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-rw-r--r--libraries/zxing/src/com/google/zxing/common/BitSource.java97
1 files changed, 0 insertions, 97 deletions
diff --git a/libraries/zxing/src/com/google/zxing/common/BitSource.java b/libraries/zxing/src/com/google/zxing/common/BitSource.java
deleted file mode 100644
index a61ac5105..000000000
--- a/libraries/zxing/src/com/google/zxing/common/BitSource.java
+++ /dev/null
@@ -1,97 +0,0 @@
-/*
- * 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>This provides an easy abstraction to read bits at a time from a sequence of bytes, where the
- * number of bits read is not often a multiple of 8.</p>
- *
- * <p>This class is thread-safe but not reentrant. Unless the caller modifies the bytes array
- * it passed in, in which case all bets are off.</p>
- *
- * @author Sean Owen
- */
-public final class BitSource {
-
- private final byte[] bytes;
- private int byteOffset;
- private int bitOffset;
-
- /**
- * @param bytes bytes from which this will read bits. Bits will be read from the first byte first.
- * Bits are read within a byte from most-significant to least-significant bit.
- */
- public BitSource(byte[] bytes) {
- this.bytes = bytes;
- }
-
- /**
- * @param numBits number of bits to read
- * @return int representing the bits read. The bits will appear as the least-significant
- * bits of the int
- * @throws IllegalArgumentException if numBits isn't in [1,32]
- */
- public int readBits(int numBits) {
- if (numBits < 1 || numBits > 32) {
- throw new IllegalArgumentException();
- }
-
- int result = 0;
-
- // First, read remainder from current byte
- if (bitOffset > 0) {
- int bitsLeft = 8 - bitOffset;
- int toRead = numBits < bitsLeft ? numBits : bitsLeft;
- int bitsToNotRead = bitsLeft - toRead;
- int mask = (0xFF >> (8 - toRead)) << bitsToNotRead;
- result = (bytes[byteOffset] & mask) >> bitsToNotRead;
- numBits -= toRead;
- bitOffset += toRead;
- if (bitOffset == 8) {
- bitOffset = 0;
- byteOffset++;
- }
- }
-
- // Next read whole bytes
- if (numBits > 0) {
- while (numBits >= 8) {
- result = (result << 8) | (bytes[byteOffset] & 0xFF);
- byteOffset++;
- numBits -= 8;
- }
-
- // Finally read a partial byte
- if (numBits > 0) {
- int bitsToNotRead = 8 - numBits;
- int mask = (0xFF >> bitsToNotRead) << bitsToNotRead;
- result = (result << numBits) | ((bytes[byteOffset] & mask) >> bitsToNotRead);
- bitOffset += numBits;
- }
- }
-
- return result;
- }
-
- /**
- * @return number of bits that can be read successfully
- */
- public int available() {
- return 8 * (bytes.length - byteOffset) - bitOffset;
- }
-
-}