Java Analysis Studio

1
Java Analysis Studio

• Tony Johnson
• tony_johnson_at_slac.stanford.edu
• Stanford Linear Accelerator Center
• CHEP 97 - April 1997

2
Contents

• Java Analysis Studio - Goals
• Intro to Java
• Why Java for Distributed Physics Analysis?
• Implementation
• Why Java - Reprise
• Demo
• Current Status Plans Call for Input

3
Java Analysis Studio - Goals

• Project based
• Data, histograms, fits, programs all stored in
  project.
• Can close project and return to exact same place
  tomorrow
• Experiment/Data format independent
• Distributed data analysis
• Integrated with other applications

• Analysis code written in Java
• Java excellent language for RAD physics
  analysis
• Build on SLD experience with IDA
• Provide a rich set of OO analysis tools
• Histograms, plots, fits etc.
• Portable
• compiled on desktop
• executed on dataserver
• Supports Remote debugging
• Efficient (JIT)
• Widespread industry support

4
What is Java?

• History
• Originally designed (1991) as a small language
  for consumer electronics (cable boxes, toasters
  etc.)
• Eventually someone wrote HotJava Browser, which
  could run Java Applets
• Adopted by Netscape, Microsoft, Sun etc. as Web
  Programming Language.
• More than just a Web Tool
• Java is a fully functional, platform independent,
  programming language
• Powerful set of machine independent libraries,
  including windowing library.

5
Totally Buzzword Compliant

• Simple
• well, simpler than C
• Object Orientated
• more so than C
• Distributed
• Built in support for Internet protocols, URLs,
  HTTP, Remote Method Invocation, DB access etc.
• Robust
• Impossible to create memory leaks, go beyond
  the end of an array, corrupt stack or code
• Secure
• Bytecode verifier, padded cell

• Architecture Neural, Portable
• Runs on PC, MAC, Unix, VMS
• Interpreted
• Compiler converts code into machine independent
  bytecodes
• High Performance
• With JIT compiler still 2-3 times slower than
  native C, but...
• Multithreaded
• Language has direct support for multithreading
  (cf. subprocesses)
• Dynamic
• Libraries can change without recompiling programs
  that use them

6
Wheres the Meat?

• JDK 1.1 adds
• Object reflection
• Object serialization
• Remote Method Invocation
• CORBA support
• JDBC interface
• Standardized native interface
• 2d3d API on the way

• Extensive built in library (including Math)
• Can read in unknown data and analyze it
• Can really store objects in databases (not just
  object data)
• Client Server applications straightforward

7
Why Learn Java?

• Stepping stone to C
• Cleaner syntax
• not backward compatible with C
• More concerned with programmer efficiency than
  run-time efficiency
• Far less gotchas
• Especially memory management
• Full object orientated language
• Syntax very similar to C
• Good language for writing medium sized portable
  applications, including GUI applications
• Good candidate to replace KUIP/Comis/IDA/etc as
  physics analysis language
• Web Applets
• Hopefully useful ones
• Database access
• Data presentation

8
Java for Physics Analysis
9
Java for Physics Analysis - 2
10
Implementation- Model
TCP/IP Network
Data Analysis Engine
GUI
Padded Cell
Experiment Extensions (Event Display)

• Data
• Zebra
• Jazelle
• Paw
• Root
• Objectivity

Experiment Interface
C Code
11
Implementation - Details

• Original plan was to write C/MFC/COM
  application for Windows
• Later converted to 100 pure Java
• Works everywhere
• Fast (enough)
• Rapid deployment of commercial tools
• IDEs
• Extensions
• Components

• Use commercial components where ever possible
• Dont want to write our own plotting package
• Olectra Chart
• C activeX control
• Jchart
• Java Bean
• Wrap in interface layer to make it possible to
  change later.

12
C/Java Comparison
13
Implementation - Local Objects
Histogram
Plot
Analysis Studio Histogram
Analysis Studio Plot
Data request
Data Update Notifications
14
Implementation - Remote Objects
Histogram
Plot
Remote Adaptors Deal with data batching, Caching,
network exceptions
Analysis Studio Histogram
Analysis Studio Plot
15
Lessons Learned - 1

• Microsoft programmers drink too much Jolt Cola
• Win32/MFC/COM/ActiveX system was not designed to
  be easy to learn
• WHILE (ltusers having problems learning systemgt)
• ltwrite more documentationgt
• Microsoft is changing/extending things faster
  than the speed of learning
• Once things fall into place it is possible to
  exploit Microsoft environment to rapidly build
  applications

16
Lessons Learned - 2

• Commercial software components can be very cost
  effective
• Commodity software has large market, therefore
  cheap
• Commercial plot package with more options than
  HBOOK cost 249, with no run time license.
• Can wrap commercial components with HEP component
  layer

17
Demo!!!
18
Current Status Plans

• Web site
• http//www-sldnt.slac.stanford.edu/JAS
• Version 0.1 available for download end of April
• clientserver
• masochists only!
• Join discussion group
• We want your input
• Ideas, Opinions and/or Code!