Code analysis tweaks

git-svn-id: https://zxing.googlecode.com/svn/trunk@1003 59b500cc-1b3d-0410-9834-0bbf25fbcc57

core/src/com/google/zxing/Binarizer.java

@@ -31,7 +31,7 @@ public abstract class Binarizer {
 
   private final LuminanceSource source;
 
-  public Binarizer(LuminanceSource source) {
+  protected Binarizer(LuminanceSource source) {
     if (source == null) {
       throw new IllegalArgumentException("Source must be non-null.");
     }

core/src/com/google/zxing/LuminanceSource.java

@@ -30,7 +30,7 @@ public abstract class LuminanceSource {
   private final int width;
   private final int height;
 
-  public LuminanceSource(int width, int height) {
+  protected LuminanceSource(int width, int height) {
     this.width = width;
     this.height = height;
   }

core/src/com/google/zxing/common/ByteArray.java

@@ -60,7 +60,7 @@ public final class ByteArray {
     return size;
   }
 
-  public boolean empty() {
+  public boolean isEmpty() {
     return size == 0;
   }
 

core/src/com/google/zxing/common/ByteMatrix.java

@@ -70,7 +70,7 @@ public final class ByteMatrix {
   }
 
   public String toString() {
-    StringBuffer result = new StringBuffer();
+    StringBuffer result = new StringBuffer(2 * width * height + 2);
     for (int y = 0; y < height; ++y) {
       for (int x = 0; x < width; ++x) {
         switch (bytes[y][x]) {

core/src/com/google/zxing/common/GlobalHistogramBinarizer.java

@@ -90,7 +90,7 @@ public final class GlobalHistogramBinarizer extends Binarizer {
     for (int y = 1; y < 5; y++) {
       int row = height * y / 5;
       byte[] localLuminances = source.getRow(row, luminances);
-      int right = width * 4 / 5;
+      int right = (width << 2) / 5;
       for (int x = width / 5; x < right; x++) {
         int pixel = localLuminances[x] & 0xff;
         localBuckets[pixel >> LUMINANCE_SHIFT]++;

core/src/com/google/zxing/common/LocalBlockBinarizer.java

@@ -17,7 +17,6 @@
 package com.google.zxing.common;
 
 import com.google.zxing.Binarizer;
-import com.google.zxing.ReaderException;
 import com.google.zxing.LuminanceSource;
 
 /**
@@ -38,12 +37,12 @@ public final class LocalBlockBinarizer extends Binarizer {
     super(source);
   }
 
-  public BitArray getBlackRow(int y, BitArray row) throws ReaderException {
+  public BitArray getBlackRow(int y, BitArray row) {
     binarizeEntireImage();
     return matrix.getRow(y, row);
   }
 
-  public BitMatrix getBlackMatrix() throws ReaderException {
+  public BitMatrix getBlackMatrix() {
     binarizeEntireImage();
     return matrix;
   }
@@ -80,11 +79,11 @@ public final class LocalBlockBinarizer extends Binarizer {
       int stride, int[][] blackPoints, BitMatrix matrix) {
     for (int y = 0; y < subHeight; y++) {
       for (int x = 0; x < subWidth; x++) {
-        int sum = 0;
         int left = (x > 1) ? x : 2;
         left = (left < subWidth - 2) ? left : subWidth - 3;
         int top = (y > 1) ? y : 2;
         top = (top < subHeight - 2) ? top : subHeight - 3;
+        int sum = 0;
         for (int z = -2; z <= 2; z++) {
           sum += blackPoints[top + z][left - 2];
           sum += blackPoints[top + z][left - 1];
@@ -93,7 +92,7 @@ public final class LocalBlockBinarizer extends Binarizer {
           sum += blackPoints[top + z][left + 2];
         }
         int average = sum / 25;
-        threshold8x8Block(luminances, x * 8, y * 8, average, stride, matrix);
+        threshold8x8Block(luminances, x << 3, y << 3, average, stride, matrix);
       }
     }
   }
@@ -122,7 +121,7 @@ public final class LocalBlockBinarizer extends Binarizer {
         int min = 255;
         int max = 0;
         for (int yy = 0; yy < 8; yy++) {
-          int offset = (y * 8 + yy) * stride + (x * 8);
+          int offset = ((y << 3) + yy) * stride + (x << 3);
           for (int xx = 0; xx < 8; xx++) {
             int pixel = luminances[offset + xx] & 0xff;
             sum += pixel;

core/src/com/google/zxing/common/detector/MonochromeRectangleDetector.java

@@ -18,7 +18,6 @@ package com.google.zxing.common.detector;
 
 import com.google.zxing.ReaderException;
 import com.google.zxing.ResultPoint;
-import com.google.zxing.common.BitArray;
 import com.google.zxing.common.BitMatrix;
 
 /**