[
https://issues.apache.org/jira/browse/CODEC-96?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13234003#comment-13234003
]
Sebb commented on CODEC-96:
---------------------------
I've got a prototype which passes all the tests.
Basically I put all the mutable fields in a Context class which is created by
the appropriate stream classes and public methods. This allows the BaseN
classes to be immutable i.e. threadsafe.
Clirr reports several incompatibilities because I moved all the protected
mutable fields into the context.
However, these are protected fields, and are not really intended for use by
external code, so it's very unlikely to cause problems. I did not need to
change the test code (except where it was overriding or testing
package-protected methods), which is a good sign.
See attachment to follow.
> Base64 encode() method is no longer thread-safe, breaking clients using it as
> a shared BinaryEncoder
> ----------------------------------------------------------------------------------------------------
>
> Key: CODEC-96
> URL: https://issues.apache.org/jira/browse/CODEC-96
> Project: Commons Codec
> Issue Type: Bug
> Affects Versions: 1.4
> Reporter: Matt Ryall
> Assignee: Julius Davies
> Fix For: 1.x
>
> Attachments: codec-96-3rd-attempt.patch
>
>
> Streaming support was added to Base64 in commons-codec 1.4 with CODEC-69.
> This introduced instance variables to Base64 which means the class can no
> longer be used as a shared BinaryEncoder instance.
> For example, BinaryEncoder has an interface which could be (and was) used
> like this with Base64:
> {code:java}
> class Example {
> private BinaryEncoder encoder = new Base64();
> byte[] someMethod(byte[] data) {
> try {
> return encoder.encode(data);
> }
> catch (EncoderException e) {
> throw new RuntimeException(e);
> }
> }
> }
> {code}
> Base64 is no longer thread-safe in commons-codec 1.4, so code like the above
> which is accessed by multiple threads can throw NullPointerException:
> {noformat}
> java.lang.NullPointerException
> at org.apache.commons.codec.binary.Base64.encode(Base64.java:469)
> at org.apache.commons.codec.binary.Base64.encode(Base64.java:937)
> at ... (application code)
> {noformat}
> Looking at the implementation of Base64, I think making it thread-safe for
> this kind of usage would be quite tricky. I haven't attempted to prepare a
> patch.
> I would be happy if it was indicated in the Javadoc that Base64 is not
> thread-safe and should not be shared. However, some other users of
> commons-codec might be more worried about this regression.
--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators:
https://issues.apache.org/jira/secure/ContactAdministrators!default.jspa
For more information on JIRA, see: http://www.atlassian.com/software/jira
