public void putUtf8String(String value) {
        byte[] stringBytes = Utf8.toBytes(value);
        putInt1_4Bytes(stringBytes.length);
        put(stringBytes);
    }
Writes this string to the buffer as a 1_4 encoded length in bytes followed by the utf8 bytes
vespajlib/src/main/java/com/yahoo/io/GrowableByteBuffer.java