1. Server-Side Scripting with JSP (2) ISYS 350

2. Java Array Examples of declaring an array: – int[] anArray = new int[10]; 10 elements index from 0 to 9 – double[] anArrayOfDoubles = new double[10]; – String[] anArrayOfStrings = new String[10]; – int[] anArray = { 100, 200, 300, 400, 500, 600, 700, 800, 900, 1000};

3. Creating a listbox of rates double[] rates= {0.03,0.04,0.05,0.06,0.07}; String[] displays={"3%","4%","5%","6%","7%"}; out.println( "Select interest rate: "); for (int i = 0; i <= rates.length-1; i++) { out.println(" " + displays[i] + " "); } out.println( " ");

4. Compute Future Value: Process form with controls Created Using JSP Code: Note this page is a jsp page

5. JSP code to create the form Enter present value: <% double[] rates= {0.03,0.04,0.05,0.06,0.07}; String[] displays={"3%","4%","5%","6%","7%"}; out.println( "Select interest rate: "); for (int i = 0; i <= rates.length-1; i++) { out.println(" " + displays[i] + " "); } out.println( " "); double[] yearValues= {10,15,30}; String[] yearLabels={"10-year","15-year","30-year"}; out.println( "Select year: "); for (int i = 0; i <= yearValues.length-1; i++) { out.println(" " + yearLabels[i] + " "); } %>

6. JSP Code to process the form <% String myPV, myRate, myYear; myPV=request.getParameter("PV"); myRate=request.getParameter("Rate"); myYear=request.getParameter("Year"); double FV, PV, Rate, Year; PV=Double.parseDouble(myPV); Rate=Double.parseDouble(myRate); Year=Double.parseDouble(myYear); FV=PV*Math.pow(1+Rate,Year); out.println("FutureValue is:"+ FV); %>

7. Testing if two strings are equal The equals() or equalsIgnoreCase method should be used to determine whether two objects have the same values. String string1 = "foo"; String string2 = "Foo"; if (string1==string2) //if (string1.equals(string2)) //if (string1.equalsIgnoreCase(string2)) { out.println("The two strings are equal."); } else { out.println("The two strings are not equal."); }

8. Java Date Processing: Date Class Date class: – Define a date object: Date myDate; – Define a date object with the current date: Date currentDate = new Date(); – getTime method: return the date in milliseconds since 1/1/1900

9. Java Date Processing: DateFormat class DateFormat class is used to define a date format to display a date object or parsing a date/time string to create a date object. Define a date format: – DateFormat formatter = new SimpleDateFormat("MM/dd/yy"); To print a data object: – out.print("Current date is: " + formatter.format(currentDate)); To parse a date string: – myDate=formatter.parse(request.getParameter("txtDa te"));

10. Import Java Class Example: Display Current Date Time Import java.util.Date – Define a Date type variable: – Date currentDate = new Date(); Display in textbox using JSP expression: The time is: ">

11. Date to Date Format Import class: – – Define a format: SimpleDateFormat formatter = new SimpleDateFormat("MM/dd/yy"); – Convert: Example: Display a date with date format: String displayDate = formatter.format(currentDate);

12. Define Date Format Letter Date or Time Component Presentation Examples G Era designator Text AD y Year Year 1996; 96 M Month in year Month July; Jul; 07 w Week in year Number 27 W Week in month Number 2 D Day in year Number 189 d Day in month Number 10 F Day of week in month Number 2 E Day in week Text Tuesday; Tue a Am/pm marker Text PM H Hour in day (0-23) Number 0 k Hour in day (1-24) Number 24 K Hour in am/pm (0-11) Number 0 h Hour in am/pm (1-12) Number 12 m Minute in hour Number 30 s Second in minute Number 55 S Millisecond Number 978 z Time zone General time zone Pacific Standard Time; PST; G MT-08:00 Z Time zone RFC 822 time zone -0800

13. Calculating Days between Current Date and Entered Date Using the getTime() method Enter a date:

14. computeDate.jsp <% Date currentDate = new Date(); Date myDate; DateFormat formatter = new SimpleDateFormat("MM/dd/yy"); myDate=formatter.parse(request.getParameter("txtDate")); out.print(currentDate +" "); out.print("Current date is: " + formatter.format(currentDate)+" "); out.print("Entered date is: " + formatter.format(myDate)+" "); out.print ("Days between = " + (currentDate.getTime()- myDate.getTime())/(24*60*60*1000)+" "); DateFormat yearFormat=new SimpleDateFormat("yyyy"); DateFormat monthFormat=new SimpleDateFormat("MM"); DateFormat weekDayFormat=new SimpleDateFormat("E"); out.print(yearFormat.format(currentDate)+" "); out.print(monthFormat.format(currentDate)+" "); out.print(weekDayFormat.format(currentDate)+" "); %>

15. Java Servlet

16. What is Java Servlet? It is a java class that serves a client request and receives a response from the server. Servlets are most often used to: Process or store data that was submitted from an HTML form Provide dynamic content such as the results of a database query. It is not a web page and cannot be opened by itself. A servlet is called by a HTML form’s action attribute:

17. Adding a Servlet Servlet is a class with a “java” extension: – Ex: FVServlet.java It must belong to a package: – Add a new package – Then add a new servelet – Ex:ServletPackage FVServlet.java

18. Servlet’s processRequest Method This method use the same request and response objects as JSP. For example, it uses the request.getParameter method to read the data submitted with http request: – myPV=request.getParameter("PV"); It uses the out.println statement to send HTML code to browser: out.println(" ");

19. Example: Future Value Calculator: Requesting FVServlet servlet Enter present value: Select interest rate: 4% 5% 6% 7% 8% Select year: 10-year 15-year 30-year

20. FVServlet protected void processRequest(HttpServletRequest request, HttpServletResponse response) String myPV, myRate, myYear,qString; myPV=request.getParameter("PV"); myRate=request.getParameter("Rate"); myYear=request.getParameter("Year"); double FV, PV, Rate, Year; PV=Double.parseDouble(myPV); Rate=Double.parseDouble(myRate); Year=Double.parseDouble(myYear); FV=PV*Math.pow(1+Rate,Year); out.println("FutureValue is:"+ FV);

21. Servlet: depTableServlet to create straight line depreciation table Straight Line Depreciation Table Enter Property Value: Enter Property Life:

22. String strValue, strLife; strValue=request.getParameter("pValue"); strLife=request.getParameter("pLife"); double value, life, depreciation,totalDepreciation=0; value=Double.parseDouble(strValue); life=Double.parseDouble(strLife); NumberFormat nf = NumberFormat.getCurrencyInstance(); out.println("Straight Line Depreciation Table" + " "); out.println("Property Value: "); out.println("Property Life: "); depreciation=value/life; totalDepreciation=depreciation; out.println( " "); out.println(" Year Value at BeginYr "); out.println(" Dep During Yr Total to EndOfYr "); out.println(" "); for (int count = 1; count <= life; count++) { out.write(" "); out.write(" " + count + " "); out.write(" " + nf.format(value) + " "); out.write(" " + nf.format(depreciation) + " "); out.write(" " + nf.format(totalDepreciation) + " "); value -= depreciation; totalDepreciation+=depreciation; }