Java 5 RC Available, Gold Targeted for this Month

Trevor Leach writes "Sun's Java 5 download page is now serving up J2SE 5.0 RC. There are loads of productivity enhancements in this release, code named 'Tiger,' including generics, enums, autoboxing of primitive types, and metadata. Additionally, the Java Developer's Journal qoutes Sun's Graham Hamilton, chief technologist of Java Software, as specifying September 30 as Tiger's target release date."

Comments

Are people still using java?

[kiddygrinder]

Why would you want to use java? .Net is NEW! it's got MS on it! If you go by memory footprint it's way bigger and therefore better!

autoboxing ?

[BigBadDude]

why is autoboxing so darn important to some people??

i will probably never use it because if i want a hash-table of integers or a binary-tree of doubles, i will write it myself with the native types. it is faster, and eats less memory.

the whole idea of hiding complexity by converting int to Integer and vice versa automatically is kinda scareing.

not to mention the waste of memory for creating those stupid wrapper objects...

Re:autoboxing ?

[rmull]

Ways to measure time:
1) execution time
2) development time

1 is usually less important than 2. Really. If it saves me one round trip to the compiler, I'll take it. The merits of the boxes themselves aside, this is a very reasonable and useful thing to do, from the perspective of both ease of coding and of code clarity.

Re:autoboxing ?

[BigBadDude]

ok, wait.

how much time do you save for writting

int i = e.next();

instead of

Integer ii = (Integer)e.next();
int i = ii.intValue();

probably few mintues per working day. I am not sure if this makes you code more clear because most of the time when you put something in a List/Array/whatever, you want to change its value and you cant do that with an automatically boxed type:

e.next() ++;

will simple not do what you intended so you will have to go back to casting Integers again. now THIS mixed use of two different methods will make you coding unreadable.

Okay, nice, but...

[Elamaton]

Well, if I'm going to learn Java properly, this might be as good a time as any. So far I've only scratched the surface with some trivial GUI apps a year and a half ago. Sure looks like I need to know it if I want to get a programming job around here (at least in Finland, it's Java, VB, C++ or C#, or another line of work - which sucks since I'm currently a PHP/Python man myself; and of the given alternatives, I'm only interested in Java).

Getting a job would mean I'd have to learn J2EE as well (absolutely no one here is hiring plain J2SE people), and I honestly don't know how to go about it. Just looking at the TOC of Sun's J2EE tutorial is overwhelming with the enormous acronym soup, and judging by the articles I've read and by the quick glances I've taken at the types of literature available, learning it well seems to be nothing less than an impossible task.

I remember seeing a graph depicting the ever-increasing requirements of a typical J2EE programmer compared to the actual skill levels of the current programmers. The gap is huge and ever widening, and I just know I'd be just one more lousy underperforming J2EE guy with my insufficient knowledge. Is it practically possible to learn the stuff in any other way besides doing it for a living, moving on up slowly from basic J2SE? Anyone here taken the leap, and how?

I mean, you can't possibly know all that is J2EE properly. But what should one concentrate on, and roughly in what order? There's just TOO MUCH material, too many separate technologies, the practical purposes of which however overlap somewhat, and... I don't know, it's just too huge for my puny mind.

And to go with the topic of the front page post even slightly: what does the new release of Java mean in the context of J2EE programming? What, if any, portions of the existing literature and other material does the new release make obsolete? And for J2SE literature, is there any fresh stuff that would be written with Java 5 in mind?

Sigh... It's when things like this go through your mind that you wish you'd just be interested in something like plumbing as a career option, instead of programming. At least you'd always have work.

Re:Okay, nice, but...

[farnsworth]

J2EE is, by design, an enourmously complex API. I work with J2EE everyday, but almost no one I work with is good at more than about 50% of it.

Is it practically possible to learn the stuff in any other way besides doing it for a living, moving on up slowly from basic J2SE? Anyone here taken the leap, and how?

No, it's not. But that's not to say that you should not begin learning the API. J2EE covers HTTP...Server side web programming...Databases...Weird databases...Transactions...Distributed transactions...Distributed computing...Web services...Generated code...Annotated code...A ton of other stuff that I can't think of just this second.

That's a lot! No one can be very good at any of this stuff, nevermind all of this stuff. The best you can do is dig in and solve some real problems that you have. You wont learn much from reading Sun's tutorials unless you can honestly say, "oh wow! I never though of doing it this way..." and you can never say that unless you actually tried to something some other way. (Side note: Sun's documentation is notorious for being way way way over-the-top in terms of academic "correctness" vis a vis practically solving a problem.)

what should one concentrate on, and roughly in what order?

I would recomend starting with common tools, like Ant, log4j, Struts, Eclipse. Then move on to the actual API and specs of topics like JDBC, Servlet/Jsp, JMS, and familiarizing yourself with various EJB containers.

what does the new release of Java mean in the context of J2EE programming?

In reality? Nothing. It takes J2EE vendors a very long time to catch up with the latest and greatest JVM. At work, I'm still using 1.3.2. Even when container vendors release products that real companies buy, The differences between 1.3 and 1.4 and 1.5 are not that huge for a developer. There are lots of nice improvements, but nothing that you'll have a hard time with.

The bottom line is that if you can get good at a select few APIs, and are really really good at the tools, you'll have no problem ramping up on any of the other areas of J2EE.

Re:Okay, nice, but...

[Magnus Reftel]

mean, you can't possibly know all that is J2EE properly. But what should one concentrate on, and roughly in what order?

The only part of J2EE I've actually used my self as a Java programmer is the parts related to servlets. Since you say you use PHP, I take it you're not new to web projects. I'd recommend that you start there - download Tomcat, and learn JSP with taglibs & scriptlets. Then, gradualy move to a three-layer acrhitecture with chaining servlets and JSP for generating HTML only. (I learned PHP by rewriting my pet Servlet project in PHP, maybe the reverse could work for you?)

Ignore Java 5 for now - it usually takes quite a while for new Java versions to get used in production, especially with J2EE, where you pretty much have to wait for app servers to support new versions before you can even cosider using them yourself.

Re:Okay, nice, but...

[Scarblac]

I did one big J2EE project. We used Struts. There was one book that was very useful to me, and it's pretty short and affordable - _The Struts Framework: Practical Guide for Java Programmers_ by Sue Spielman. I can recommend it, it has a good overview and some details of all the little parts.

I learned what a servlet is and how it works from the Sun tutorials, I think. Using Struts you won't make many pure servlets but it's important to have basic knowledge of what happens. Do the tutorial. Same for JSPs (they get compiled to servlets, you can make a JSP, run it, and look at the source of the servlet, if you really want to).

We simply ran on Tomcat. Just install it and learn by online documentation. It of course has its pros and cons, but I can't really compare since I haven't used any other servers. It's a good start.

Of course, always keep Sun's API reference pages close.

As a layer between the OO Java parts and the database (MySQL in this case) we used a library called Torque. The idea is elegant and Torque is easy to learn, but it's slow and can become quite irritating. There are other options but I can't recall the names right now, and I think they are more complex.

I never did find out what an EJB is.

Oh, and these web apps can be hard to debug because of all the layers - setup Jython (a matter of putting the .jar somewhere and setting up the classpath correctly) so that you can call all your business code from a Python interactive prompt!

Re:Okay, nice, but...

[archeopterix]

Is it practically possible to learn the stuff in any other way besides doing it for a living, moving on up slowly from basic J2SE? Anyone here taken the leap, and how?

I took the leap from a very basic Java knowledge (some hello worlds) to J2EE. Some hints:

1. Motivation. Motivation helps. There's no motivation like being on an important project that uses J2EE, but this of course is usually beyond your control, unless you want to bluff your way into such a project (not recommended).

2. Books. Avoid learning anything from pure specs. The books that helped me: "Java Enterprise in a Nutshell" from O'Reilly (Nutshell my ass, that's the thickest book in my room). "Enterprise JavaBeans" from O'Reilly, "Bitter EJB" (can't grab it now, so no details).

3. Practice. I downloaded the Websphere Studio Application Developer (trial version) from IBM and started monkeying with it the moment I've heard about J2EE being used in the new project.

4. Forget the APIs (at least their details). Try to make a mental map of the most important stuff - Container, Client, Beans and how they relate to each other. Once you got that, you can fill the details like APIs & such.

Eclipse support

[HRbnjR]

This is great, but what I would really like to see, to make this useful for me, is support within Eclipse (it's parser/compiler chokes on 1.5 code features right now). And for those of you sharing my anticipation here is the bug from Eclipse's bugzilla for tracking the support.

Re:One things Java needs...

[ja]

I have NOT looked at RC 5, but hope they have either sped up SWING...

Linux and Solaris users, and new in beta2, Windows users, who have the latest OpenGL drivers and select graphic cards can get native hardware acceleration from Java2D using the following runtime property:

java -Dsun.java2d.opengl=true -jar Java2D.jar

mvh // Jens M Andreasen

Re:Remember when C# came out...

[GCP]

most of the stuff you mentioned had been planned to be included in the next releases of java long long time before C# was born.

No, it wasn't. It's not that Sun had never considered these features. They had considered them and rejected (most of) them.

As long as there was no direct competition, Sun was famous for repeatedly informing developers (like me) who requested most of these things that they "didn't get it" and that they knew what we really needed better than we did, and we didn't need these things. They talked about "language stability" and how extreme the circumstances would have to be to get them to make any change in the Java language, which had undergone no changes since 1.1.

Well, that "extreme circumstance" was serious competition in the form of C#. When Sun claims that they are not copying C# they are correct in the sense that they didn't have to be shown *how* to do these things, but without C# they would have gone on telling us "no" for a very long time.

More useful links

[prat393]

If you feel like a more in-detail look at 1.5, these documents might be useful:

• J2SE 5 New Features
• JDK 5.0 Release Notes (warning: not updated for the release candidate)