jodd-core/src/main/java/jodd/util/Base64.java
public static byte[] decode(final char[] arr) {
		int length = arr.length;
		if (length == 0) {
			return new byte[0];
		}

		int sndx = 0, endx = length - 1;
		int pad = arr[endx] == '=' ? (arr[endx - 1] == '=' ? 2 : 1) : 0;
		int cnt = endx - sndx + 1;
		int sepCnt = length > 76 ? (arr[76] == '\r' ? cnt / 78 : 0) << 1 : 0;
		int len = ((cnt - sepCnt) * 6 >> 3) - pad;
		byte[] dest = new byte[len];

		int d = 0;
		for (int cc = 0, eLen = (len / 3) * 3; d < eLen;) {
			int i = INV[arr[sndx++]] << 18 | INV[arr[sndx++]] << 12 | INV[arr[sndx++]] << 6 | INV[arr[sndx++]];

			dest[d++] = (byte) (i >> 16);
			dest[d++] = (byte) (i >> 8);
			dest[d++] = (byte) i;

			if (sepCnt > 0 && ++cc == 19) {
				sndx += 2;
				cc = 0;
			}
		}

		if (d < len) {
			int i = 0;
			for (int j = 0; sndx <= endx - pad; j++) {
				i |= INV[arr[sndx++]] << (18 - j * 6);
			}
			for (int r = 16; d < len; r -= 8) {
				dest[d++] = (byte) (i >> r);
			}
		}

		return dest;
	}
public static byte[] decode(final char[] arr) {
		int length = arr.length;
		if (length == 0) {
			return new byte[0];
		}

		int sndx = 0, endx = length - 1;
		int pad = arr[endx] == '=' ? (arr[endx - 1] == '=' ? 2 : 1) : 0;
		int cnt = endx - sndx + 1;
		int sepCnt = length > 76 ? (arr[76] == '\r' ? cnt / 78 : 0) << 1 : 0;
		int len = ((cnt - sepCnt) * 6 >> 3) - pad;
		byte[] dest = new byte[len];

		int d = 0;
		for (int cc = 0, eLen = (len / 3) * 3; d < eLen;) {
			int i = INV[arr[sndx++]] << 18 | INV[arr[sndx++]] << 12 | INV[arr[sndx++]] << 6 | INV[arr[sndx++]];

			dest[d++] = (byte) (i >> 16);
			dest[d++] = (byte) (i >> 8);
			dest[d++] = (byte) i;

			if (sepCnt > 0 && ++cc == 19) {
				sndx += 2;
				cc = 0;
			}
		}

		if (d < len) {
			int i = 0;
			for (int j = 0; sndx <= endx - pad; j++) {
				i |= INV[arr[sndx++]] << (18 - j * 6);
			}
			for (int r = 16; d < len; r -= 8) {
				dest[d++] = (byte) (i >> r);
			}
		}

		return dest;
	}
Decodes a BASE64 encoded char array.