Code tweaks and so forth with Daniel

[zxing.git] / core / src / com / google / zxing / common / BitArray.java

diff --git a/core/src/com/google/zxing/common/BitArray.java b/core/src/com/google/zxing/common/BitArray.java
index 398be9e..67cdbfd 100644 (file)
--- a/core/src/com/google/zxing/common/BitArray.java
+++ b/core/src/com/google/zxing/common/BitArray.java
@@ -23,17 +23,16 @@ package com.google.zxing.common;
  */\r
 public final class BitArray {\r
 \r
-  private final int[] bits;\r
+  private int[] bits;\r
+  private int size;\r
 \r
   public BitArray(int size) {\r
-    int arraySize = size >> 5;\r
-    if ((size & 0x1F) != 0) {\r
-      arraySize++;\r
-    }\r
-    bits = new int[arraySize];\r
+    this.size = size;\r
+    this.bits = makeArray(size);\r
   }\r
 \r
   /**\r
+   * @param i bit to get\r
    * @return true iff bit i is set\r
    */\r
   public boolean get(int i) {\r
@@ -42,17 +41,26 @@ public final class BitArray {
 \r
   /**\r
    * Sets bit i.\r
+   *\r
+   * @param i bit to set\r
    */\r
   public void set(int i) {\r
     bits[i >> 5] |= 1 << (i & 0x1F);\r
   }\r
 \r
+  /**\r
+   * Sets a block of 32 bits, starting at bit i.\r
+   *\r
+   * @param i first bit to set\r
+   * @param newBits the new value of the next 32 bits. Note again that the least-significant bit\r
+   *  corresponds to bit i, the next-least-significant to i+1, and so on.\r
+   */\r
   public void setBulk(int i, int newBits) {\r
     bits[i >> 5] = newBits;\r
   }\r
 \r
   /**\r
-   * Clears all bits.\r
+   * Clears all bits (sets to false).\r
    */\r
   public void clear() {\r
     int max = bits.length;\r
@@ -68,5 +76,31 @@ public final class BitArray {
   public int[] getBitArray() {\r
     return bits;\r
   }\r
+  \r
+  /**\r
+   * Reverses all bits in the array.\r
+   */\r
+  public void reverse() {\r
+    int[] newBits = makeArray(size);\r
+    int max = newBits.length;\r
+    for (int i = 0; i < max; i++) {\r
+      newBits[i] = 0;\r
+    }\r
+    int size = this.size;\r
+    for (int i = 0; i < size; i++) {\r
+      if (get(size - i - 1)) {\r
+        newBits[i >> 5] |= 1 << (i & 0x1F);\r
+      }\r
+    }\r
+    bits = newBits;\r
+  }\r
+  \r
+  private static int[] makeArray(int size) {\r
+    int arraySize = size >> 5;\r
+    if ((size & 0x1F) != 0) {\r
+      arraySize++;\r
+    }\r
+    return new int[arraySize];\r
+  }\r
 \r
 }
\ No newline at end of file