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Perl & CGI tutorials
 ::   Intro to Perl/CGI and HTML Forms
 ::   Intro to Windows Perl
 ::   Intro to Perl 5
 ::   Intro to Perl
 ::   Intro to Perl Taint mode
 ::   Sherlock Holmes and the Case of the Broken CGI Script
 ::   Writing COM Components in Perl

Java tutorials
 ::   Intro to Java
 ::   Cross Browser Java

Misc technical tutorials
 ::   Intro to The Web Application Development Environment
 ::   Introduction to XML
 ::   Intro to Web Design
 ::   Intro to Web Security
 ::   Databases for Web Developers
 ::   UNIX for Web Developers
 ::   Intro to Adobe Photoshop
 ::   Web Programming 101
 ::   Introduction to Microsoft DNA

Misc non-technical tutorials
 ::   Misc Technopreneurship Docs
 ::   What is a Webmaster?
 ::   What is the open source business model?
 ::   Technical writing
 ::   Small and mid-sized businesses on the Web

Offsite tutorials
 ::   ISAPI Perl Primer
 ::   Serving up web server basics
 ::   Introduction to Java (Parts 1 and 2) in Slovak

 

Introduction to Web Programming
Arrays  
  • Like Perl, Java has a built in array class which you can use to hold multiple values so long as those values areof the same data type.

  • However, in Java, arrays are much morerestrictive. For example, you may not change the size of anarray once you have created it. To add elements to an array dynamicallyyou actually have to create a new, larger array and copy the old arrayinto the new one using arrayCopy() in the java.lang.System class.

  • For a dynamically resizable data structure,you may want to look to the Vector class in the java.utilpackage.

  • However, for cases in which you do not need to dynamically resize your data structure, arrays workgreat. Like Perl, Java provides a zero-based array which isdefined much as variables are. You first declare what type of data will be stored in an array, give the array a name, and then define how large it is. Consider the following example:

    int[] intArray = new int[50];

  • This array would hold 50 ints numbered from 0-49.

  • Filling and extracting values from anarray is the same process as it was for Perl. Consider the following example:

    int[] intArray = new int[50];
    for (int i = 0; i < 50; i++)
      {
      intArray[i] = i;
      }
    for (int i = 0; i < 50; i++)
      {
      System.out.println("Value: " + intArray[i]);
      }
    

  • Java also allows you to define an arrayat time of initialization such as in the following example:

    int[] intArray = {0,1,2,3,4};

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