This is the last session I plan on attending today, and it's titled "Experiences with the 1.5 Language Features: Tips and Techniques" by Tim Hanson and Jess Garms of BEA. Tonight looks to be a good time with the JBoss Party, Java Blogger Meetup (@ Thirsty Bear), the Pavilion Party. Times for the events are 5-9, 6-8 and 6:30-8. This conference is definitely packed, and I expect the parties to be the same. In other words, the best part of this shindig is yet to begin.
This talk is about how to make effective use of the new 1.5 Language Features in your applications.
For Each Loop: Initialization expression is evaluated once (unlike former). Major limitation of using the new for each loop is you don't have access to the index or the iterator.
Annotations: Built-in annotations - i.e. @SuppressWarnings("deprecation"). Possible values: all, deprecation, unchecked, fallthrough, path, serial, finally. This annotation is not supported in the latest version of Java 5, it is supported in Mustang and Eclipse 3.1. @Deprecated is another built-in annotations. If you use this tag, you should use the @deprecated javadoc tag as well. Last one is @Override, which is used to indicate that a method declaration is intended to override a method declaration in a superclass. If the superclass signature changes, this annotation will make sure you change it in child classes.
Annotations are especially useful for frameworks (i.e. EJBs, Web Services, etc.). Not a preprocessor, not a silver bullet.
Enums: Better than static final int. Type-safe. Utility classes: java.util.EnumMap and EnumSet. Public static final int-like behavior: Comparable, statically importable (even as an inner class).
Varargs: Special syntax for cleaning up code. Allows you to use "String... args" instead of a whole slew of methods that take multiple arguments. Use them sparingly - avoid code that casts.
Covariant Returns: Replaces three anti-patterns.
Using Generics: Example from Collections - static List Collections.singletonList(T o). There is a two-pass inferencing process to determine what T is. Other Generified classes: Class (public T newInstance()), Comparable (public int compareTo(T o)), Enum> (public Class getDeclaringClass()). You can also use wildcards with generics, which has a syntax of List extends Number> instead of List. This allows you to specify subtypes, and not be tied to a strictly typed solution. Wildcards are great to use in APIs and to hide implementations from users.
I give up - this guy has been going on about Generics for far too long. Time to go hunt down some parties.
I'm sitting in a session titled "Yet More Programming Puzzlers" by Joshua Block and Neal Gafter. The other two sessions I chose for this time slot were Groovy and EJB 3. The main reason I chose this session is I've seen these guys in action before and they're excellent speakers. As part of this conference, I'd like to learn a bit about technology - but I'm more interested in becoming a better speaker. This is only my second of the day, with the first being the general session this morning. The afternoon has been spent networking, doing some Virtuas booth time, and presentation a short talk on AppFuse on the java.net booth.
In other news, it's pretty cool to see that BEA is going to start supporting Spring and Struts in its tools and servers.
The BEA WebLogic Workshop and other tools will be designed to
allow applications to be built or blended from leading open source
frameworks, including Apache Beehive, the Spring Framework and Apache
Struts, and can then be deployed on BEA WebLogic Server. BEA will
also certify the BEA WebLogic Workshop tools for Apache Geronimo and
Apache Tomcat.
The Google Guys session? Entertaining and packed. All chairs were filled and many people were standing in the back and on the sides.
I arrived in San Francisco at 8:30 this morning, and headed downtown to the Moscone center. I've been sitting in the "General Session" room for the last couple of hours, and there's been some interesting announcements. You can get a Sun Ultra 20 Workstation for $30/month and it comes with a 90-day money-back guarantee. The guy on stage made it sound like a screaming machine, but it was also a Sun sales pitch.
Another announcement is they're dropping the "2" from J2EE and J2SE. Now we're not supposed to say the "J", but rather "Java". Now it's called "Java EE". I think the 2 needed to be dropped, but I think it'll take a while before Java EE has the same ring as J2EE. I can already see folks calling it "Java, eh".