1 files changed, 246 insertions, 0 deletions
diff --git a/libraries/zxing/src/com/google/zxing/common/BitArray.java b/libraries/zxing/src/com/google/zxing/common/BitArray.java
new file mode 100644
index 000000000..6eb0d57c6
--- /dev/null
+++ b/libraries/zxing/src/com/google/zxing/common/BitArray.java
@@ -0,0 +1,246 @@
+/*
+ * Copyright 2007 ZXing authors
+ *
+ * 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.google.zxing.common;
+
+/**
+ * <p>A simple, fast array of bits, represented compactly by an array of ints internally.</p>
+ *
+ * @author Sean Owen
+ */
+public final class BitArray {
+  // I have changed these members to be public so ProGuard can inline get() and set(). Ideally
+  // they'd be private and we'd use the -allowaccessmodification flag, but Dalvik rejects the
+  // resulting binary at runtime on Android. If we find a solution to this, these should be changed
+  // back to private.
+  public int[] bits;
+  public int size;
+
+  public BitArray() {
+    this.size = 0;
+    this.bits = new int[1];
+  }
+
+  public BitArray(int size) {
+    this.size = size;
+    this.bits = makeArray(size);
+  }
+
+  public int getSize() {
+    return size;
+  }
+
+  public int getSizeInBytes() {
+    return (size + 7) >> 3;
+  }
+
+  private void ensureCapacity(int size) {
+    if (size > bits.length << 5) {
+      int[] newBits = makeArray(size);
+      System.arraycopy(bits, 0, newBits, 0, bits.length);
+      this.bits = newBits;
+    }
+  }
+
+  /**
+   * @param i bit to get
+   * @return true iff bit i is set
+   */
+  public boolean get(int i) {
+    return (bits[i >> 5] & (1 << (i & 0x1F))) != 0;
+  }
+
+  /**
+   * Sets bit i.
+   *
+   * @param i bit to set
+   */
+  public void set(int i) {
+    bits[i >> 5] |= 1 << (i & 0x1F);
+  }
+
+  /**
+   * Flips bit i.
+   *
+   * @param i bit to set
+   */
+  public void flip(int i) {
+    bits[i >> 5] ^= 1 << (i & 0x1F);
+  }
+
+  /**
+   * Sets a block of 32 bits, starting at bit i.
+   *
+   * @param i first bit to set
+   * @param newBits the new value of the next 32 bits. Note again that the least-significant bit
+   * corresponds to bit i, the next-least-significant to i+1, and so on.
+   */
+  public void setBulk(int i, int newBits) {
+    bits[i >> 5] = newBits;
+  }
+
+  /**
+   * Clears all bits (sets to false).
+   */
+  public void clear() {
+    int max = bits.length;
+    for (int i = 0; i < max; i++) {
+      bits[i] = 0;
+    }
+  }
+
+  /**
+   * Efficient method to check if a range of bits is set, or not set.
+   *
+   * @param start start of range, inclusive.
+   * @param end end of range, exclusive
+   * @param value if true, checks that bits in range are set, otherwise checks that they are not set
+   * @return true iff all bits are set or not set in range, according to value argument
+   * @throws IllegalArgumentException if end is less than or equal to start
+   */
+  public boolean isRange(int start, int end, boolean value) {
+    if (end < start) {
+      throw new IllegalArgumentException();
+    }
+    if (end == start) {
+      return true; // empty range matches
+    }
+    end--; // will be easier to treat this as the last actually set bit -- inclusive
+    int firstInt = start >> 5;
+    int lastInt = end >> 5;
+    for (int i = firstInt; i <= lastInt; i++) {
+      int firstBit = i > firstInt ? 0 : start & 0x1F;
+      int lastBit = i < lastInt ? 31 : end & 0x1F;
+      int mask;
+      if (firstBit == 0 && lastBit == 31) {
+        mask = -1;
+      } else {
+        mask = 0;
+        for (int j = firstBit; j <= lastBit; j++) {
+          mask |= 1 << j;
+        }
+      }
+
+      // Return false if we're looking for 1s and the masked bits[i] isn't all 1s (that is,
+      // equals the mask, or we're looking for 0s and the masked portion is not all 0s
+      if ((bits[i] & mask) != (value ? mask : 0)) {
+        return false;
+      }
+    }
+    return true;
+  }
+
+  public void appendBit(boolean bit) {
+    ensureCapacity(size + 1);
+    if (bit) {
+      bits[size >> 5] |= (1 << (size & 0x1F));
+    }
+    size++;
+  }
+
+  /**
+   * Appends the least-significant bits, from value, in order from most-significant to
+   * least-significant. For example, appending 6 bits from 0x000001E will append the bits
+   * 0, 1, 1, 1, 1, 0 in that order.
+   */
+  public void appendBits(int value, int numBits) {
+    if (numBits < 0 || numBits > 32) {
+      throw new IllegalArgumentException("Num bits must be between 0 and 32");
+    }
+    ensureCapacity(size + numBits);
+    for (int numBitsLeft = numBits; numBitsLeft > 0; numBitsLeft--) {
+      appendBit(((value >> (numBitsLeft - 1)) & 0x01) == 1);
+    }
+  }
+
+  public void appendBitArray(BitArray other) {
+    int otherSize = other.getSize();
+    ensureCapacity(size + otherSize);
+    for (int i = 0; i < otherSize; i++) {
+      appendBit(other.get(i));
+    }
+  }
+
+  public void xor(BitArray other) {
+    if (bits.length != other.bits.length) {
+      throw new IllegalArgumentException("Sizes don't match");
+    }
+    for (int i = 0; i < bits.length; i++) {
+      // The last byte could be incomplete (i.e. not have 8 bits in
+      // it) but there is no problem since 0 XOR 0 == 0.
+      bits[i] ^= other.bits[i];
+    }
+  }
+
+  /**
+   *
+   * @param bitOffset first bit to start writing
+   * @param array array to write into. Bytes are written most-significant byte first. This is the opposite
+   *  of the internal representation, which is exposed by {@link #getBitArray()}
+   * @param offset position in array to start writing
+   * @param numBytes how many bytes to write
+   */
+  public void toBytes(int bitOffset, byte[] array, int offset, int numBytes) {
+    for (int i = 0; i < numBytes; i++) {
+      int theByte = 0;
+      for (int j = 0; j < 8; j++) {
+        if (get(bitOffset)) {
+          theByte |= 1 << (7 - j);
+        }
+        bitOffset++;
+      }
+      array[offset + i] = (byte) theByte;
+    }
+  }
+
+  /**
+   * @return underlying array of ints. The first element holds the first 32 bits, and the least
+   *         significant bit is bit 0.
+   */
+  public int[] getBitArray() {
+    return bits;
+  }
+
+  /**
+   * Reverses all bits in the array.
+   */
+  public void reverse() {
+    int[] newBits = new int[bits.length];
+    int size = this.size;
+    for (int i = 0; i < size; i++) {
+      if (get(size - i - 1)) {
+        newBits[i >> 5] |= 1 << (i & 0x1F);
+      }
+    }
+    bits = newBits;
+  }
+
+  private static int[] makeArray(int size) {
+    return new int[(size + 31) >> 5];
+  }
+
+  public String toString() {
+    StringBuffer result = new StringBuffer(size);
+    for (int i = 0; i < size; i++) {
+      if ((i & 0x07) == 0) {
+        result.append(' ');
+      }
+      result.append(get(i) ? 'X' : '.');
+    }
+    return result.toString();
+  }
+
+}
+\ No newline at end of file