A couple of weeks ago I wrote a summary of 7 new cool features in Java 7. Others have written great blog posts about them, so I was thinking it might be useful for me to focus on lesser known or “Hidden Java 7 Features”. In the next few weeks, I’ll try to explore and write a series of blog posts about them.

System and Process CPU Load Monitoring

Java 7 provides a new MBean that finally allows Java developers to access overall System and current process CPU load monitoring. This feature is not really that hidden as it’s listed in the what’s new page for JDK 7, but I haven’t really noticed a lot of talk about it and I certainly overlooked it initially.

The interface com.sun.management.OperatingSystemMXBean, has two new methods that easily get this information; getSystemCpuLoad() and getProcessCpuLoad(). Both methods return the load as a double value in the [0.0,1.0] interval, with 0.0 representing no load to 1.0 representing 100% CPU load for the whole system or the current JVM process respectively.

It’s pretty easy to get access to this MBean;

import com.sun.management.OperatingSystemMXBean;
...
OperatingSystemMXBean osBean = ManagementFactory.getPlatformMXBean(
                OperatingSystemMXBean.class);
// What % CPU load this current JVM is taking, from 0.0-1.0
System.out.println(osBean.getProcessCpuLoad());

// What % load the overall system is at, from 0.0-1.0
System.out.println(osBean.getSystemCpuLoad());

Wasn’t this already available?
Java 6 introduced a new method in java.lang.management.OperatingSystemMXBean called getSystemLoadAverage(), which could get the CPU average for the overall system (there wasn’t a mechanism for the JVM/current process load). However this doesn’t seem to work on Windows and would just return a -1 (tried this with Java 7 in Windows 7 and that is still the case).

Other ways of doing this prior to Java 7 would include Java APIs implemented via native libraries like SIGAR, which are good alternatives but obviously not part of the standard Java distribution, or may not support most platforms.

Now the bad news
If you notice in my code I use com.sun.management.OperatingSystemMXBean, not java.lang.management.OperatingSystemMXBean which means the methods getSystemCpuLoad() and getProcessCpuLoad() are not part of the official, supported public interface of the Java Platform. Oracle actually discourages the use of these packages, since they could be removed in future releases or may not be available in all JVM implementations.

I’m not 100% sure why these methods were only added to the com.sun version of OperatingSystemMXBean. Initially I thought it was because Oracle didn’t want to add a method to a public interface (which would break any code implementing that interface), however Java 6 added getSystemLoadAverage(). If anybody has any insight on this, please let me know.

There are ways to use these new methods without having a hard dependency to these com.sun classes (for example via reflection, or using JMX conventions), I may cover these in a future blog post or update to this one.

Demo, JCPUMon
Finally, I wanted to do a simple UI that would use this feature to have a little widget to monitor system CPU and current process load graphically. I call it “JCPMon”, it can be launched as a standalone Java application, run inside an application you want to monitor or just used as a Swing component in a Java UI.

The green part of the graph represents the overall system CPU load, while the yellow part represents the current process load, in this case CPU load imposed by the GUI (I did a lot of resizing to get a few yellow bars for this image ). If you want to monitor a Java application you already have, you can easily do so by calling;

// This method won't block, so you can call it at the start of your program
com.sellmic.apps.monitoring.jcpumon.Main(null);

// And then continue doing anything else ...

Of course an improvement would be to have the ability to connect to an external process via JMX (remote or local).

You can launch this app via webstart, .You’ll need Java 7 to be installed.

This simple GUI uses this new Java 7 capability and also has some extras to configure the look of the UI (squares or circles, size, how often to update, always on top, full screen). If anybody is interested in the code for this let me know and I can setup a page to host it.

UPDATE: JNLP URL was wrong, if you tried webstart before and it failed please try again. Sorry about that!

JavaOne officially starts tomorrow but today Sun has kicked off CommunityOne. Which is a more open source focused and free conference that precedes the bigger event.

The main theme this year is cloud computing. The presentation today has been about showing several vendor solutions in the areas of virtualization and large scale application deployment that is very easy to use (and graphical). To be completely honest, I think “cloud computing” is a big buzzword approaching marketroid levels, but there is some interesting technology here. I’ll be attending a few cloud computing sessions to see if I become one of the converted.

Currently, we’re listening to some of the folks from OpenSolaris and JavaFX in a setup that seems like a nerd version of David Letterman from an alternate reality.

BTW we got a small announcement that JavaFX is now officially released for OpenSolaris. Although I’m not sure there’s a large community of OpenSolaris users looking forward to that

At one point it was Apple, then IBM was supposed to be it more than a couple of times, well the buyer of Sun ends up being Oracle and I think this is a good thing.

First of all (and related to that panel from Watchmen), I was getting a little anxious about all this merger talk and wished it was done with. It’s difficult for a company to be under merger talks for too long, and as a user of a lot of Sun technologies it makes you nervous. So I’m glad this seems to be over with.

Anyways, I think ithis is better than the IBM-Sun (BlueSun) merger because it just didn’t make much sense for IBM to buy Sun. They overlap too much on hardware and software, and I was afraid IBM was just going to buy it to finally kill off a hardware competitor and just take ownership of Java. With Oracle, you still have IBM as a strong Java player and Sun actually brings a lot of new things to Oracle.

Yes, there are overlaps, but there’s a bigger chance for projects like Netbeans to survive under this environment than in a company with IBM which would rather keep putting money on Eclipse.

What I wonder about is these products:

JavaFX - Does Oracle really have the stomach to compete in the client space? I’m hoping they have the guts to keep at it and not settle only on the server side. Client side Java is still important, and makes sense when you want to have very well integrated tools that go from end to end. As for mobile, who knows, maybe Oracle wants to expand.

Glassfish - Can Glassfish survive in a company that uses WebLogic. I think so, at least initially or for the short term. Glassfish can still be used as the “JEE” reference implementation, so there is a chance Glassfish can still continue being a supported project.

MySQL - I’m not really sure Oracle wil want to keep spending money on this for obvious reasons. But who knows. Anyways, MySQL is open source so it can’t really be killed in a sense.

So I’m glad the speculation is over, good luck to all the Sun employees during this transition. This year should prove to be a very interesting and surreal JavaOne!

An article on treehugger has an interview with Paul Kim, VP of marketing for the Mozilla Corporation. The Mozilla marketing folks have decided to coin the term “organic software” in order to raise awareness of some of the other benefits of Mozilla besides its list of features.

Here is Paul’s rationale for using this term:

PK: I should clarify that we’re not trying to create a new model. Instead, what we’re trying to do is to help new sets of people who know nothing about open source software quickly start to understand that Firefox is something different from the software they’re currently using to access the Web. ‘Organic software’ is a concept we came up with that we thought would resonate with end users in ways that ‘free software’ doesn’t. I think ‘free software’, at least in the US, doesn’t carry the same valence that ‘FLOSS‘ does in, say, Europe.

PK: I think for people in the open source movement, the term ‘organic’ is a lot clearer and immediately graspable. I think in the broader culture, and again I’m speaking of the US, the word ‘free’ gets filtered through a consumer lens. So yes, it’s a terminology issue for end users – trying to communicate clearly what practitioners already grok.

I appreciate what the Mozilla folks are trying to do here, but this whole campaign seems wrongheaded and actually misleading. The term organic is often associated with organic food, which is supposed to be healthier and friendlier to the environment. That is acknowledged in the article. Using this term causes more confusion in my mind, when I first read it, I thought the Mozilla developers were making a “green” commitment and trying to save the environment by changing some of their habits (perhaps turn off their computers once in a while?).

What they should do is keep educating the public on the term “open source” instead of confusing the issue further. Their uses further overloads the word “organic” and I can also see companies jumping on the bandwagon and redefining the whole definition (ex: A software company pledges to go “green” and calls their software organic).

The article itself is proof of what I’m saying. It is from a site dedicated to environmental/green issues, and this Mozilla announcement has nothing to do with that, except that they now use the word organic.

Sorry Mozilla, a vote down on this marketing strategy from me.