MDCFUG Is Java in Your Future

1
MDCFUGIs Java in Your Future?

• Tyler Williams
• Principal Consultant _at_ dataTerrace
• twilliams_at_dataterrace.com

2
Agenda

• The Java Learning Curve
• Why This is a Good Thing
• J2EE Breakdown
• Sample Program
• Q A

3
My Background

• Consultant 2 1/2 years
• Certified CF Developer
• 4 years CF
• 1 year Java
• 6 years Oracle

4
Java Language Barriers

• Non-Tag Based
• Lower Level Than CF (more code)
• Object Oriented
• Strongly Typed Case Sensitive
• Large Function Library
• Powerful, Complex and Less Forgiving

5
Power of Perception

• CF is Easy to Learn
• Ease of Entry Brings Less Qualified Programmers
  to the Language
• More Low Grade Programs are Written
• CF Language Gets a Bad Rap

6
The Good Side of Barriers

• Less Competition
• Higher Rates
• Protected Reputation

7
J2EE - Enterprise Java

• Server-side Web Development
• Standard Created by Sun
• Many Competing Application Servers
• App Servers Must Pass a Compatibility Test Suite
• Vendors Add Extensions JSP Tag Libraries

8
J2EE Technologies

• Lower Complexity
• Java Server Pages (JSP)
• Servlets
• Higher Complexity
• JDBC (Database Connectivity)
• Enterprise Java Beans (EJB)
• Java Messaging Service (JMS)

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JSP Example

• String str "8th"
• Simple JSP Page
• Welcome to the dimension

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Servlet Example

• import java.io.
• import servlet.
• import servlet.http.
• public class SimpleServlet extends HttpServlet
• public void doGet (HttpServletRequest req,
  HttpServletResponse res)
• throws ServletException, IOException
• response.setContentType(text/html)
• PrintWriter out response.getWriter()
• out.println(Simple Servlet
  Example)
• out.println()
• String str "8th"
• out.println(Welcome to the str
  dimension)
• out.println()

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JDBC Example

• Class.forName("oracle.jdbc.driver.OracleDriver")
  
• String stUrl_ "jdbcoraclethin_at_host1521sid"
• Connection connection_ DriverManager.getConnecti
  on(stUrl_, username",password")
• PreparedStatement statement_ connection_.prepare
  Statement("SELECT fname, lname FROM EMPLOYEE")
• ResultSet rs statement_.executeQuery()
  //execute query
• while (rs.next())
• String firstName rs.getString(1)
• String lastName rs.getString(2)
• strOut strOut firstName " " lastName
  "
  "
• rs.close()
• statement_.close()
• connection_.close()

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CF Comparison

• SELECT fname, lname FROM EMPLOYEE
• main_select.fname main_select.lname

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JDBC Metadata

• getColumnCount - Returns the number of columns in
  this Result Set
• getColumnName - Get the designated column's name
• getColumnType - Retrieve the designated column's
  SQL type
• isAutoIncrement - Indicates whether the
  designated column is automatically numbered, thus
  read-only

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Model-View-Controller (MVC)

• Model Data JDBC
• View Presentation JSP
• Controller Framework Servlet

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MVC Flow
Client
1) Client submits a page request 2) Servlet
interprets request 3) Servlet retrieves
necessary info from JDBC 4) Servlet hands off
request and details to JSP for formatting and
presentation
Servlet
JDBC
JSP
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Complete MVC Example

• DimensionApp.java (Servlet)
• DimensionVO.java (JDCB Class)
• Display.jsp (JSP)

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DimensionApp.java

• import java.io.
• import javax.servlet.
• import javax.servlet.http.
• import DimensionVO
• public class DimensionApp extends HttpServlet
• public void service (HttpServletRequest req,
  HttpServletResponse res)
• throws ServletException, IOException
• DimensionVO dvo new DimensionVO()
• String mydim dvo.getDimension()
• req.setAttribute("dimension", mydim)
• RequestDispatcher rd
• rd getServletContext().getRequestDispatche
  r("/jsp/Display.jsp")
• rd.forward(req, res)

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DimensionVO.java

• import java.sql.
• import java.util.
• import java.io.
• public class DimensionVO
• String strOut
• String stUrl_ "jdbcodbcmdcfug"
• private Connection connection_ null
• private PreparedStatement statement_ null
• private ResultSet rs
• public String getDimension ()
• throws IOException
• try
• Class.forName("sun.jdbc.odbc.JdbcOdbcDriver")
• Connection connection_ DriverManager.getConne
  ction(stUrl_, "Admin","")
• statement_ connection_.prepareStatement("SELE
  CT dimension FROM DIMENSIONS")
• rs statement_.executeQuery() //execute
  query
• String mydim rs.getString(1)
• strOut mydim
• rs.close()

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Display.jsp

• sion")
• MVC Example
• nbsp
• Welcome to the str dimension

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Java Resources

• Javas Home _at_ Sun
• http//java.sun.com
• Java Portals
• http//www.theserverside.com
• http//www.jguru.com/
• Suns JDBC Tutorial
• http//developer.java.sun.com/developer/onlineTra
  ining/Database/JDBC20Intro/

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Java Bookshelf

• The Java Language
• Java in a Nutshell - Flanagan
• Servlets/JSP
• Java Servlet Programming - Hunter
• Web Development With JavaServer Pages -
  Fields/Kolb
• Core Servlets and JavaServer Pages - Hall
• J2EE Application Architecture
• Core J2EE Patterns - Alur