Java Emerging Technology overviegiven to Solnet team after attending the event.

1. Solnet Solutions Ltd
JET (Java Emerging Technology)
Conference – September 2008

2. JET (Java Emerging Technology)
Conference
 http://java.meetup.com/162
 Conference Details
 Organised by the Auckland Java Group
 http://jet.javacom.co.nz
 Outline of the sessions attended
 Java 7, EasyB, Scala, Groovy, Grails, J2ME and
Android
 Future Presentations on sessions attended…

3. Java 7
 What is likely to be in included in Java 7?
 What impacts us? Do we care?
 JSR 294 – Super Packages
 JSR 297 – Java Module System (JAMS)
 JSR 310 – Date and Time
 JSR 210 – New NIO
 JSR 295 – Beans Binding
 JSR 303 – Bean Validation
 JSR 292 – Invoke Dynamic

4. Java 7
 Other includes…
 JSR 166 – Concurrency
 JSR 296 – Swing
 JSR 225 – XQuery API
 JSR 255 – JMX 2.0
 JSR 262 – Web Services Connector for JMX
 …but not likely to be included…

5. Java 7
 Not likely to be included in Java 7
 Closures
 JavaDoc Update
 Refined Generics
 Property Support
 List of all JSR’s - http://jcp.org/en/jsr/all

6. EasyB
 BDD (Behaviour Driven Development)
 Specifications based DSL written in Groovy
 ‘Test’ replaced with ‘Should’
 Uses an easy-to-understand structure
– Given [a context]…
– When [something happens]…
– Then [something else happens]…

7. EasyB
 EasyB example code:
scenario “Make initial deposit onto a new account”
given “a new account”, {
account = new Account()
}
when “an initial deposit is made”, {
initialAmount = 100
account.makeDeposit(initialAmount)
}
then “the balance should be equal to the amount deposited”, {
account.balance.shouldBe initialAmount
}
 http://easyb.org – EasyB website
 http://weblogs.java.net/blog/johnsmart/archive/2008/09/a
- John Smart’s Presentation
 Java Power Tools – O’Reilly

8. Scala
 Object Orientated Functional Language
 Runs on the JVM
 Release candidate status (2.7.2 RC2 – 19/09)
 Types and behaviours are described by classes
and traits
 Has implicit type inference, closures and powerful
pattern matching
 …lets take a look at some code…

9. Scala
 Love Game – Java Code
// Creates 2 character arrays that will be compared
char bothNamesArray[] = “roger federer maria sharapova”.toCharArray();
char compWordArray[] = “loves”.toCharArray();
// Creates an Integer array for storing count results
Integer tallyArray[] = new Integer[compWord.length()];
int tallyArrayPointer = 0;
int matchCounter = 0;
/*
* Counts the number of times each character in compWordArray also
* appears in bothNamesArray
*/
While (tallyArrayPointer < compWord.length()) {
for (int i = 0; i < bothNames.length(); i++) {
...
 ..enough of that…let’s do this with Scala…

10. Scala
 Love Game – Scala Code
val names = “roger federer maria sharapova”
val initialList = “loves”.toList map( x => names.toList count(x == _))
def loveReduce(numbers:List[Int]):Int = numbers match {
case head::Nil => head * 2
case _ => loveReduce(numbers zip(numbers tail) map { case (a,b) => a + b})
}
// Displays the compatability percentage
println(“Compatibility = “ + loveReduce(initialList) + “ %”)
 …much better?
 Notes about the example:
 Syntax – no semi-colons, optional parentheses
 Pattern matching, List operations

11. Scala
 Scala Resources
 http://www.scala-lang.org
 http://stubbisms.wordpress.com/2008/02/22/my-foray-in
- Love Game Example
 http://www.codecommit.com/blog/scala/roundup-scala-f
 Series on IBM Developerworks – Scala for the
busy Java Developers

12. Groovy
 Dynamic Language
 Runs in the JVM
 Shell Interpreter
 Supports DSL (EasyB)
 Seamlessly integrates with all existing Java objects
and libraries
 Useful for scripting builds (integration with Maven
and Ant)
 Useful for quick prototypes

13. Groovy
 So why learn Groovy….
 JDBC Example – Java Code
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
public class JDBCExample {
public static void main(String[] args) {
Connection con = null;
...
try {
// Connection code`
} catch (SQLException e) {
e.printStackTrace();
} catch (ClassNotFoundException e) {
e.printStackTrace();
} finally {
...
 …enough..my fingers are hurting..let’s get Groovy…

14. Groovy
 JDBC Example – Groovy Code
import groovy.sql.Sql
class GroovySqlExample {
static void main(args) {
sql = Sql.newInstance(“jdbc:mysql://localhost:3306/words”, “words”,
“words”, “org.gjt.mm.mysql.Driver”)
sql.eachRow(“select * from word”) { row ->
println row.word_id + “ “ + row.spelling + “ “ + row.part_of_speech
}
}
}
 Notes on the example code
 eachRow method – iterator of the passed in query
 Closure used for each result row
 Groovlet and Groovy Templates

15. Groovy
 Want to learn more about Groovy?
 http://groovy.codehaus.org
 Practically Groovy series on IBM Developerworks
(some of the examples in earlier parts are
outdated)
 Slides from the presentation at JET conference will
be available online soon

16. Grails
 Web application framework leveraging Groovy
 Aims to simplify development
 “coding by convention” – file system, file names
and such carry meaning (replace XML
configuration files)
 Leverages Hibernate and Spring
 Quick and simple to set up and deploy an
application
 Excellent documentation compared to Groovy
 http://grails.org

17. J2ME
 Latest developments in J2ME development
 UI Developments
 LWUIT (LightWeight User Interface Toolkit)
 - Swing like capabilities
 - IDE Demo had screen refresh issues
 Flex Mobile
 Technical Development
 Application Signing (allows access to comms and database)
 Difficulties with BlackBerry Development

18. Android
 Google Android mobile platform using the Java
programming language
 Access to core mobile device functionality
 Easily embed the web with WebView
 SDK – Eclipse IDE (Simulator)
 Demo application – Issues with screen refresh as
per J2ME LWUIT
 Android Developer challenge
 http://code.google.com/android