Java 21 is proposed as a long term support (LTS) release and hence we expect companies to adopt Java 21 soon. We have been hearing about Patterns for a long time, and now we have Java 21 which would have Pattern Switches as a standard feature. Additionally, Record Patterns is another pattern feature. Used together, these two provide a powerful programming tool, which now we can use in production, since these two features for the first time will be available as standard features in Java 21. Additionally, the feature of Unnammed Patterns is also expected to join the Pattern features list. Apart from pattern features, another significant feature is the String Templates which has been pending for sometime. This is a feature that is expected to be used very widely.
It has to be noted that the standard features are not a direct move from preview as it is. There are significant changes that happened over the last few releases to have the standard features in the current avatar. Talk will touch upon some of these aspects as well. Having implemented these features, with the team, will touch upon some of the insights over the historical development of these features as well. As usual, talk would also take a peek at the near future as to how these patterns would be used. Again, as is the tradition, will be covering the features in some detail alongwith a brief discussion of byte code changes as applicable - however, the discussion would just provide what an "ordinary" Java programmer would require and not for the byte-code-anlayser programmer. I may touch upon the non-compiler part of JDT only on a need basis for these features without delving too much into the details leaving that scope for another session.
Java 21 features would include Patterns - Pattern Switches, Record Patterns, Unnammed Patterns, String Templates - time permitting, may touch upon additional features as well. Attendees are expected to have some prior programming experience with Java and no other pre-requisite is expected. After attending the session, attendees would have an overall understanding of the features discussed and would have an idea as to how and when to use them.
