UUID高效去除短横线

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import java.util.UUID;

public class UUIDUtil {

    /**
     * 1111
     * 
     * all 1 in 16 hexadecimal
     */
    private static final long hexMod = 15L;
    /**
     * All possible chars for representing a number as a hex String
     */
    private static final char[] digits = new char[] { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f' };

    public static String toHexString(UUID uuid) {
        char[] array = new char[32];
        long leastBits = uuid.getLeastSignificantBits();
        for (int i = 31; i >= 16; i--) {
            array[i] = digits[(int) (leastBits & hexMod)];
            leastBits >>>= 4;
        }
        long mostBits = uuid.getMostSignificantBits();
        for (int i = 15; i >= 0; i--) {
            array[i] = digits[(int) (mostBits & hexMod)];
            mostBits >>>= 4;
        }
        return new String(array);
    }

    public static String randomUUID() {
        return toHexString(UUID.randomUUID());
    }

}

算法背景：

标准UUID的toString返回的字符串带有短横线，

UUID.randomUUID().toString();

引用

8b4e04f3-f68a-48c4-8c18-88c1f84530e5

使用replace方式去除短横线的效率不高。

UUID.randomUUID().toString().replace("-", "");

引用

8b4e04f3f68a48c48c1888c1f84530e5