使用字符串而不是字节数组java

Question

Can I use string instead array of bytes made with new String(bytes)? I whant to save them to database. In bytes I have calculated md5 hash.

Answer 1

No, a String is not suitable as a container for arbitrary bytes.

The String(byte[] bytes) constructor will interpret the array that you pass to it and convert it to characters, using the default character encoding of your system. This might throw an exception if the byte array contains a sequence of bytes which is not valid for the character encoding, and even if it works without an exception then calling getBytes() on the String is not guaranteed to return the exact same bytes.

If you want to store a byte array in a database, store it as a BLOB (Binary Large OBject), or, if you really want to store it as a string, then convert it into text using for example Base64 encoding or as hexadecimal digits.