NibbleUtils.java revision 064d77c3ad2869aeb34f012f997e054e779e0a29 
1/*
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30 */
31
32package org.jf.util;
33
34public abstract class NibbleUtils {
35    /**
36     * Extracts the high signed 4-bit nibble from the least significant
37     * byte of the given value
38     * @param value the value to extract the nibble from
39     * @return the extracted signed nibble value
40     */
41    public static int extractHighSignedNibble(int value) {
42        return (value << 24) >> 28;
43    }
44
45    /**
46     * Extracts the low signed 4-bit nibble from the least significant
47     * byte of the given value
48     * @param value the value to extract the nibble from
49     * @return the extracted signed nibble value
50     */
51    public static int extractLowSignedNibble(int value) {
52        return (value << 28) >> 28;
53    }
54
55    /**
56     * Extracts the high unsigned 4-bit nibble from the least significant
57     * byte of the given value
58     * @param value the value to extract the nibble from
59     * @return the extracted unsigned nibble value
60     */
61    public static int extractHighUnsignedNibble(int value) {
62        return (value & 0xF0) >>> 4;
63    }
64
65    /**
66     * Extracts the low unsigned 4-bit nibble from the least significant
67     * byte of the given value
68     * @param value the value to extract the nibble from
69     * @return the extracted unsigned nibble value
70     */
71    public static int extractLowUnsignedNibble(int value) {
72        return value & 0x0F;
73    }
74}
75