Review request for 8035807: Convert use of sun.misc.BASE64Encoder/Decoder with java.util.Base64

[Vincent Ryan]

On 22 Mar 2014, at 03:22, Mandy Chung <mandy.chung at oracle.com> wrote:

> Good catch Sherman.
> 
> Vinnie - what's your recommendation for this LDAP change having both encode/decode uses the platform default charset (rather than retaining the old interop issue)?  It's an incompatible change and I'll file a CCC to track this.

Yes. I think that’s the right approach as the compatibility risk is low.


> 
> Mandy
> 
> On 3/21/2014 2:23 AM, Vincent Ryan wrote:
>> You’re right but we’ve never received a report of any charset interop. issues.
>> Probably such a scenario has never been encountered by customers.
>> 
>> 
>> On 21 Mar 2014, at 05:54, Xueming Shen <xueming.shen at oracle.com> wrote:
>> 
>>> Obj.java:#482
>>>    It appears sun.misc.BASE64Decoder.decodeBuffer(String) uses String's deprecated
>>>    String.getBytes(int srcBegin, int srcEnd, byte[] dst, int dstBegin). The proposed change
>>>    now uses the jvm's default charset. It might trigger incompatible behavior if the default
>>>    charset is not an ASCII compatible charset.  But if the "Java object in LDAP was encoded
>>>    with the platform default charset" (as the new comment suggested), the old implementation
>>>    actually did not work on platform that the default encoding is not ASCII compatible, such
>>>    as the IBM ebcdic.
>>> 
>>> -Sherman
>>> 
>>> On 3/20/14 3:48 PM, Mandy Chung wrote:
>>>> On 3/19/14 12:28 PM, Xueming Shen wrote:
>>>>> On 03/19/2014 11:37 AM, Mandy Chung wrote:
>>>>>> https://bugs.openjdk.java.net/browse/JDK-8035807
>>>>>> 
>>>>>> Webrev at:
>>>>>> http://cr.openjdk.java.net/~mchung/jdk9/webrevs/8035807/webrev.00/
>>>>>> 
>>>>>> This patch converts the last 2 references to sun.misc.BASE64Encoder/Decoder from the jdk repo with java.util.Base64.   We should also update the tests and I have filed JDK-8037873 for that.
>>>>>> 
>>>>>> Thanks
>>>>>> Mandy
>>>>> The sun.misc.BASE64En/Decoder is MIME type, so it outputs the \r\n per 76
>>>>> characters during encoding, and ignores/skip \r or \n when decoding. The new
>>>>> Base64.getEncoder/Decoder() returns the "basic" Base64 coder, which it never
>>>>> inserts line separator when output, and throws exception for any non-base64-
>>>>> alphabet character, including \r and \n.
>>>>> 
>>>>> The only disadvantage/incompatibility (j.u.Base64.getMimeDecoer() vs
>>>>> sun.misc.BASE64Decoder) of switching to j.u.Base64 MIME type en/decoder
>>>>> is that the Base64 Mime decoder ignores/skips any non-base64-alphabet
>>>>> (including \r and \n), while sun.misc.BASE64Decoder appears to simply
>>>>> use the init value "-1" for any non-base64-alphabet character for decoding.
>>>>> 
>>>>> I'm not familiar with the use scenario of ldap's Obj class, so I'm not sure if
>>>>> it matters (if it ever outputs/inputs > 76 character data, or even it does,if
>>>>> the difference matters).
>>>>> 
>>>>> Btw, except getMimeEncoder(int ...) all other Base64.getXXXEn/Decoder()
>>>>> returns singleton, so the de/encoder cache might not be necessary.
>>>> Thanks Sherman.  Vinnie confirms that it should retain the current behavior as there could be long-lived Java object in LDAP encoded with JDK 8 for example and then retrieved with JDK 9.
>>>> 
>>>> Here is the updated webrev:
>>>> http://cr.openjdk.java.net/~mchung/jdk9/webrevs/8035807/webrev.01/
>>>> 
>>>> Thanks
>>>> Mandy
>