Brian Murphy, Senior Staff Engineer was a fantastic speaker and got more information across in his 1 hr timeframe than any other presentation so far. He has worked on the Jini project since it's inception. He started off with an overview of what Jini is. He also stressed that local objects are different than remote and should be treated accordingly. The decision to make a given object local or remote should be determined early in the development process. All and all, Jini is something that I'm very interested in and I need to do a sample app to get a grasp on how I could use it.

What is Jini Technology

• Service based architecture for building networked systems that can adapt to change
• set of specifications
• a programming model
• Contributed implementations(Jini Technology Starter Kit)
• A Community

Summary
Jini technology is a programming model
Jini technology places the agreement in the interface, not the protocol
Jini technology security model extends the java security model, it doesn't reinvent the wheel
Think of development and deployment as separate activities
develop with deployment in mind
always 'security ready'

Links
Jini.org
Presentation

This was an interesting session. Many details about how to increase performance and reduce the memory footprint were discussed. An example would be a single computer with multiple virtual machine's each running their own application. Each VM loading java.lang.String is wasteful and could be made better if multiple applications could run inside an MVM(Multitasking Virtual Machine). This concept is very similar to Operating System processes and threads. i.e. Creating a new process is an expensive, costly unit of work. Creating a thread within a process is relatively inexpensive unit of work. So the parallel is that a single MVM running multiple apps is more efficient like a multi-threaded operating system process. The downside to this is that if one app were to puke(warning: graphic technical term), it would take down the other apps with it. The presenter discounted this argument based on all the VM enhancements that are occuring. He did say that collocation could be achieved by running multiple MVM's on a single machine. This is a special case though.

Responses[4]

Posted by Mike Shoemaker on June 29, 2004 3:59:16 PM CDT #

This is the first session that I left early. I really didn't learn much more from this session than a handout from marketing could have conveyed. In a nutshell, the high points were the following.

• Apple Ships multiple VM's on every machine
• Apple is Open and Standards based like Java
• Ant, Tomcat, Jboss, and Eclipse all run on OS X
• Apple supports the JCP

Last night a large group of geeks got together for a beer and some socializing at the Thirsty Bear. I think the event was set up by Simon Phipps, but many java bloggers attended. Heck, even Jonathan Schwartz, President and Chief Operating Officer of Sun Microsystem's showed up. Apparently, he has a blog as well.

As a side note, I would like to thank the guys from Atlassian for the java.blogs tshirt. The tshirt says, "More People read this tshirt than my blog" or something to that affect. Tshirts are top notch and have high geek appeal.

I got to meet Simon Brown and Sam Dalton while at the meetup. Although, I didn't get to buy Simon the beer I promised him. So Simon, if we meet up again, first beer is on me.

At the end of the night, Andrew and I spoke with Erik Hatcher for sometime about Struts and it's problems. Erik strongly suggests Tapestry so we may have to give it a test drive soon. I saw Erik's talk on Tapestry at the 2004 NoFluffJustStuff Gateway Java Symposium and I have to admin I was impressed. The question is, is it worth learning another framework that most people are comfortable. Regardless, a test drive is not out of the questions. If nothing else, it's a learning experience.

Concurrency Utilities in JDK Software Version 1.5: Multithreading Made Simpler

David Holmes
Brian Goetz

This was a very informative session about changes coming forth to the java.util.concurrent package. Having written very few multi-threaded applications in Java, some of this presentation went over my head. The overall theme was that things that used to be impossible are now possible and things that used to be hard are now managable. The API looked pretty clean and backward compatibility was a priority. Listed below are some bullet points of the presentation.

Why JSR 166
  Primitives like wait(), notify(), and synchronized are primitive
  Hard to use correctly
  easy to use incorrectly
  specified at too low a level for most apps
  can lead to poor performance if used incorrectly
  too much wheel reinventing

Goals for JSR 166
  Do for concurrency what the collections framework did for data structures

The Improvements to Tiger should:
  Make some problems trivial to solve by everyone
  Make some problems easier to solve by concurrent programmers
  Make some problems possible to solve by concurrency experts

Based mainly on package EDU.oswego.cs.dl.util.concurrent from http://gee.cs.oswego.edu by Doug Lea
  APIs refactored based on 4+ years of usage
  APIs enhanced to use generics

Java Platform performance

Tim Cramer, David Dagastine, Ben Kim
Sun Microsystems

Focus: Understand how to measure performance.
Should performance be added as a step to the development process?

Why taking the average when using benchmarks doesn't work
2 runs score 24 and 26 vs. score of 1 and 49.
Both average 25

Beware Microbenchmarks!

Student's T-Test
Determine confidence between 2 data sets
Want 95% or higher confidence level, p-value 0.05

Modern Java Virtual Machine(JVM) Software Microbenchmark Negating Characteristics
Warmup period for Dynamic compilation
on-stack replacement
separate compile thread
disk cache
  On by default on on-solaris x86 OS-based systems
  Off by default on Solaris x86 OS-based systems

Statistical Gathering
  Monomorphic call transformation
  branch targets
  execution frequency

Background Compilation
  -Xbatch

Compiler Optimizations
  Dead code removal
  Inlining

Tips and Tricks
JVM Software Performance Tuning, pre 1.5
  Java hotspot VM is highly tunable

Select Server compiler with -server flag
Correctly size the overall heap
set min/max of heap to same value to minimize resizing
  +AggressiveHeap flag
    size of initial heap based on avail memory MIN(1/2 RAM, RAM-160M)
    flag can change at anytime!

Monitor JVM software using JVMstat tools

New garbage collectors
  Default
  Incremental
  Throughput

New Features of JDK 1.5
Smart Tuning
  Provide good out of the box performance without hand tuning
  examine host machine and configure hotspot appropriately
  dynamically adjust java hotspot VM software at runtime
  adaptive heap sizing policy during life of application.

client performance
  Class data sharing
    faster classload = faster startup time
    shared class archive, reduce footprint
    JFC/Swing and Java 2D API improvements

Overall
  know how to write a microbenchmark before doing so
  upgrade to jdk 1.5
  understand OS and hardware

http://java.sun.com/docs/performance

Wall Street, Grid Computing and Jini Network Technology

Van Simmons
Director, Fixed Income Development
Invesco http://www.invesco.com

Observations
Software architecture is THE bottleneck
Too many systems rely on Moore's law to solve scaling and performance problems
Use of Excel considered harmful(except at presentation layer)

What Does Grid Computing Mean?
It describes a state of being, not an activity. Imparting meaning to the phrase requires a clear specification of the processes involved.
Service Oriented Architecture(SOA) emerges from the fog of jargon

The backbone of continuously available services that emerges is "THE GRID"

Our Jini Technology Implementation
Master /Worker pattern
Bootstrapping
GridApps
Worklets and a Worklet Container
Single sign-on
GridManager
Administrator

Master putting together set of tasks to be done, puts it in the javaspace, worker then calculates the answer and puts it back in the javaspace.

Tuple space-based approach known to jini Koolaid drinkers as standard pattern
First thing in all the books seems quite intuitive pretty much where we started
Things that get left out of the books
Security
Management/monitoring
Reliability
Deployment/multi-purposing of the grid

Deutsch's 8 Fallacies
1. The network is reliable
2. Latency is zero
3. Bandwidth is infinite
4. The network is secure
5. Topology doesn't change
6. There is one administrator
7. Transport cost is zero
8. The network is homogeneous

The Future: Federation No single points of failure

Java One Keynote

Im sitting here attempting to blog about the presentation, but the WiFi access is pretty bad. Im dropping on and off the network like a blind bird on a wire. Java in Action is being played as the presentation is beginning. It is an overview of all the various niche markets Java is being used in. Embedded systems are a accentuated.

Gosling is actually online here at the Keynote, I can see him via Rendevous on iChat. How cool is that!

The JavaOne Keynote is being presented by
Jonathan Schwartz, President and Chief Operating Officer of Sun Microsystems.

Topic: Everything and everyone connected to the network.
Global Vision: Network is growing.

• 1 Billion computers attached to the network
• Appliances/Toys 11 Million
• Handhelds 2600 Million
• Entertainment 1300 Million
• Industrial/Automotive 400 Million

RFID are being used everywhere. From Pfizer tracking drugs, to Gillet tracking razors. Use java card to access the building and network. Java is everwhere TODAY.

350 Million Java Handsets in the marketplace. Driven by JavaCard. 600 million have been shipped to date. The desktop is coming back due to Java. 650 Million PC's have shipped with the java runtime.

100 million jdk downloads to date.

1.5 million downloads of j2ee 1.4

2.2 Billion in java app servers, 110B in related IT spending.

4 Million Java Developers, last year was 3 million. Stretch goal is 10 Million.

Java economies are thriving. More and more devices are getting java. Embedded systems are becoming more and more everyday.

MedicTouch. Wristband that measures telimetry off your body. Uses bluetooth to display readout on cell phone. Showing pulse on telephone. Give this to someone and data mine medical data. Java is used to monitor human beings. Company was started by a bunch of doctors so doctors could get statistics without the patient coming into the hospital.

Clients are back. Market was pretty slow and really owned by 1 company.

Qnext, truly connected. Instant messaging software. video and voice messaging. Basically a rip off of ichat. Not overly impressed as I have had this technology on my Powerbook for sometime now.

Tiger is here.

Automobile industry is next to be revolutionized with Java. Automobiles are going to talk to the network. All the seat back LCD's are going to connect to the network in some way.
Dr Roland Busch CEO Siemens VDO Automotive AG. Brought in BMW Z4, Java based entertainment system. Gets driving directions via the Navigation System.

John Loiacono Executive Vice President, Sun Software, Sun Microsystems.
The Client is back. Says, he is hearing Java needs to be easier for the developers. Sun Developer Tool Portfolio. Bringing more developers to java. Visual, simple, fast and familiar. Sun Java Studio Creator, visual development tool. RAD, Complete solution, 100% Java, built on Netbeans IDE. Sun Creator is releasing today. The Creator demo looks a lot like drag and drop visual basic applications. Except Creator is a GUI builder for Web Applications. Pages are wired together through drag and drop.

Sun Java Studio Creator, 40, 000 Users, 1000 Companies. Creator is priced effectivly at Free. You can subscribe to the Sun Developer Netork. Forum's, chat, and example apps. Special for Today. $49.95 for for SDN and throwing in a book Java Studio Creator Field Guide.

Project Kitty Hawk - Service Oriented Architecture.
What Developers Need? Tools, code samples, runtimes, and tutorials. How much would you pay for that? Throw in a wicked fast computer. Should we put this package on ebay to determine what people will pay for such a package.

Back to Jonathan.
Theres a new market emerging. How to push the free software, fast hardware, with updates out to the consumers. Java.com, Java is all about community.
Project Looking Glass, should we open source it. Open source Java 3D is now available at java.net. Demo of project looking glass was lots of hype wioth the ability to flip windows upside down, on their sides, or turning them around. How useful is this. In my opinnion, it is vast overkill and that Apple's Expose Feature is more productive.

The bottom line is that Java = Opportunity now and in the future.