java - byte to string and vice versa

Question

I need to convert a salt value randomly generated and store it in the database. To store it in the database I converted it to a string. Then for retrieving the original value, I convert it back to byte. But both value are not matching. I have tried "UTF-8","UTF-16", BASE64Encoder.

SecureRandom ranGen = new SecureRandom();
byte[] aesKey = new byte[16]; // 16 bytes = 128 bits
ranGen.nextBytes(aesKey);   
System.out.println(aesKey);

String a=new String(aesKey,"UTF-16");
byte[] b=new byte[16];
b=a.getBytes("UTF-16");
System.out.println(b);

Outputs for the above code(Executed it 2 times):

[B@11563ff
[B@1581593

and

[B@170888e
[B@11563ff

Answer 1

You really ought to use Base64 for converting binary data to Strings. There are lots of free implementations available, for example the one found in Apache Commons Codec.

Also, it's really easy to use, for example:

For encoding:

import org.apache.commons.codec.binary.Base64;
...
byte[] abValue = {...}; // Your data to encode
Base64 base64 = new Base64();
String strEncodedData = base64.encodeToString(abValue).trim();

For decoding:

import org.apache.commons.codec.binary.Base64;
...
String strEncodedData = "..."; // Your previously encoded data
Base64 base64 = new Base64();
byte[] abValue = base64.decode(strValue);