Download Java and Java EE Future

Java and Java EE
Future
Tao Li
Technology Evangelist
[email protected]
Sun Microsystems
Agenda
•Language and platform Wars
•Java Runtime Improvement
•Java EE Improvement
JavaScript
Java
Python
Language Wars
Ruby
Perl
Micro Case Study:
s1 is a string variable containing “1”
n2 is an integer variable containing 2
To do: compute a string named s12 with
the values concatenated, and an integer
named n3 with the values added.
D12.java
class D12
{
public static void main(String args[])
{
String s1 = "1";
int n2 = 2;
String s12 = s1 + Integer.toString(n2);
int n3 = Integer.parseInt(s1) + n2;
System.out.println("s12: " + s12 + ", n3: " + n3);
}
}
D12.pl
$s1 = '1';
$n2 = 2;
$s12 = $s1 . $n2;
$n3 = $s1 + $n2;
print "s12: $s12, n3: $n3\n";
D12.py
s1 = '1'
n2 = 2
s12 = s1 + str(n2)
n3 = int(s1) + n2
print "s12: " + s12 + ", n3:", n3
D12.rb
s1 = "1"
n2 = 2
s12 = s1 + n2.to_s
n3 = s1.to_i + n2
puts "s12: " + s12 + ", n3: " + n3.to_s
Comparison
Java
Perl
Python
Ruby
Lines
11
5
5
5
Characters
240
85
88
93
What’s a Modern Language?
•It’s Object-Oriented.
•You don’t do memory management.
•Runs on some sort of VM.
Dynamic Language advantage
•Each statement does more work.
•You don’t have to declare variables.
•Variables can hold different types.
•Precompilation is not required.
•So, the same amount of work with less code!
Dynamic-Language Scorecard
•JavaScript: hot because of AJAX
•Perl: currently too ugly, blocked waiting for Perl6
•Python: large community, lots of production apps
•Ruby: great language, recently got a community
because of Rails
Why Not Dynamic Languages?
1.No static typing, so it’s unsafe and buggy, just like
bad old C code.
2.It doesn’t run on the JVM, so it’s hard to integrate
with existing apps.
Static Typing is Overrated!
Static typing prevents certain failures
but, in so doing, it prevents certain
types of successes. - Sean McGrath
Static Typing is Overrated!
Test-Driven Development produces the
same level of safety as compile-time
static type checking. - Bruce Eckel, Paul
Graham, Robert C. Martin, many others...
Why Not Dynamic Languages?
1.No static typing, so it’s unsafe and buggy, just like
bad old C code.
2.It doesn’t run on the JVM, so it’s so hard to
integrate with existing apps.
Big problem!
Java’s Advantages
1.Static typing gives the IDE a lot of help, so that
even if you have to write more code, it might not
take any longer.
2.Compile-time type knowledge allows faster
dispatching than “duck typing”.
3.More memory-efficient.
4.Real threads.
Should you choose Java Programming language?
There is no best choice, but most appropriate!
Parrot
Java
Platform Wars
.NET
The Java Platform (Today)
JVM
Java
Language
APIs
A Future Java Platform
Java
Ruby
JVM
JavaScript
Python
etc...
APIs
Example: Servlets With Jython
JSR 223
•No deployment
•Full access to Java APIs
•Full access to Python APIs
•Interactive testing
•Fast development
Why the Java Platform Can Win
•Installed base
•Performance
•Multithreading
•Libraries
Java Runtime
Improvement
What does the JRE look like now?
25
But...
26
Java SE 6 Update N
• Java 6 update, targets easier, better and faster end-user distribution
> First half of 2008
•
•
•
•
•
Improved installer
Java Technology Deployment Kit
Highly modularized
Quick start service
Better default Look & Feel
27
Modularization
• Minimum initial size – about 2M
> basic functions needed by every program
• Download the rest of JRE in parallel
• Missing components will be downloaded on demand
28
Estimated Runtime Sizes
29
Java Technology Deployment Toolkit
Technologies for detecting and deploying Java
• JavaScript APIs
> Hosted by Sun @ http://java.com/js/deployJava.js
• Browser Plugins
• Stand alone executable
> getjava.exe
30
Java Quick Start Service
• Background process which periodically reads from JRE files, keeps them in
the disk cache
• With files in disk cache, it becomes Warm Start
• Doesn't really consume memory: it is in the disk cache
• Automatically shutdown on Memory Constrained systems
31
Java EE Improvement
History of Java Enterprise Platform
Ease of
Development
Java EE5
Web
Services
Enterprise
Java
Platform
J2EE 1.2
JPE
Project
May 1998
Robustness
J2EE 1.3
EJB 2.0,
Connector
Architecture
J2EE 1.4
Web Services,
Management,
Deployment,
Async.
Connector
Annotations,
EJB 3.0,
Persistance
API,
JSF,
Renewed Web
Services
Servlet,
JSP, EJB,
JMS, JTA,
JNDI,
RMI/IIOP
Dec 1999
Sept. 2001
Nov. 2003
May 2006
Java EE 5
• Ease of development
> POJO Programming
> Annotation
> Resource Injection
• JPA
> New persistence model replaced Entity Bean
• JSF
> New component based MVC framework
• JAX-WS and JAXB 2.0
Java EE 6
• Rightsizing
> Profiles: The Web Profile, a subset of the platform
focussed on Web Applications
• Further ease of development
> Java EE 5 - EJB simplifications
> Java EE 6 Web Tier and packaging simplifications
• Extensibility
> Allowing for Open Source Frameworks to be
plugged in via a standard mechanism
“Java EE 6 will be the most important release of the
platform since it was released 10 years ago” -- Rod
Johnson, Inventor of Spring
Java and Java EE
Future
Tao Li
Technology Evangelist
[email protected]
Sun Microsystems