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Posted to commits@lucene.apache.org by rm...@apache.org on 2015/04/07 12:59:43 UTC
svn commit: r1671800 -
/lucene/dev/trunk/lucene/core/src/java/org/apache/lucene/util/BitUtil.java
Author: rmuir
Date: Tue Apr 7 10:59:42 2015
New Revision: 1671800
URL: http://svn.apache.org/r1671800
Log:
LUCENE-6374: remove unused BitUtil code
Modified:
lucene/dev/trunk/lucene/core/src/java/org/apache/lucene/util/BitUtil.java
Modified: lucene/dev/trunk/lucene/core/src/java/org/apache/lucene/util/BitUtil.java
URL: http://svn.apache.org/viewvc/lucene/dev/trunk/lucene/core/src/java/org/apache/lucene/util/BitUtil.java?rev=1671800&r1=1671799&r2=1671800&view=diff
==============================================================================
--- lucene/dev/trunk/lucene/core/src/java/org/apache/lucene/util/BitUtil.java (original)
+++ lucene/dev/trunk/lucene/core/src/java/org/apache/lucene/util/BitUtil.java Tue Apr 7 10:59:42 2015
@@ -22,93 +22,8 @@ package org.apache.lucene.util; // from
*/
public final class BitUtil {
- private static final byte[] BYTE_COUNTS = { // table of bits/byte
- 0, 1, 1, 2, 1, 2, 2, 3, 1, 2, 2, 3, 2, 3, 3, 4,
- 1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5,
- 1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5,
- 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,
- 1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5,
- 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,
- 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,
- 3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7,
- 1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5,
- 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,
- 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,
- 3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7,
- 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,
- 3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7,
- 3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7,
- 4, 5, 5, 6, 5, 6, 6, 7, 5, 6, 6, 7, 6, 7, 7, 8
- };
-
- // The General Idea: instead of having an array per byte that has
- // the offsets of the next set bit, that array could be
- // packed inside a 32 bit integer (8 4 bit numbers). That
- // should be faster than accessing an array for each index, and
- // the total array size is kept smaller (256*sizeof(int))=1K
- /* the python code that generated bitlist
- def bits2int(val):
- arr=0
- for shift in range(8,0,-1):
- if val & 0x80:
- arr = (arr << 4) | shift
- val = val << 1
- return arr
-
- def int_table():
- tbl = [ hex(bits2int(val)).strip('L') for val in range(256) ]
- return ','.join(tbl)
- */
- private static final int[] BIT_LISTS = {
- 0x0, 0x1, 0x2, 0x21, 0x3, 0x31, 0x32, 0x321, 0x4, 0x41, 0x42, 0x421, 0x43,
- 0x431, 0x432, 0x4321, 0x5, 0x51, 0x52, 0x521, 0x53, 0x531, 0x532, 0x5321,
- 0x54, 0x541, 0x542, 0x5421, 0x543, 0x5431, 0x5432, 0x54321, 0x6, 0x61, 0x62,
- 0x621, 0x63, 0x631, 0x632, 0x6321, 0x64, 0x641, 0x642, 0x6421, 0x643,
- 0x6431, 0x6432, 0x64321, 0x65, 0x651, 0x652, 0x6521, 0x653, 0x6531, 0x6532,
- 0x65321, 0x654, 0x6541, 0x6542, 0x65421, 0x6543, 0x65431, 0x65432, 0x654321,
- 0x7, 0x71, 0x72, 0x721, 0x73, 0x731, 0x732, 0x7321, 0x74, 0x741, 0x742,
- 0x7421, 0x743, 0x7431, 0x7432, 0x74321, 0x75, 0x751, 0x752, 0x7521, 0x753,
- 0x7531, 0x7532, 0x75321, 0x754, 0x7541, 0x7542, 0x75421, 0x7543, 0x75431,
- 0x75432, 0x754321, 0x76, 0x761, 0x762, 0x7621, 0x763, 0x7631, 0x7632,
- 0x76321, 0x764, 0x7641, 0x7642, 0x76421, 0x7643, 0x76431, 0x76432, 0x764321,
- 0x765, 0x7651, 0x7652, 0x76521, 0x7653, 0x76531, 0x76532, 0x765321, 0x7654,
- 0x76541, 0x76542, 0x765421, 0x76543, 0x765431, 0x765432, 0x7654321, 0x8,
- 0x81, 0x82, 0x821, 0x83, 0x831, 0x832, 0x8321, 0x84, 0x841, 0x842, 0x8421,
- 0x843, 0x8431, 0x8432, 0x84321, 0x85, 0x851, 0x852, 0x8521, 0x853, 0x8531,
- 0x8532, 0x85321, 0x854, 0x8541, 0x8542, 0x85421, 0x8543, 0x85431, 0x85432,
- 0x854321, 0x86, 0x861, 0x862, 0x8621, 0x863, 0x8631, 0x8632, 0x86321, 0x864,
- 0x8641, 0x8642, 0x86421, 0x8643, 0x86431, 0x86432, 0x864321, 0x865, 0x8651,
- 0x8652, 0x86521, 0x8653, 0x86531, 0x86532, 0x865321, 0x8654, 0x86541,
- 0x86542, 0x865421, 0x86543, 0x865431, 0x865432, 0x8654321, 0x87, 0x871,
- 0x872, 0x8721, 0x873, 0x8731, 0x8732, 0x87321, 0x874, 0x8741, 0x8742,
- 0x87421, 0x8743, 0x87431, 0x87432, 0x874321, 0x875, 0x8751, 0x8752, 0x87521,
- 0x8753, 0x87531, 0x87532, 0x875321, 0x8754, 0x87541, 0x87542, 0x875421,
- 0x87543, 0x875431, 0x875432, 0x8754321, 0x876, 0x8761, 0x8762, 0x87621,
- 0x8763, 0x87631, 0x87632, 0x876321, 0x8764, 0x87641, 0x87642, 0x876421,
- 0x87643, 0x876431, 0x876432, 0x8764321, 0x8765, 0x87651, 0x87652, 0x876521,
- 0x87653, 0x876531, 0x876532, 0x8765321, 0x87654, 0x876541, 0x876542,
- 0x8765421, 0x876543, 0x8765431, 0x8765432, 0x87654321
- };
-
private BitUtil() {} // no instance
- /** Return the number of bits sets in b. */
- public static int bitCount(byte b) {
- return BYTE_COUNTS[b & 0xFF];
- }
-
- /** Return the list of bits which are set in b encoded as followed:
- * {@code (i >>> (4 * n)) & 0x0F} is the offset of the n-th set bit of
- * the given byte plus one, or 0 if there are n or less bits set in the given
- * byte. For example <code>bitList(12)</code> returns 0x43:<ul>
- * <li>{@code 0x43 & 0x0F} is 3, meaning the the first bit set is at offset 3-1 = 2,</li>
- * <li>{@code (0x43 >>> 4) & 0x0F} is 4, meaning there is a second bit set at offset 4-1=3,</li>
- * <li>{@code (0x43 >>> 8) & 0x0F} is 0, meaning there is no more bit set in this byte.</li>
- * </ul>*/
- public static int bitList(byte b) {
- return BIT_LISTS[b & 0xFF];
- }
-
// The pop methods used to rely on bit-manipulation tricks for speed but it
// turns out that it is faster to use the Long.bitCount method (which is an
// intrinsic since Java 6u18) in a naive loop, see LUCENE-2221