill in starting image contents based on last image's dispose code
+        // Fill in starting image contents based on last image's dispose code.
         if (previousFrame != null && previousFrame.dispose > DISPOSAL_UNSPECIFIED) {
-//            if (previousFrame.dispose == DISPOSAL_NONE) {
-//                We don't need to do anything for this case, mainScratch should already have the pixels of the
-//                previous image.
-//                currentImage.getPixels(dest, 0, header.width, 0, 0, header.width, header.height);
-//            }
             if (previousFrame.dispose == DISPOSAL_BACKGROUND) {
                 // Start with a canvas filled with the background color
                 int c = 0;
@@ -368,10 +363,10 @@ public class GifDecoder {
             }
         }
 
-        // Decode pixels for this frame  into the global pixels[] scratch
-        decodeBitmapData(currentFrame, mainPixels); // decode pixel data
+        // Decode pixels for this frame  into the global pixels[] scratch.
+        decodeBitmapData(currentFrame);
 
-        // copy each source line to the appropriate place in the destination
+        // Copy each source line to the appropriate place in the destination.
         int pass = 1;
         int inc = 8;
         int iline = 0;
@@ -402,14 +397,18 @@ public class GifDecoder {
             line += currentFrame.iy;
             if (line < header.height) {
                 int k = line * header.width;
-                int dx = k + currentFrame.ix; // start of line in dest
-                int dlim = dx + currentFrame.iw; // end of dest line
+                // Start of line in dest.
+                int dx = k + currentFrame.ix;
+                // End of dest line.
+                int dlim = dx + currentFrame.iw;
                 if ((k + header.width) < dlim) {
-                    dlim = k + header.width; // past dest edge
+                    // Past dest edge.
+                    dlim = k + header.width;
                 }
-                int sx = i * currentFrame.iw; // start of line in source
+                // Start of line in source.
+                int sx = i * currentFrame.iw;
                 while (dx < dlim) {
-                    // map color and insert in destination
+                    // Map color and insert in destination.
                     int index = ((int) mainPixels[sx++]) & 0xff;
                     int c = act[index];
                     if (c != 0) {
@@ -420,7 +419,7 @@ public class GifDecoder {
             }
         }
 
-        //Set pixels for current image
+        // Set pixels for current image.
         Bitmap result = getNextBitmap();
         result.setPixels(dest, 0, header.width, 0, 0, header.width, header.height);
         return result;
@@ -429,18 +428,20 @@ public class GifDecoder {
     /**
      * Decodes LZW image data into pixel array. Adapted from John Cristy's BitmapMagick.
      */
-    private void decodeBitmapData(GifFrame frame, byte[] dstPixels) {
+    private void decodeBitmapData(GifFrame frame) {
         if (frame != null) {
-            //Jump to the frame start position
+            // Jump to the frame start position.
             rawData.position(frame.bufferFrameStart);
         }
 
         int nullCode = -1;
         int npix = (frame == null) ? header.width * header.height : frame.iw * frame.ih;
-        int available, clear, code_mask, code_size, end_of_information, in_code, old_code, bits, code, count, i, datum, data_size, first, top, bi, pi;
+        int available, clear, codeMask, codeSize, endOfInformation, inCode, oldCode, bits, code, count, i, datum,
+                dataSize, first, top, bi, pi;
 
-        if (dstPixels == null || dstPixels.length < npix) {
-            dstPixels = new byte[npix]; // allocate new pixel array
+        if (mainPixels == null || mainPixels.length < npix) {
+            // Allocate new pixel array.
+            mainPixels = new byte[npix];
         }
         if (prefix == null) {
             prefix = new short[MAX_STACK_SIZE];
@@ -453,15 +454,16 @@ public class GifDecoder {
         }
 
         // Initialize GIF data stream decoder.
-        data_size = read();
-        clear = 1 << data_size;
-        end_of_information = clear + 1;
+        dataSize = read();
+        clear = 1 << dataSize;
+        endOfInformation = clear + 1;
         available = clear + 2;
-        old_code = nullCode;
-        code_size = data_size + 1;
-        code_mask = (1 << code_size) - 1;
+        oldCode = nullCode;
+        codeSize = dataSize + 1;
+        codeMask = (1 << codeSize) - 1;
         for (code = 0; code < clear; code++) {
-            prefix[code] = 0; // XXX ArrayIndexOutOfBoundsException
+            // XXX ArrayIndexOutOfBoundsException.
+            prefix[code] = 0;
             suffix[code] = (byte) code;
         }
 
@@ -469,7 +471,7 @@ public class GifDecoder {
         datum = bits = count = first = top = pi = bi = 0;
         for (i = 0; i < npix; ) {
             if (top == 0) {
-                if (bits < code_size) {
+                if (bits < codeSize) {
                     // Load bytes until there are enough bits for a code.
                     if (count == 0) {
                         // Read a new data block.
@@ -486,59 +488,60 @@ public class GifDecoder {
                     continue;
                 }
                 // Get the next code.
-                code = datum & code_mask;
-                datum >>= code_size;
-                bits -= code_size;
-                // Interpret the code
-                if ((code > available) || (code == end_of_information)) {
+                code = datum & codeMask;
+                datum >>= codeSize;
+                bits -= codeSize;
+                // Interpret the code.
+                if ((code > available) || (code == endOfInformation)) {
                     break;
                 }
                 if (code == clear) {
                     // Reset decoder.
-                    code_size = data_size + 1;
-                    code_mask = (1 << code_size) - 1;
+                    codeSize = dataSize + 1;
+                    codeMask = (1 << codeSize) - 1;
                     available = clear + 2;
-                    old_code = nullCode;
+                    oldCode = nullCode;
                     continue;
                 }
-                if (old_code == nullCode) {
+                if (oldCode == nullCode) {
                     pixelStack[top++] = suffix[code];
-                    old_code = code;
+                    oldCode = code;
                     first = code;
                     continue;
                 }
-                in_code = code;
+                inCode = code;
                 if (code == available) {
                     pixelStack[top++] = (byte) first;
-                    code = old_code;
+                    code = oldCode;
                 }
                 while (code > clear) {
                     pixelStack[top++] = suffix[code];
                     code = prefix[code];
                 }
                 first = ((int) suffix[code]) & 0xff;
-                // Add a new string to the string table,
+                // Add a new string to the string table.
                 if (available >= MAX_STACK_SIZE) {
                     break;
                 }
                 pixelStack[top++] = (byte) first;
-                prefix[available] = (short) old_code;
+                prefix[available] = (short) oldCode;
                 suffix[available] = (byte) first;
                 available++;
-                if (((available & code_mask) == 0) && (available < MAX_STACK_SIZE)) {
-                    code_size++;
-                    code_mask += available;
+                if (((available & codeMask) == 0) && (available < MAX_STACK_SIZE)) {
+                    codeSize++;
+                    codeMask += available;
                 }
-                old_code = in_code;
+                oldCode = inCode;
             }
             // Pop a pixel off the pixel stack.
             top--;
-            dstPixels[pi++] = pixelStack[top];
+            mainPixels[pi++] = pixelStack[top];
             i++;
         }
 
+        // Clear missing pixels.
         for (i = pi; i < npix; i++) {
-            dstPixels[i] = 0; // clear missing pixels
+            mainPixels[i] = 0;
         }
     }
 
@@ -548,7 +551,7 @@ public class GifDecoder {
     private int read() {
         int curByte = 0;
         try {
-            curByte = (rawData.get() & 0xFF);
+            curByte = rawData.get() & 0xFF;
         } catch (Exception e) {
             header.status = STATUS_FORMAT_ERROR;
         }
@@ -558,7 +561,7 @@ public class GifDecoder {
     /**
      * Reads next variable length block from input.
      *
-     * @return number of bytes stored in "buffer"
+     * @return number of bytes stored in "buffer".
      */
     private int readBlock() {
         int blockSize = read();
diff --git a/third_party/gif_decoder/src/main/java/com/bumptech/glide/gifdecoder/GifFrame.java b/third_party/gif_decoder/src/main/java/com/bumptech/glide/gifdecoder/GifFrame.java
index a315350c..aebe6d64 100644
--- a/third_party/gif_decoder/src/main/java/com/bumptech/glide/gifdecoder/GifFrame.java
+++ b/third_party/gif_decoder/src/main/java/com/bumptech/glide/gifdecoder/GifFrame.java
@@ -1,21 +1,21 @@
 package com.bumptech.glide.gifdecoder;
 
 /**
- * Inner model class housing metadata for each frame
+ * Inner model class housing metadata for each frame.
  */
 class GifFrame {
-    public int ix, iy, iw, ih;
-    /* Control Flags */
-    public boolean interlace;
-    public boolean transparency;
-    /* Disposal Method */
-    public int dispose;
-    /* Transparency Index */
-    public int transIndex;
-    /* Delay, in ms, to next frame */
-    public int delay;
-    /* Index in the raw buffer where we need to start reading to decode */
-    public int bufferFrameStart;
-    /* Local Color Table */
-    public int[] lct;
+    int ix, iy, iw, ih;
+    /* Control Flags. */
+    boolean interlace;
+    boolean transparency;
+    /* Disposal Method. */
+    int dispose;
+    /* Transparency Index. */
+    int transIndex;
+    /* Delay, in ms, to next frame. */
+    int delay;
+    /* Index in the raw buffer where we need to start reading to decode. */
+    int bufferFrameStart;
+    /* Local Color Table. */
+    int[] lct;
 }
diff --git a/third_party/gif_decoder/src/main/java/com/bumptech/glide/gifdecoder/GifHeader.java b/third_party/gif_decoder/src/main/java/com/bumptech/glide/gifdecoder/GifHeader.java
index 4c062088..85604029 100644
--- a/third_party/gif_decoder/src/main/java/com/bumptech/glide/gifdecoder/GifHeader.java
+++ b/third_party/gif_decoder/src/main/java/com/bumptech/glide/gifdecoder/GifHeader.java
@@ -5,27 +5,33 @@ import java.util.List;
 
 public class GifHeader {
 
-    public int[] gct = null;
+    int[] gct = null;
     /**
-     * Global status code of GIF data parsing
+     * Global status code of GIF data parsing.
      */
-    public int status = GifDecoder.STATUS_OK;
-    public int frameCount = 0;
+    int status = GifDecoder.STATUS_OK;
+    int frameCount = 0;
 
-    public GifFrame currentFrame;
-    public List<GifFrame> frames = new ArrayList<GifFrame>();
-     // logical screen size
-    public int width; // full image width
-    public int height; // full image height
+    GifFrame currentFrame;
+    List<GifFrame> frames = new ArrayList<GifFrame>();
+    // Logical screen size.
+    // Full image width.
+    int width;
+    // Full image height.
+    int height;
 
-    public boolean gctFlag; // 1 : global color table flag
-    // 2-4 : color resolution
-    // 5 : gct sort flag
-    public int gctSize; // 6-8 : gct size
-    public int bgIndex; // background color index
-    public int pixelAspect; // pixel aspect ratio
+    // 1 : global color table flag.
+    boolean gctFlag;
+    // 2-4 : color resolution.
+    // 5 : gct sort flag.
+    // 6-8 : gct size.
+    int gctSize;
+    // Background color index.
+    int bgIndex;
+    // Pixel aspect ratio.
+    int pixelAspect;
     //TODO: this is set both during reading the header and while decoding frames...
-    public int bgColor;
-    public boolean isTransparent;
-    public int loopCount;
+    int bgColor;
+    boolean isTransparent;
+    int loopCount;
 }
diff --git a/third_party/gif_decoder/src/main/java/com/bumptech/glide/gifdecoder/GifHeaderParser.java b/third_party/gif_decoder/src/main/java/com/bumptech/glide/gifdecoder/GifHeaderParser.java
index 6237c3cf..af1844d9 100644
--- a/third_party/gif_decoder/src/main/java/com/bumptech/glide/gifdecoder/GifHeaderParser.java
+++ b/third_party/gif_decoder/src/main/java/com/bumptech/glide/gifdecoder/GifHeaderParser.java
@@ -11,18 +11,17 @@ import static com.bumptech.glide.gifdecoder.GifDecoder.STATUS_FORMAT_ERROR;
 public class GifHeaderParser {
     public static final String TAG = "GifHeaderParser";
     /**
-     * max decoder pixel stack size
+     * Max decoder pixel stack size.
      */
     private static final int MAX_STACK_SIZE = 4096;
 
     private final ByteBuffer rawData;
     private GifHeader header = new GifHeader();
 
-    // Raw data read working array
-    protected byte[] block = new byte[256]; // current data block
-    protected int blockSize = 0; // block size last graphic control extension info
-    protected boolean lctFlag; // local color table flag
-    protected int lctSize; // local color table size
+    // Raw data read working array.
+    private byte[] block = new byte[256];
+    // Block size last graphic control extension info.
+    private int blockSize = 0;
     private short[] prefix;
     private byte[] suffix;
     private byte[] pixelStack;
@@ -58,23 +57,27 @@ public class GifHeaderParser {
      * Main file parser. Reads GIF content blocks.
      */
     protected void readContents() {
-        // read GIF file content blocks
+        // Read GIF file content blocks.
         boolean done = false;
         while (!(done || err())) {
             int code = read();
             switch (code) {
-                case 0x2C: // image separator
+                // Image separator.
+                case 0x2C:
                     readBitmap();
                     break;
-                case 0x21: // extension
+                // Extension.
+                case 0x21:
                     code = read();
                     switch (code) {
-                        case 0xf9: // graphics control extension
-                            //Start a new frame
+                        // Graphics control extension.
+                        case 0xf9:
+                            // Start a new frame.
                             header.currentFrame = new GifFrame();
                             readGraphicControlExt();
                             break;
-                        case 0xff: // application extension
+                        // Application extension.
+                        case 0xff:
                             readBlock();
                             String app = "";
                             for (int i = 0; i < 11; i++) {
@@ -83,23 +86,29 @@ public class GifHeaderParser {
                             if (app.equals("NETSCAPE2.0")) {
                                 readNetscapeExt();
                             } else {
-                                skip(); // don't care
+                                // Don't care.
+                                skip();
                             }
                             break;
-                        case 0xfe:// comment extension
+                        // Comment extension.
+                        case 0xfe:
                             skip();
                             break;
-                        case 0x01:// plain text extension
+                        // Plain text extension.
+                        case 0x01:
                             skip();
                             break;
-                        default: // uninteresting extension
+                        // Uninteresting extension.
+                        default:
                             skip();
                     }
                     break;
-                case 0x3b: // terminator
+                // Terminator.
+                case 0x3b:
                     done = true;
                     break;
-                case 0x00: // bad byte, but keep going and see what happens break;
+                // Bad byte, but keep going and see what happens break;
+                case 0x00:
                 default:
                     header.status = STATUS_FORMAT_ERROR;
             }
@@ -107,47 +116,60 @@ public class GifHeaderParser {
     }
 
     /**
-     * Reads Graphics Control Extension values
+     * Reads Graphics Control Extension values.
      */
     protected void readGraphicControlExt() {
-        read(); // block size
-        int packed = read(); // packed fields
-        header.currentFrame.dispose = (packed & 0x1c) >> 2; // disposal method
+        // Block size.
+        read();
+        // Packed fields.
+        int packed = read();
+        // Disposal method.
+        header.currentFrame.dispose = (packed & 0x1c) >> 2;
         if (header.currentFrame.dispose == 0) {
-            header.currentFrame.dispose = 1; // elect to keep old image if discretionary
+            // Elect to keep old image if discretionary.
+            header.currentFrame.dispose = 1;
         }
         header.currentFrame.transparency = (packed & 1) != 0;
         header.isTransparent |= header.currentFrame.transparency;
-        header.currentFrame.delay = readShort() * 10; // delay in milliseconds
-        header.currentFrame.transIndex = read(); // transparent color index
-        read(); // block terminator
+        // Delay in milliseconds.
+        header.currentFrame.delay = readShort() * 10;
+        // Transparent color index
+        header.currentFrame.transIndex = read();
+        // Block terminator
+        read();
     }
 
-     /**
-     * Reads next frame image
+    /**
+     * Reads next frame image.
      */
     protected void readBitmap() {
-        header.currentFrame.ix = readShort(); // (sub)image position & size
+        // (sub)image position & size.
+        header.currentFrame.ix = readShort();
         header.currentFrame.iy = readShort();
         header.currentFrame.iw = readShort();
         header.currentFrame.ih = readShort();
 
         int packed = read();
-        lctFlag = (packed & 0x80) != 0; // 1 - local color table flag interlace
-        lctSize = (int) Math.pow(2, (packed & 0x07) + 1);
+        // 1 - local color table flag interlace
+        boolean lctFlag = (packed & 0x80) != 0;
+        int lctSize = (int) Math.pow(2, (packed & 0x07) + 1);
         // 3 - sort flag
         // 4-5 - reserved lctSize = 2 << (packed & 7); // 6-8 - local color
         // table size
         header.currentFrame.interlace = (packed & 0x40) != 0;
         if (lctFlag) {
-            header.currentFrame.lct = readColorTable(lctSize); // read table
+            // Read table.
+            header.currentFrame.lct = readColorTable(lctSize);
         } else {
-            header.currentFrame.lct = null; //No local color table
+            // No local color table.
+            header.currentFrame.lct = null;
         }
 
-        header.currentFrame.bufferFrameStart = rawData.position(); //Save this as the decoding position pointer
+        // Save this as the decoding position pointer.
+        header.currentFrame.bufferFrameStart = rawData.position();
 
-        skipBitmapData();  // false decode pixel data to advance buffer.
+        // False decode pixel data to advance buffer.
+        skipBitmapData();
 
         skip();
         if (err()) {
@@ -155,16 +177,17 @@ public class GifHeaderParser {
         }
 
         header.frameCount++;
-        header.frames.add(header.currentFrame); // add image to frame
+        // Add image to frame.
+        header.frames.add(header.currentFrame);
     }
-       /**
-     * Reads Netscape extenstion to obtain iteration count
+    /**
+     * Reads Netscape extension to obtain iteration count.
      */
     protected void readNetscapeExt() {
         do {
             readBlock();
             if (block[0] == 1) {
-                // loop count sub-block
+                // Loop count sub-block.
                 int b1 = ((int) block[1]) & 0xff;
                 int b2 = ((int) block[2]) & 0xff;
                 header.loopCount = (b2 << 8) | b1;
@@ -173,7 +196,7 @@ public class GifHeaderParser {
     }
 
 
-       /**
+    /**
      * Reads GIF file header information.
      */
     private void readHeader() {
@@ -191,32 +214,32 @@ public class GifHeaderParser {
             header.bgColor = header.gct[header.bgIndex];
         }
     }
-     /**
-     * Reads Logical Screen Descriptor
+    /**
+     * Reads Logical Screen Descriptor.
      */
     protected void readLSD() {
-        // logical screen size
+        // Logical screen size.
         header.width = readShort();
         header.height = readShort();
-        // packed fields
+        // Packed fields
         int packed = read();
-        header.gctFlag = (packed & 0x80) != 0; // 1 : global color table flag
-        // 2-4 : color resolution
-        // 5 : gct sort flag
-        header.gctSize = 2 << (packed & 7); // 6-8 : gct size
-        header.bgIndex = read(); // background color index
-        header.pixelAspect = read(); // pixel aspect ratio
-
-        //Now that we know the size, init scratch arrays
-        //TODO: these shouldn't go here.
-//        mainPixels = new byte[header.width * header.height];
-//        mainScratch = new int[header.width * header.height];
+        // 1 : global color table flag.
+        header.gctFlag = (packed & 0x80) != 0;
+        // 2-4 : color resolution.
+        // 5 : gct sort flag.
+        // 6-8 : gct size.
+        header.gctSize = 2 << (packed & 7);
+        // Background color index.
+        header.bgIndex = read();
+        // Pixel aspect ratio
+        header.pixelAspect = read();
     }
-     /**
-     * Reads color table as 256 RGB integer values
+
+    /**
+     * Reads color table as 256 RGB integer values.
      *
-     * @param ncolors int number of colors to read
-     * @return int array containing 256 colors (packed ARGB with full alpha)
+     * @param ncolors int number of colors to read.
+     * @return int array containing 256 colors (packed ARGB with full alpha).
      */
     protected int[] readColorTable(int ncolors) {
         int nbytes = 3 * ncolors;
@@ -226,7 +249,8 @@ public class GifHeaderParser {
         try {
             rawData.get(c);
 
-            tab = new int[256]; // max size to avoid bounds checks
+            // Max size to avoid bounds checks.
+            tab = new int[256];
             int i = 0;
             int j = 0;
             while (i < ncolors) {
@@ -243,13 +267,14 @@ public class GifHeaderParser {
         return tab;
     }
 
-      /**
+    /**
      * Decodes LZW image data into pixel array. Adapted from John Cristy's BitmapMagick.
      */
     protected void skipBitmapData() {
         int nullCode = -1;
         int npix = header.width * header.height;
-        int available, clear, code_mask, code_size, end_of_information, in_code, old_code, bits, code, count, i, datum, data_size, first, top, bi, pi;
+        int available, clear, codeMask, codeSize, endOfInformation, inCode, oldCode, bits, code, count, i, datum,
+                dataSize, first, top, bi;
 
         if (prefix == null) {
             prefix = new short[MAX_STACK_SIZE];
@@ -262,27 +287,24 @@ public class GifHeaderParser {
         }
 
         // Initialize GIF data stream decoder.
-        data_size = read();
-        clear = 1 << data_size;
-        end_of_information = clear + 1;
+        dataSize = read();
+        clear = 1 << dataSize;
+        endOfInformation = clear + 1;
         available = clear + 2;
-        old_code = nullCode;
-        code_size = data_size + 1;
-        code_mask = (1 << code_size) - 1;
-        long start = System.currentTimeMillis();
+        oldCode = nullCode;
+        codeSize = dataSize + 1;
+        codeMask = (1 << codeSize) - 1;
         for (code = 0; code < clear; code++) {
-            prefix[code] = 0; // XXX ArrayIndexOutOfBoundsException
+            // XXX ArrayIndexOutOfBoundsException.
+            prefix[code] = 0;
             suffix[code] = (byte) code;
         }
 
-        start = System.currentTimeMillis();
         // Decode GIF pixel stream.
-        datum = bits = count = first = top = pi = bi = 0;
-        int iterations = 0;
+        datum = bits = count = first = top = bi = 0;
         for (i = 0; i < npix; ) {
-            iterations++;
             if (top == 0) {
-                if (bits < code_size) {
+                if (bits < codeSize) {
                     // Load bytes until there are enough bits for a code.
                     if (count == 0) {
                         // Read a new data block.
@@ -299,50 +321,50 @@ public class GifHeaderParser {
                     continue;
                 }
                 // Get the next code.
-                code = datum & code_mask;
-                datum >>= code_size;
-                bits -= code_size;
-                // Interpret the code
-                if ((code > available) || (code == end_of_information)) {
+                code = datum & codeMask;
+                datum >>= codeSize;
+                bits -= codeSize;
+                // Interpret the code.
+                if ((code > available) || (code == endOfInformation)) {
                     break;
                 }
                 if (code == clear) {
                     // Reset decoder.
-                    code_size = data_size + 1;
-                    code_mask = (1 << code_size) - 1;
+                    codeSize = dataSize + 1;
+                    codeMask = (1 << codeSize) - 1;
                     available = clear + 2;
-                    old_code = nullCode;
+                    oldCode = nullCode;
                     continue;
                 }
-                if (old_code == nullCode) {
+                if (oldCode == nullCode) {
                     pixelStack[top++] = suffix[code];
-                    old_code = code;
+                    oldCode = code;
                     first = code;
                     continue;
                 }
-                in_code = code;
+                inCode = code;
                 if (code == available) {
                     pixelStack[top++] = (byte) first;
-                    code = old_code;
+                    code = oldCode;
                 }
                 while (code > clear) {
                     pixelStack[top++] = suffix[code];
                     code = prefix[code];
                 }
                 first = ((int) suffix[code]) & 0xff;
-                // Add a new string to the string table,
+                // Add a new string to the string table.
                 if (available >= MAX_STACK_SIZE) {
                     break;
                 }
                 pixelStack[top++] = (byte) first;
-                prefix[available] = (short) old_code;
+                prefix[available] = (short) oldCode;
                 suffix[available] = (byte) first;
                 available++;
-                if (((available & code_mask) == 0) && (available < MAX_STACK_SIZE)) {
-                    code_size++;
-                    code_mask += available;
+                if (((available & codeMask) == 0) && (available < MAX_STACK_SIZE)) {
+                    codeSize++;
+                    codeMask += available;
                 }
-                old_code = in_code;
+                oldCode = inCode;
             }
             // Pop a pixel off the pixel stack.
             top--;
@@ -350,7 +372,7 @@ public class GifHeaderParser {
         }
     }
 
-      /**
+    /**
      * Skips variable length blocks up to and including next zero length block.
      */
     protected void skip() {
@@ -359,7 +381,7 @@ public class GifHeaderParser {
         } while ((blockSize > 0) && !err());
     }
 
-     /**
+    /**
      * Reads next variable length block from input.
      *
      * @return number of bytes stored in "buffer"
@@ -384,13 +406,13 @@ public class GifHeaderParser {
         return n;
     }
 
-      /**
+    /**
      * Reads a single byte from the input stream.
      */
     private int read() {
         int curByte = 0;
         try {
-            curByte = (rawData.get() & 0xFF);
+            curByte = rawData.get() & 0xFF;
         } catch (Exception e) {
             header.status = STATUS_FORMAT_ERROR;
         }
@@ -398,10 +420,10 @@ public class GifHeaderParser {
     }
 
     /**
-     * Reads next 16-bit value, LSB first
+     * Reads next 16-bit value, LSB first.
      */
     protected int readShort() {
-        // read 16-bit value
+        // Read 16-bit value.
         return rawData.getShort();
     }