Advanced Analysis Environments

1
Advanced Analysis Environments

• What is the role of Java in physics analysis?
• Will programming languages at all be relevant?
• Can commercial products help meet our needs in
  this area?
• What is the role of modularity and abstract
  interfaces?
• Do we want an all encompassing framework or a
  collection of configurable tools?

2
What is the role of Java in physics analysis?

• Java is a great language for analysis (among many
  other things)
• Clean, modern, OO language, relatively simple
• Platform independent
• Mainstream language
• Enormous set of standard and third party
  libraries
• Distributed computing, networking, CORBA, RMI
• Graphics, 2D and 3D, GUIs
• Collections, Hash tables, Maps, Vectors, Binary
  Trees, Sorting
• IO, Compression, Encryption
• Large research teams working on development and
  performance

3
Java for Data Analysis

• Maximizes programmer/physicist efficiency
• Memory allocation taken care of for you
• No dangling pointers
• No core dumps
• No memory leaks (unless you try hard)
• No need to reinvent the wheel
• Very fast compile/(dynamic) load/debug cycle
• Spend time designing analysis program solving
  physics problems, not working around language
  problems

4
Java for Data Analysis

• Previous generation of experiments used Fortran
  Data Management System ( Jazelle, Zebra, BOS)
• Solves Three Problems
• Ability to Represent Complex Data Structures
• Persistence (i.e. read in and write out complex
  structures)
• Run time access to named data in structures (for
  analysis)

• Now time has marched on and modern experiments
  use C
• Represent Complex Data
• Persistence
• Run time access to data
• Still need to build (or buy and deploy) data
  management system (e.g. Root, Objectivity)
• Java
• Represent Complex Data
• Persistence (serialization)
• Run time access to data (reflection)
• support built-in to language

5
Isnt Java too damn slow?

• No!
• Huge advances have been made in last 4 years
• Dynamic code optimization
• Optimizes code while it is running
• Java now gives average of 60 of C performance
• Java performance continues to improve
• Static optimization (C) is mature no
  improvement expected

6
Examples of Java in Data Analysis

• WIRED Experiment independent event display
• JAS Java Analysis Studio
• Linear Collider Detector
• Entire reconstruction/analysis framework is in
  Java
• Modular components are also reusable and are
  being moved to FreeHEP library
• FreeHEP library
• CLHep for Java (see talk ISAT201 tomorrow)
• Code from WIRED, JAS, Atlas, Babar, LCD
• In future JASWIRED will both become plugins for
  HEP Studio, part of FreeHEP Java library

7
JAS WIRED LCD
8
Example Analysis
9
Java and the GRID

• Java has built-in support for distributed
  computing and Networking
• Rather than move all the data to the user,
  transparently move code to data
• Download JAVA analysis agents into remote
  server
• flexible built-in padded cell protects server
  from analysis modules
• Give user impression code is running locally

10
Will programming languages at all be relevant?

• Not once we can say Computer please analyze
  the LEP data and compute the mass of the Higgs
• Until then - Yes
• GUI tools are important too but
• The complexity of physics analysis algorithms are
  best expressed in terms of programs
• Graphical representation of analysis is simply
  inadequate and inefficient

11
Can commercial products help meet our needs in
this area?

• Yes we will not use a single tool, we will use
  many tools which can inter-operate
• Some commercial
• Some HENP specific
• Home grown tools will always have a place
• Our statistical usage of data and volume of data
  still tends to make mainstream commercial tools
  difficult to use

12
What is the role of modularity and abstract
interfaces?

• Fundamental to good OO design
• Separate interface keyword in Java language
  highlights importance of abstract interfaces
• Separation of interface and implementation
• Allows isolation of components within tools
• Allows interoperability between tools
• Allows user extensibility
• Allows substitution or co-existence of
  components/tools
• Prevents us getting stuck in a rut
• PAW/CERNLIB

13
JAS Modules
14

• AIDA Abstract Interface for Data Analysis
• LHC/Lizard, JAS, Open Scientist, COLT
• Interoperability/data exchange
• Familiarity to users
• Geant4 AIDA test bed

A I D A
C Program
C AIDA Implementation
A I D A
A I D A
Java AIDA Implementation
C Program
C -gt Java
A I D A
Java Program
Java AIDA Implementation
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Do we want an all encompassing framework or a
collection of configurable tools?

• Why not both?
• JAS/FreeHEP provides set of highly modular tools
• A framework which brings them all together
• Framework is extensible and customizable
• Users can pick and choose

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Links

• JAS http//jas.freehep.org
• WIRED http//wired.cern.ch
• FreeHEP Java Library http//java.freehep.org