import java.lang.String; import java.util.StringTokenizer; import java.util.Hashtable; import java.util.GregorianCalendar; /*A simple Java program that illustrates simple I/O for a browser form */ public class javaVisits { /* * Record brief history of Web interactions, using cgi framework. */ public static Hashtable generatePairs (String baseString, String separator){ /* divide the query strings into name=value pieces */ StringTokenizer nameValue = new StringTokenizer (baseString, separator); /* put name=value pieces into hash table for easy retrieval */ Hashtable baseElements=new Hashtable(); while (nameValue.hasMoreTokens()) { String pair = nameValue.nextToken(); if (pair.charAt(0) == ' ') { pair = pair.substring(1, pair.length()); } int pos = pair.indexOf("="); baseElements.put(pair.substring(0, pos), pair.substring(pos+1)); } return baseElements; } public static void main(String[] args) throws Exception { /************************* http header ********************************/ System.out.println("Content-type: text/html"); /************************* cookie processing **************************/ /*** must set any new cookies before printing page cookieElements = generatePairs (args[1], ";"); /* retrieve previous cookie, if it exists */ String numVisitsStr = cookieElements.get("numVisits"); String lastDate = cookieElements.get("lastDate"); /* GregorianCalendar defaults to the current date and time */ GregorianCalendar todaysDate = new GregorianCalendar(); /* next week is 7 days from the current date and time */ GregorianCalendar nextWeek = new GregorianCalendar(); nextWeek.roll(GregorianCalendar.DAY_OF_YEAR, 7); int numVisits; if (numVisitsStr == null) { numVisits = 0; } else { numVisits = new Integer(numVisitsStr).intValue(); } if (lastDate == null) { lastDate = "not known"; } System.out.println("Set-Cookie: numVisits=" + (numVisits+1)); System.out.println("Set-Cookie: lastDate=" + todaysDate.getTime() +"; expires=" + nextWeek.getTime()); System.out.println(); /************************* page header ********************************/ System.out.println(""); System.out.println(""); System.out.println(""); System.out.println(""); System.out.println(""); System.out.println("Title for Visit History"); System.out.println(""); System.out.println(""); System.out.println(""); /**********************************************************************/ /* page title */ System.out.println("

History of Your Interaction with this Web Page

"); /**********************************************************************/ System.out.println("

Query String Information

"); /* processing to put the form data values into a Hashtable */ /* args[0] contains the browser information as composite string */ System.out.println("Here is the query string: " + args[0]); Hashtable queryElements = generatePairs (args[0], "&"); /**********************************************************************/ /* access query-string fields as desired */ System.out.println("

"); System.out.println ("myText field: " + queryElements.get("myText")); System.out.println("
"); System.out.println ("myNumber field: " + queryElements.get("myNumber")); System.out.println("
"); System.out.println ("mySecret field: " + queryElements.get("mySecret")); System.out.println("

"); /**********************************************************************/ System.out.println("

Cookie Information

"); /* cookies identified as part of header processing */ System.out.println("Here is a listing of previously-set cookies: " + args[1]); System.out.println("
"); System.out.println ("numVisits: " + numVisits); System.out.println("
"); System.out.println ("lastDate: " + lastDate); /**********************************************************************/ System.out.println("

Date Information

"); /* date information determined under cookie processing */ System.out.println ("today's date: " + todaysDate.getTime()); System.out.println("
"); System.out.println ("next week's date: " + nextWeek.getTime()); /********************** html/browser footer ***************************/ System.out.println(""); System.out.println(""); } // main(String[]) } // javaVisits