Introduction to Java Development with IDS

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1 Introduction to Java Development with IDS Jean Georges Perrin IIUG GreenIvory.com Tuesday, October 3 rd :00 10:00. JGP.net Platform: IDS, Java 1

2 Agenda Who am I? Architecture Requirements Your very first cup of Java JDBC Your first application using the Command Prompt Your first application using Eclipse Your first application using a framework 2

3 Agenda Who am I? Architecture Requirements Your very first cup of Java JDBC Your first application using the Command Prompt Your first application using Eclipse Your first application using a framework 3

4 Who am I? My Unix box usually answers 4

5 Who am I (outside of a Unix box)? Jean Georges Perrin Development tools (xgl, Java EE, PHP) Works with Informix products since 97 IIUG board member since 02 Lives in Strasbourg, France 5

6 A little more Application developer, started with Visual Basic, in the early 90s In the web since 1994 Move to 4GL in 1997 Goals: Webizing all things I touched (business apps, catalogs and i-4gl ) Find the ease of use of Visual Basic 6

7 And you Who knows 4GL? Who knows Java? Who thinks Java is difficult? Who knows.net? 7

8 Agenda Who am I? Architecture Requirements Your very first cup of Java JDBC Your first application using the Command Prompt Your first application using Eclipse Your first application using a framework 8

9 Architecture Application JDBC Driver Data 9

10 Agenda Who am I? Architecture Requirements Your very first cup of Java JDBC Your first application using the Command Prompt Your first application using Eclipse Your first application using a framework 10

11 Requirements #1 - IDS (from v7.x, but also works on OnLine and SE) Where: #2 - Java (Java SDK v5.x) Where: #3 - JDBC driver (IBM Informix JDBC 3.0) Where: #4 - Option: Eclipse (v3.2.1) Where: 11

12 Agenda Who am I? Architecture Requirements Your very first cup of Java JDBC Your first application using the Command Prompt Your first application using Eclipse Your first application using a framework 12

13 Your very first cup of Java fglpc Hello, world in Java Use of javac Use of java fglgo Source code is self organizing in packages Code snippet: Modules are organized in classes main { } is MAIN END MAIN package org.iiug.test; public class HelloWorld { } public static void main(string[] args) { System.out.println("Hello, world..."); } 13 Hello, world is always the same, in any language

14 Java Pros & Cons Object Oriented (OO) development Event driven programming model User Interface (UI) & Business Logic (BL) tightly linked Open architecture, open standards General purpose development language Industry standard Looks like hype to developers 14

15 4GL Pros & Cons Procedural development Controlled events UI and BL somehow separated (.per &.4gl) Proprietary solution Business apps development language Not a standard in industry Hard to attract new developers 15

16 Agenda Who am I? Architecture Requirements Your very first cup of Java JDBC Your first application using the Command Prompt Your first application using Eclipse Your first application using a framework 16

17 JDBC Types of driver (annoying theory) Standard way of talking to a database (forget about SQL/J) Use a URL, for IBM Informix: jdbc:informix-sqli://popeye:1526/stores_demo: informixserver=ol_popeye; user=informix; password=informix 17

18 Agenda Who am I? Architecture Requirements Your very first cup of Java JDBC Your first application using the Command Prompt Your first application using Eclipse Your first application using a framework 18

19 Your first application using the Command Prompt Understand the role of the CLASSPATH Full source code (copy / paste): import java.sql.*; public class MyFirstJDBCConnection { public static void main(string[] args) { // Define my local variables Connection myconnection; Statement mystatement; ResultSet myresultset; // Loading driver try { System.out.println(">> Loading the driver"); Class.forName("com.informix.jdbc.IfxDriver"); } // end try catch (ClassNotFoundException e) { System.out.println("ERROR: Failed to load IBM Informix JDBC driver."); return; } // end catch 19

20 Your first application (2) try { // Connection to database System.out.println(">> Connecting to the database"); myconnection = DriverManager.getConnection ("jdbc:informix-sqli://popeye:1526/stores_demo: informixserver=ol_popeye;user=informix;password=informix", "", ""); // Statement creation System.out.println(">> Creating the statement"); mystatement = myconnection.createstatement(); // Resultset creation & execution System.out.println(">> Executing the query"); myresultset = mystatement.executequery ("SELECT fname, lname, customer_num FROM customer ORDER BY lname"); // Outputting the result System.out.println(">> Step 4 - Dumping data"); while (myresultset.next()) { System.out.println ( myresultset.getstring("fname") + myresultset.getstring("lname") + " (" + myresultset.getstring("customer_num") + ")"); } 20

21 Your first application (3) // Cleaning System.out.println(">> Cleaning"); myresultset.close(); mystatement.close(); myconnection.close(); } // end try catch (SQLException e) { System.out.println("ERROR: SQL exception: " + e.getmessage()); e.printstacktrace(); return; } // end catch } // end main } // end class 21

22 Declaring objects to use // Define my local variables Connection myconnection; Statement mystatement; ResultSet myresultset; Code snippet: Connection = DATABASE The Connection is the real connection Statement = STATEMENT to the database, it is (re)created each time. Except when using connection pooling. The Statement is the real orders or queries to the database. The ResultSet contains a link ResultSet to the = ARRAY data. OF RECORD / CURSOR 22

23 Loading the driver Code snippet: // Loading driver try { System.out.println(">> Loading the driver"); Class.forName("com.informix.jdbc.IfxDriver"); } // end try catch (ClassNotFoundException e) { System.out.println("ERROR: Failed to load IBM Informix JDBC driver."); return; } // end catch Drivers are uniquely named, for IBM Informix: com.informix.jdbc.ifxdriver 23

24 Connecting to the database Code snippet: // Connection to database System.out.println(">> Connecting to the database"); myconnection = DriverManager.getConnection ("jdbc:informix-sqli://popeye:1526/stores_demo: informixserver=ol_popeye;user=informix;password=informix", "", ""); 24

25 Statement & Execution Code snippet: // Statement creation System.out.println(">> Creating the statement"); mystatement = myconnection.createstatement(); // Resultset creation & execution System.out.println(">> Executing the query"); myresultset = mystatement.executequery ("SELECT fname, lname, customer_num FROM customer ORDER BY lname"); 25

26 Looping around Code snippet: // Outputting the result System.out.println(">> Step 4 - Dumping data"); while (myresultset.next()) { System.out.println ( myresultset.getstring("fname") + myresultset.getstring("lname") + " (" + myresultset.getstring("customer_num") + ")"); } 26

27 Cleaning Code snippet: // Cleaning System.out.println(">> Cleaning"); myresultset.close(); mystatement.close(); myconnection.close(); } // end try catch (SQLException e) { System.out.println("ERROR: SQL exception: " + e.getmessage()); e.printstacktrace(); return; } // end catch } // end main } // end class Not only cleaning Exception Handling! 27

28 Agenda Who am I? Architecture Requirements Your very first cup of Java JDBC Your first application using the Command Prompt Your first application using Eclipse Your first application using a framework 28

29 Your first application using Eclipse Create a project Add the library Create the class Run it 29

30 Agenda Who am I? Architecture Requirements Your very first cup of Java JDBC Your first application using the Command Prompt Your first application using Eclipse Your first application using a framework 30

31 Your first application using a framework Goals of a framework Ease of use Small learning curve Database connectivity Business logic 31

32 BlueGazelle Open Source framework Soon to be downloadable from 32

33 BlueGazelle Source Code Code snippet: Database mydatabase = null; Record myrecord = null; Record myrow = null; int count = 0; int i = 0; try { mydatabase = Databases.connect("stores_demo"); myrecord = mydatabase.createrecordfromselect("select fname, lname, customer_num FROM customer ORDER BY lname"); count = myrecord.getcount(); for (i = 0; i < count; i++) { myrow = myrecord.getrecordat(i); System.out.println(myRow.getString("fname") + myrow.getstring("lname") + " (" + myrow.getstring("customer_num") + ")"); } } catch (Exception e) { System.out.println("ERROR: Exception raised: " + e.getmessage()); e.printstacktrace(); } // end catch 33

34 Conclusion Java offers a standard way of accessing data. Java is working in a distributed environment. Frameworks simplify the developers life. 34

35 Complexity & Features Difficult Eclipse Java SE 5 Zend Framework? Java J2EE 4GL PHP 5 Java EE 5 Easy PHP OO in PHP 4 Level of complexity / feature of languages over time

36 And now Come to see me in San Jose (May 2007) Full Java Educational Seminar (you need to stand me for 3 hours) Introduction to EJB3 dev. with IDS and Viper I think I have a session or two on XML (Give me good marks so I can be selected as best speaker of the conference and beat Darryl, Lester and Art - previous speakers and enter Hall of Fame). 36

37 And now (seriously) Download Eclipse (I guess you all have IDS already) Get a book (O Reilly has quite a few great books) Join the development-tools forum on IIUG web site Get started with a few examples Come back to me 37

38 Introduction to Java Development with IDS Thanks for your patience Come back to me 38

4GL to EGL Hype or Reality

Session: I02 4GL to EGL Hype or Reality Jean Georges Perrin IIUG Monday, October 2 nd 2006 13:30 14:30. Platform: IDS, EGL 1 Agenda Who Am I EGL Overview 4GL to EGL Conversion Partner Technology Summary