public static String readString()

in openAPI/src/main/java/jetbrains/exodus/bindings/BindingUtils.java [59:106]
48 lines of code
13 McCabe index (conditional complexity)

    public static String readString(@NotNull final ByteArrayInputStream stream) {
        int next = stream.read();
        if (next == UTFUtil.NULL_STRING_UTF_VALUE) {
            next = stream.read();
            if (next == 0) {
                return null;
            }
            throw new IllegalArgumentException();
        }
        if (next == 0) {
            return "";
        }
        if (!(stream instanceof ByteArraySizedInputStream)) {
            throw new IllegalArgumentException("ByteArraySizedInputStream is expected");
        }
        final ByteArraySizedInputStream sizedStream = (ByteArraySizedInputStream) stream;
        final byte[] bytes = sizedStream.toByteArray();
        final char[] chars = new char[sizedStream.size() - 1]; // minus trailing zero
        int i = sizedStream.pos();
        int j = 0;
        do {
            if (next < 128) {
                chars[j++] = (char) next;
            } else {
                final int high = next >> 4;
                if (high == 12 || high == 13) {
                    final int char2 = bytes[i++] & 0xff;
                    if ((char2 & 0xC0) != 0x80) {
                        throw new IllegalArgumentException();
                    }
                    chars[j++] = (char) (((next & 0x1F) << 6) | (char2 & 0x3F));
                } else if (high == 14) {
                    final int char2 = bytes[i] & 0xff;
                    final int char3 = bytes[i + 1] & 0xff;
                    i += 2;
                    if (((char2 & 0xC0) != 0x80) || ((char3 & 0xC0) != 0x80)) {
                        throw new IllegalArgumentException();
                    }
                    chars[j++] = (char) (((next & 0x0F) << 12) | ((char2 & 0x3F) << 6) | ((char3 & 0x3F)));
                } else {
                    throw new IllegalArgumentException();
                }
            }
            next = bytes[i++] & 0xff;
        } while (next != 0);
        sizedStream.setPos(i);
        return new String(chars, 0, j);
    }