coderplay
3/29/2013 - 4:20 AM
group variant integer encoding
group variant integer encoding
import java.lang.reflect.Field;
import java.util.Random;
import sun.misc.Unsafe;
public class GroupVarInt {
private final static int UINT24_MAX = ((2<<23) - 1);
private final static int UINT16_MAX = ((2<<15) - 1);
private final static int UINT8_MAX = ((2<<7) -1);
private static final long BYTE_ARRAY_OFFSET;
public static final Unsafe unsafe;
static {
try {
Field field = Unsafe.class.getDeclaredField("theUnsafe");
field.setAccessible(true);
unsafe = (Unsafe) field.get(null);
BYTE_ARRAY_OFFSET = unsafe.arrayBaseOffset(byte[].class);
} catch (Exception e) {
throw new RuntimeException(e);
}
}
private final static byte GROUP_VARINT_IDX_ARR[][] = {
/* 00 00 00 00 */{2, 3, 4, 1, 1, 1, 1, 5},
/* 00 00 00 01 */{2, 3, 4, 1, 1, 1, 2, 6},
/* 00 00 00 10 */{2, 3, 4, 1, 1, 1, 3, 7},
/* 00 00 00 11 */{2, 3, 4, 1, 1, 1, 4, 8},
/* 00 00 01 00 */{2, 3, 5, 1, 1, 2, 1, 6},
/* 00 00 01 01 */{2, 3, 5, 1, 1, 2, 2, 7},
/* 00 00 01 10 */{2, 3, 5, 1, 1, 2, 3, 8},
/* 00 00 01 11 */{2, 3, 5, 1, 1, 2, 4, 9},
/* 00 00 10 00 */{2, 3, 6, 1, 1, 3, 1, 7},
/* 00 00 10 01 */{2, 3, 6, 1, 1, 3, 2, 8},
/* 00 00 10 10 */{2, 3, 6, 1, 1, 3, 3, 9},
/* 00 00 10 11 */{2, 3, 6, 1, 1, 3, 4, 10},
/* 00 00 11 00 */{2, 3, 7, 1, 1, 4, 1, 8},
/* 00 00 11 01 */{2, 3, 7, 1, 1, 4, 2, 9},
/* 00 00 11 10 */{2, 3, 7, 1, 1, 4, 3, 10},
/* 00 00 11 11 */{2, 3, 7, 1, 1, 4, 4, 11},
/* 00 01 00 00 */{2, 4, 5, 1, 2, 1, 1, 6},
/* 00 01 00 01 */{2, 4, 5, 1, 2, 1, 2, 7},
/* 00 01 00 10 */{2, 4, 5, 1, 2, 1, 3, 8},
/* 00 01 00 11 */{2, 4, 5, 1, 2, 1, 4, 9},
/* 00 01 01 00 */{2, 4, 6, 1, 2, 2, 1, 7},
/* 00 01 01 01 */{2, 4, 6, 1, 2, 2, 2, 8},
/* 00 01 01 10 */{2, 4, 6, 1, 2, 2, 3, 9},
/* 00 01 01 11 */{2, 4, 6, 1, 2, 2, 4, 10},
/* 00 01 10 00 */{2, 4, 7, 1, 2, 3, 1, 8},
/* 00 01 10 01 */{2, 4, 7, 1, 2, 3, 2, 9},
/* 00 01 10 10 */{2, 4, 7, 1, 2, 3, 3, 10},
/* 00 01 10 11 */{2, 4, 7, 1, 2, 3, 4, 11},
/* 00 01 11 00 */{2, 4, 8, 1, 2, 4, 1, 9},
/* 00 01 11 01 */{2, 4, 8, 1, 2, 4, 2, 10},
/* 00 01 11 10 */{2, 4, 8, 1, 2, 4, 3, 11},
/* 00 01 11 11 */{2, 4, 8, 1, 2, 4, 4, 12},
/* 00 10 00 00 */{2, 5, 6, 1, 3, 1, 1, 7},
/* 00 10 00 01 */{2, 5, 6, 1, 3, 1, 2, 8},
/* 00 10 00 10 */{2, 5, 6, 1, 3, 1, 3, 9},
/* 00 10 00 11 */{2, 5, 6, 1, 3, 1, 4, 10},
/* 00 10 01 00 */{2, 5, 7, 1, 3, 2, 1, 8},
/* 00 10 01 01 */{2, 5, 7, 1, 3, 2, 2, 9},
/* 00 10 01 10 */{2, 5, 7, 1, 3, 2, 3, 10},
/* 00 10 01 11 */{2, 5, 7, 1, 3, 2, 4, 11},
/* 00 10 10 00 */{2, 5, 8, 1, 3, 3, 1, 9},
/* 00 10 10 01 */{2, 5, 8, 1, 3, 3, 2, 10},
/* 00 10 10 10 */{2, 5, 8, 1, 3, 3, 3, 11},
/* 00 10 10 11 */{2, 5, 8, 1, 3, 3, 4, 12},
/* 00 10 11 00 */{2, 5, 9, 1, 3, 4, 1, 10},
/* 00 10 11 01 */{2, 5, 9, 1, 3, 4, 2, 11},
/* 00 10 11 10 */{2, 5, 9, 1, 3, 4, 3, 12},
/* 00 10 11 11 */{2, 5, 9, 1, 3, 4, 4, 13},
/* 00 11 00 00 */{2, 6, 7, 1, 4, 1, 1, 8},
/* 00 11 00 01 */{2, 6, 7, 1, 4, 1, 2, 9},
/* 00 11 00 10 */{2, 6, 7, 1, 4, 1, 3, 10},
/* 00 11 00 11 */{2, 6, 7, 1, 4, 1, 4, 11},
/* 00 11 01 00 */{2, 6, 8, 1, 4, 2, 1, 9},
/* 00 11 01 01 */{2, 6, 8, 1, 4, 2, 2, 10},
/* 00 11 01 10 */{2, 6, 8, 1, 4, 2, 3, 11},
/* 00 11 01 11 */{2, 6, 8, 1, 4, 2, 4, 12},
/* 00 11 10 00 */{2, 6, 9, 1, 4, 3, 1, 10},
/* 00 11 10 01 */{2, 6, 9, 1, 4, 3, 2, 11},
/* 00 11 10 10 */{2, 6, 9, 1, 4, 3, 3, 12},
/* 00 11 10 11 */{2, 6, 9, 1, 4, 3, 4, 13},
/* 00 11 11 00 */{2, 6, 10, 1, 4, 4, 1, 11},
/* 00 11 11 01 */{2, 6, 10, 1, 4, 4, 2, 12},
/* 00 11 11 10 */{2, 6, 10, 1, 4, 4, 3, 13},
/* 00 11 11 11 */{2, 6, 10, 1, 4, 4, 4, 14},
/* 01 00 00 00 */{3, 4, 5, 2, 1, 1, 1, 6},
/* 01 00 00 01 */{3, 4, 5, 2, 1, 1, 2, 7},
/* 01 00 00 10 */{3, 4, 5, 2, 1, 1, 3, 8},
/* 01 00 00 11 */{3, 4, 5, 2, 1, 1, 4, 9},
/* 01 00 01 00 */{3, 4, 6, 2, 1, 2, 1, 7},
/* 01 00 01 01 */{3, 4, 6, 2, 1, 2, 2, 8},
/* 01 00 01 10 */{3, 4, 6, 2, 1, 2, 3, 9},
/* 01 00 01 11 */{3, 4, 6, 2, 1, 2, 4, 10},
/* 01 00 10 00 */{3, 4, 7, 2, 1, 3, 1, 8},
/* 01 00 10 01 */{3, 4, 7, 2, 1, 3, 2, 9},
/* 01 00 10 10 */{3, 4, 7, 2, 1, 3, 3, 10},
/* 01 00 10 11 */{3, 4, 7, 2, 1, 3, 4, 11},
/* 01 00 11 00 */{3, 4, 8, 2, 1, 4, 1, 9},
/* 01 00 11 01 */{3, 4, 8, 2, 1, 4, 2, 10},
/* 01 00 11 10 */{3, 4, 8, 2, 1, 4, 3, 11},
/* 01 00 11 11 */{3, 4, 8, 2, 1, 4, 4, 12},
/* 01 01 00 00 */{3, 5, 6, 2, 2, 1, 1, 7},
/* 01 01 00 01 */{3, 5, 6, 2, 2, 1, 2, 8},
/* 01 01 00 10 */{3, 5, 6, 2, 2, 1, 3, 9},
/* 01 01 00 11 */{3, 5, 6, 2, 2, 1, 4, 10},
/* 01 01 01 00 */{3, 5, 7, 2, 2, 2, 1, 8},
/* 01 01 01 01 */{3, 5, 7, 2, 2, 2, 2, 9},
/* 01 01 01 10 */{3, 5, 7, 2, 2, 2, 3, 10},
/* 01 01 01 11 */{3, 5, 7, 2, 2, 2, 4, 11},
/* 01 01 10 00 */{3, 5, 8, 2, 2, 3, 1, 9},
/* 01 01 10 01 */{3, 5, 8, 2, 2, 3, 2, 10},
/* 01 01 10 10 */{3, 5, 8, 2, 2, 3, 3, 11},
/* 01 01 10 11 */{3, 5, 8, 2, 2, 3, 4, 12},
/* 01 01 11 00 */{3, 5, 9, 2, 2, 4, 1, 10},
/* 01 01 11 01 */{3, 5, 9, 2, 2, 4, 2, 11},
/* 01 01 11 10 */{3, 5, 9, 2, 2, 4, 3, 12},
/* 01 01 11 11 */{3, 5, 9, 2, 2, 4, 4, 13},
/* 01 10 00 00 */{3, 6, 7, 2, 3, 1, 1, 8},
/* 01 10 00 01 */{3, 6, 7, 2, 3, 1, 2, 9},
/* 01 10 00 10 */{3, 6, 7, 2, 3, 1, 3, 10},
/* 01 10 00 11 */{3, 6, 7, 2, 3, 1, 4, 11},
/* 01 10 01 00 */{3, 6, 8, 2, 3, 2, 1, 9},
/* 01 10 01 01 */{3, 6, 8, 2, 3, 2, 2, 10},
/* 01 10 01 10 */{3, 6, 8, 2, 3, 2, 3, 11},
/* 01 10 01 11 */{3, 6, 8, 2, 3, 2, 4, 12},
/* 01 10 10 00 */{3, 6, 9, 2, 3, 3, 1, 10},
/* 01 10 10 01 */{3, 6, 9, 2, 3, 3, 2, 11},
/* 01 10 10 10 */{3, 6, 9, 2, 3, 3, 3, 12},
/* 01 10 10 11 */{3, 6, 9, 2, 3, 3, 4, 13},
/* 01 10 11 00 */{3, 6, 10, 2, 3, 4, 1, 11},
/* 01 10 11 01 */{3, 6, 10, 2, 3, 4, 2, 12},
/* 01 10 11 10 */{3, 6, 10, 2, 3, 4, 3, 13},
/* 01 10 11 11 */{3, 6, 10, 2, 3, 4, 4, 14},
/* 01 11 00 00 */{3, 7, 8, 2, 4, 1, 1, 9},
/* 01 11 00 01 */{3, 7, 8, 2, 4, 1, 2, 10},
/* 01 11 00 10 */{3, 7, 8, 2, 4, 1, 3, 11},
/* 01 11 00 11 */{3, 7, 8, 2, 4, 1, 4, 12},
/* 01 11 01 00 */{3, 7, 9, 2, 4, 2, 1, 10},
/* 01 11 01 01 */{3, 7, 9, 2, 4, 2, 2, 11},
/* 01 11 01 10 */{3, 7, 9, 2, 4, 2, 3, 12},
/* 01 11 01 11 */{3, 7, 9, 2, 4, 2, 4, 13},
/* 01 11 10 00 */{3, 7, 10, 2, 4, 3, 1, 11},
/* 01 11 10 01 */{3, 7, 10, 2, 4, 3, 2, 12},
/* 01 11 10 10 */{3, 7, 10, 2, 4, 3, 3, 13},
/* 01 11 10 11 */{3, 7, 10, 2, 4, 3, 4, 14},
/* 01 11 11 00 */{3, 7, 11, 2, 4, 4, 1, 12},
/* 01 11 11 01 */{3, 7, 11, 2, 4, 4, 2, 13},
/* 01 11 11 10 */{3, 7, 11, 2, 4, 4, 3, 14},
/* 01 11 11 11 */{3, 7, 11, 2, 4, 4, 4, 15},
/* 10 00 00 00 */{4, 5, 6, 3, 1, 1, 1, 7},
/* 10 00 00 01 */{4, 5, 6, 3, 1, 1, 2, 8},
/* 10 00 00 10 */{4, 5, 6, 3, 1, 1, 3, 9},
/* 10 00 00 11 */{4, 5, 6, 3, 1, 1, 4, 10},
/* 10 00 01 00 */{4, 5, 7, 3, 1, 2, 1, 8},
/* 10 00 01 01 */{4, 5, 7, 3, 1, 2, 2, 9},
/* 10 00 01 10 */{4, 5, 7, 3, 1, 2, 3, 10},
/* 10 00 01 11 */{4, 5, 7, 3, 1, 2, 4, 11},
/* 10 00 10 00 */{4, 5, 8, 3, 1, 3, 1, 9},
/* 10 00 10 01 */{4, 5, 8, 3, 1, 3, 2, 10},
/* 10 00 10 10 */{4, 5, 8, 3, 1, 3, 3, 11},
/* 10 00 10 11 */{4, 5, 8, 3, 1, 3, 4, 12},
/* 10 00 11 00 */{4, 5, 9, 3, 1, 4, 1, 10},
/* 10 00 11 01 */{4, 5, 9, 3, 1, 4, 2, 11},
/* 10 00 11 10 */{4, 5, 9, 3, 1, 4, 3, 12},
/* 10 00 11 11 */{4, 5, 9, 3, 1, 4, 4, 13},
/* 10 01 00 00 */{4, 6, 7, 3, 2, 1, 1, 8},
/* 10 01 00 01 */{4, 6, 7, 3, 2, 1, 2, 9},
/* 10 01 00 10 */{4, 6, 7, 3, 2, 1, 3, 10},
/* 10 01 00 11 */{4, 6, 7, 3, 2, 1, 4, 11},
/* 10 01 01 00 */{4, 6, 8, 3, 2, 2, 1, 9},
/* 10 01 01 01 */{4, 6, 8, 3, 2, 2, 2, 10},
/* 10 01 01 10 */{4, 6, 8, 3, 2, 2, 3, 11},
/* 10 01 01 11 */{4, 6, 8, 3, 2, 2, 4, 12},
/* 10 01 10 00 */{4, 6, 9, 3, 2, 3, 1, 10},
/* 10 01 10 01 */{4, 6, 9, 3, 2, 3, 2, 11},
/* 10 01 10 10 */{4, 6, 9, 3, 2, 3, 3, 12},
/* 10 01 10 11 */{4, 6, 9, 3, 2, 3, 4, 13},
/* 10 01 11 00 */{4, 6, 10, 3, 2, 4, 1, 11},
/* 10 01 11 01 */{4, 6, 10, 3, 2, 4, 2, 12},
/* 10 01 11 10 */{4, 6, 10, 3, 2, 4, 3, 13},
/* 10 01 11 11 */{4, 6, 10, 3, 2, 4, 4, 14},
/* 10 10 00 00 */{4, 7, 8, 3, 3, 1, 1, 9},
/* 10 10 00 01 */{4, 7, 8, 3, 3, 1, 2, 10},
/* 10 10 00 10 */{4, 7, 8, 3, 3, 1, 3, 11},
/* 10 10 00 11 */{4, 7, 8, 3, 3, 1, 4, 12},
/* 10 10 01 00 */{4, 7, 9, 3, 3, 2, 1, 10},
/* 10 10 01 01 */{4, 7, 9, 3, 3, 2, 2, 11},
/* 10 10 01 10 */{4, 7, 9, 3, 3, 2, 3, 12},
/* 10 10 01 11 */{4, 7, 9, 3, 3, 2, 4, 13},
/* 10 10 10 00 */{4, 7, 10, 3, 3, 3, 1, 11},
/* 10 10 10 01 */{4, 7, 10, 3, 3, 3, 2, 12},
/* 10 10 10 10 */{4, 7, 10, 3, 3, 3, 3, 13},
/* 10 10 10 11 */{4, 7, 10, 3, 3, 3, 4, 14},
/* 10 10 11 00 */{4, 7, 11, 3, 3, 4, 1, 12},
/* 10 10 11 01 */{4, 7, 11, 3, 3, 4, 2, 13},
/* 10 10 11 10 */{4, 7, 11, 3, 3, 4, 3, 14},
/* 10 10 11 11 */{4, 7, 11, 3, 3, 4, 4, 15},
/* 10 11 00 00 */{4, 8, 9, 3, 4, 1, 1, 10},
/* 10 11 00 01 */{4, 8, 9, 3, 4, 1, 2, 11},
/* 10 11 00 10 */{4, 8, 9, 3, 4, 1, 3, 12},
/* 10 11 00 11 */{4, 8, 9, 3, 4, 1, 4, 13},
/* 10 11 01 00 */{4, 8, 10, 3, 4, 2, 1, 11},
/* 10 11 01 01 */{4, 8, 10, 3, 4, 2, 2, 12},
/* 10 11 01 10 */{4, 8, 10, 3, 4, 2, 3, 13},
/* 10 11 01 11 */{4, 8, 10, 3, 4, 2, 4, 14},
/* 10 11 10 00 */{4, 8, 11, 3, 4, 3, 1, 12},
/* 10 11 10 01 */{4, 8, 11, 3, 4, 3, 2, 13},
/* 10 11 10 10 */{4, 8, 11, 3, 4, 3, 3, 14},
/* 10 11 10 11 */{4, 8, 11, 3, 4, 3, 4, 15},
/* 10 11 11 00 */{4, 8, 12, 3, 4, 4, 1, 13},
/* 10 11 11 01 */{4, 8, 12, 3, 4, 4, 2, 14},
/* 10 11 11 10 */{4, 8, 12, 3, 4, 4, 3, 15},
/* 10 11 11 11 */{4, 8, 12, 3, 4, 4, 4, 16},
/* 11 00 00 00 */{5, 6, 7, 4, 1, 1, 1, 8},
/* 11 00 00 01 */{5, 6, 7, 4, 1, 1, 2, 9},
/* 11 00 00 10 */{5, 6, 7, 4, 1, 1, 3, 10},
/* 11 00 00 11 */{5, 6, 7, 4, 1, 1, 4, 11},
/* 11 00 01 00 */{5, 6, 8, 4, 1, 2, 1, 9},
/* 11 00 01 01 */{5, 6, 8, 4, 1, 2, 2, 10},
/* 11 00 01 10 */{5, 6, 8, 4, 1, 2, 3, 11},
/* 11 00 01 11 */{5, 6, 8, 4, 1, 2, 4, 12},
/* 11 00 10 00 */{5, 6, 9, 4, 1, 3, 1, 10},
/* 11 00 10 01 */{5, 6, 9, 4, 1, 3, 2, 11},
/* 11 00 10 10 */{5, 6, 9, 4, 1, 3, 3, 12},
/* 11 00 10 11 */{5, 6, 9, 4, 1, 3, 4, 13},
/* 11 00 11 00 */{5, 6, 10, 4, 1, 4, 1, 11},
/* 11 00 11 01 */{5, 6, 10, 4, 1, 4, 2, 12},
/* 11 00 11 10 */{5, 6, 10, 4, 1, 4, 3, 13},
/* 11 00 11 11 */{5, 6, 10, 4, 1, 4, 4, 14},
/* 11 01 00 00 */{5, 7, 8, 4, 2, 1, 1, 9},
/* 11 01 00 01 */{5, 7, 8, 4, 2, 1, 2, 10},
/* 11 01 00 10 */{5, 7, 8, 4, 2, 1, 3, 11},
/* 11 01 00 11 */{5, 7, 8, 4, 2, 1, 4, 12},
/* 11 01 01 00 */{5, 7, 9, 4, 2, 2, 1, 10},
/* 11 01 01 01 */{5, 7, 9, 4, 2, 2, 2, 11},
/* 11 01 01 10 */{5, 7, 9, 4, 2, 2, 3, 12},
/* 11 01 01 11 */{5, 7, 9, 4, 2, 2, 4, 13},
/* 11 01 10 00 */{5, 7, 10, 4, 2, 3, 1, 11},
/* 11 01 10 01 */{5, 7, 10, 4, 2, 3, 2, 12},
/* 11 01 10 10 */{5, 7, 10, 4, 2, 3, 3, 13},
/* 11 01 10 11 */{5, 7, 10, 4, 2, 3, 4, 14},
/* 11 01 11 00 */{5, 7, 11, 4, 2, 4, 1, 12},
/* 11 01 11 01 */{5, 7, 11, 4, 2, 4, 2, 13},
/* 11 01 11 10 */{5, 7, 11, 4, 2, 4, 3, 14},
/* 11 01 11 11 */{5, 7, 11, 4, 2, 4, 4, 15},
/* 11 10 00 00 */{5, 8, 9, 4, 3, 1, 1, 10},
/* 11 10 00 01 */{5, 8, 9, 4, 3, 1, 2, 11},
/* 11 10 00 10 */{5, 8, 9, 4, 3, 1, 3, 12},
/* 11 10 00 11 */{5, 8, 9, 4, 3, 1, 4, 13},
/* 11 10 01 00 */{5, 8, 10, 4, 3, 2, 1, 11},
/* 11 10 01 01 */{5, 8, 10, 4, 3, 2, 2, 12},
/* 11 10 01 10 */{5, 8, 10, 4, 3, 2, 3, 13},
/* 11 10 01 11 */{5, 8, 10, 4, 3, 2, 4, 14},
/* 11 10 10 00 */{5, 8, 11, 4, 3, 3, 1, 12},
/* 11 10 10 01 */{5, 8, 11, 4, 3, 3, 2, 13},
/* 11 10 10 10 */{5, 8, 11, 4, 3, 3, 3, 14},
/* 11 10 10 11 */{5, 8, 11, 4, 3, 3, 4, 15},
/* 11 10 11 00 */{5, 8, 12, 4, 3, 4, 1, 13},
/* 11 10 11 01 */{5, 8, 12, 4, 3, 4, 2, 14},
/* 11 10 11 10 */{5, 8, 12, 4, 3, 4, 3, 15},
/* 11 10 11 11 */{5, 8, 12, 4, 3, 4, 4, 16},
/* 11 11 00 00 */{5, 9, 10, 4, 4, 1, 1, 11},
/* 11 11 00 01 */{5, 9, 10, 4, 4, 1, 2, 12},
/* 11 11 00 10 */{5, 9, 10, 4, 4, 1, 3, 13},
/* 11 11 00 11 */{5, 9, 10, 4, 4, 1, 4, 14},
/* 11 11 01 00 */{5, 9, 11, 4, 4, 2, 1, 12},
/* 11 11 01 01 */{5, 9, 11, 4, 4, 2, 2, 13},
/* 11 11 01 10 */{5, 9, 11, 4, 4, 2, 3, 14},
/* 11 11 01 11 */{5, 9, 11, 4, 4, 2, 4, 15},
/* 11 11 10 00 */{5, 9, 12, 4, 4, 3, 1, 13},
/* 11 11 10 01 */{5, 9, 12, 4, 4, 3, 2, 14},
/* 11 11 10 10 */{5, 9, 12, 4, 4, 3, 3, 15},
/* 11 11 10 11 */{5, 9, 12, 4, 4, 3, 4, 16},
/* 11 11 11 00 */{5, 9, 13, 4, 4, 4, 1, 14},
/* 11 11 11 01 */{5, 9, 13, 4, 4, 4, 2, 15},
/* 11 11 11 10 */{5, 9, 13, 4, 4, 4, 3, 16},
/* 11 11 11 11 */{5, 9, 13, 4, 4, 4, 4, 17}
};
/**
* 一次编码4个int
* @param values
* @param target
* @param start
* @return bytes数组的下一个下标地址
*/
static int groupVarintEncodeInt(final int[] values, int vstat, byte[] target, int tstart)
{
int val1 = values[vstat+0];
int val2 = values[vstat+1];
int val3 = values[vstat+2];
int val4 = values[vstat+3];
int idx = tstart + 1;
byte len1 = intToBytes(val1, target, idx);
byte len = len1;
byte len2 = intToBytes(val2, target, idx + len);
len += len2;
byte len3 = intToBytes(val3, target, idx + len);
len += len3;
byte len4 = intToBytes(val4, target, idx + len);
len += len4;
/* 处理第一个索引字节 */
target[tstart] = (byte) (((len1 - 1) << 6) | ((len2 - 1) << 4) | ((len3 - 1) << 2) | (len4 - 1));
return idx + len;
}
/**
*
* @param buf
* @param start
* @param values
* @return
*/
public static int groupVarintDecodeInt32 ( byte[] target, int tstart, int[] values, int vstart)
{
int idx = (target[tstart] > 0 ? target[tstart] : target[tstart] + 256);
//int idx = Math.abs(target[0]);
int start1 = tstart + 1;
int start2 = tstart + GROUP_VARINT_IDX_ARR[idx][0];
int start3 = tstart + GROUP_VARINT_IDX_ARR[idx][1];
int start4 = tstart + GROUP_VARINT_IDX_ARR[idx][2];
values[vstart] = intFromBytes(target, start1, GROUP_VARINT_IDX_ARR[idx][3]);
values[vstart+1] = intFromBytes(target, start2, GROUP_VARINT_IDX_ARR[idx][4]);
values[vstart+2] = intFromBytes(target, start3, GROUP_VARINT_IDX_ARR[idx][5]);
values[vstart+3] = intFromBytes(target, start4, GROUP_VARINT_IDX_ARR[idx][6]);
return tstart + GROUP_VARINT_IDX_ARR[ idx ][ 7 ];
}
private static final byte intToBytes(int value, byte[] target, int start) {
byte len = 0;
if (value > UINT24_MAX ){
len = 4;
}else if ( value > UINT16_MAX ){
len = 3;
}else if ( value > UINT8_MAX ){
len = 2;
}else{
len = 1;
}
unsafe.putInt(target, BYTE_ARRAY_OFFSET + start, value);
return len;
}
private final static int[] x = {
0, 0xFF, 0xFFFF, 0xFFFFFF, 0xFFFFFFFF
};
private static final int intFromBytes(byte[] source, int start, int count) {
int value = unsafe.getInt(source, BYTE_ARRAY_OFFSET + start);
value &= x[count];
/*
int value = 0;
for (int i = 0; i < count; i++) {
if (source[start+i] < 0) {
value += ((int)source[start+i] + 256);
}else {
value += (source[start+i] << i*8);
}
}
*/
/*
int value = source[start];
if (count > 1) {
for (int i = 1; i < count; i++) {
if (source[start+i] < 0) {
value |= (source[start+i]+256) << (i*8);
}else {
value |= (source[start+i] << i*8);
}
}
}
*/
return value;
}
/**
* 有符号数编码为无符号数
* @param n
* @return
*/
public static int zigZagEncodeInt(int n) {
return ((n << 1) ^ (n >> 31));
}
public static long zigZagEncodeLong(long n) {
return ((n << 1) ^ (n >> 63));
}
/**
* 无符号数解码为有符号数
* @param n
* @return
*/
public static int zigZagDecodeInt(int n) {
return (n >>> 1) ^ -(n & 1);
}
public static long zigZagDecodeLong(long n) {
return (n >>> 1) ^ -(n & 1);
}
public static void main(String[] args) {
int count = 1000000;
int[] raw = new int[count];
byte[] target = new byte[count*5];
int[] newInt = new int[count];
Random random = new Random();
for (int i = 0; i < count; i++) {
raw[i] = random.nextInt(count);
//raw[i] = 255000000+i;
}
long startTime = System.nanoTime();
int tstart = 0;
for (int i = 0; i < count / 4; i++) {
tstart = groupVarintEncodeInt(raw, i*4, target, tstart);
}
System.out.println("encode " + count + " ints, using=>" + (System.nanoTime() - startTime) + "ns");
startTime = System.nanoTime();
tstart = 0;
for (int i = 0; i < count / 4; i++) {
tstart = groupVarintDecodeInt32 (target, tstart, newInt, i * 4);
}
System.out.println("decode " + count + " ints, using=>" + (System.nanoTime() - startTime) + "ns");
for (int i = 0; i < count; i++) {
if (raw[i] != newInt[i]) {
System.out.println("error=> " + i + " raw[i]=>" + raw[i] + " newInt[i]=>" + newInt[i]);
break;
}
}
System.out.println("ok");
}
}