The EventObject class is the base class for transferring events in Java (see Tip “Understanding the Listener Pattern”). It provides these methods: public EventObject (Object source) // Constructor. The “source”

A bit of randomness can help keep your Web site from getting stale. You can use the JavaScript rand() function to display random text or a random image. function goRand()

There are two types of const data storage: true const and contractual const. const int cn = 5; // true const A contractual const variable is a non-const one, which

Chances are you’ll need the routines that you write in Visual InterDev 6 in other pages. Once you debug a subroutine, you can add it to the Visual InterDev 6

If you use JavaScript rollover images on your Web pages, it’s a good idea to preload them in order to reduce lag time while the image downloads. Non-preloaded images won’t

The major browsers speed up the loading of Web pages by storing a local copy of visited pages in what is called the cache. This works well for surfing the

To improve performance in your Active Server Pages, try to minimize the amount of server script present. From a design point of view, putting extensive code and business rules in

Often times you may have include files on your Web site that store textual information whose content varies, but that are shown in a layout that remains constant (for example,

It is implementation-dependent whether the destructors of local objects are invoked when an uncaught exception occurs. To ensure that destructors of local objects are invoked in this case, you can

An anonymous union declared in a named namespace or in the global namespace has to be explicitly declared static: static union { int num; char *pc; }; //anonymous union in

The Listener pattern is commonly used in the AWT since JDK 1.1. In fact, the Listener has been the base for the event handling mechanism for UI events in Java.

Servlets provide a more effective mechanism of achieving the functionality offered by CGI (Common Gateway Interface) scripts. CGI was one of the first techniques for creating dynamic Web pages by

If you are utilizing Internet Information Server (IIS) 4 and Microsoft Index Server, be careful which directories you set up to be traversed by Index Server. You likely do not

All Java programmers probably know what Java applets are and how they differ from Java applications. After all applets were Java’s gateway into the Internet. Servlets are Java’s entry into

There are many ways to call a JavaScript function in an HTML document. One way is inside an anchor tag. Any function that is listed in the portion of the

Don’t like that plain search results page that comes up when using index server, when the rest of your site looks so nice? The results page is a file with

As far as design is concerned, dynamic_cast should be preferred to typeid because the former enables more flexibility and extensibility. Notwithstanding that, the runtime overhead of typeid can be less

You can start a thread in Java by either implementing the java.lang.Runnable interface or by extending the java.lang.Thread class (see Tip “Weaving Threads”). How do you decide which mechanism to

Question: Imagine an MDI application where the MDIFrame has many MDIChild forms?each one derived from TBlueForm class. The TBlueForm class has a public method named ChangeColor which only makes the

Question: What is the best way to do a database report?in other words print a database? I have been having serious trouble with QuickRep. I specify the dataset but still

Question: How do I save my new database at run time to a new file? I’m using a paradox database?DBGrid, and a table and data source control. Answer: Use TTable’s

Question: I have set up a paradox table for multiple user access using the Netdir method, but when I post a record other users cannot see the changes until the

Question: Can you recommend resources to learn how to tackle 16-bit and 32-bit programming in Delphi? Answer: A number of good books that I’ve read include: All of Charlie Calvert’s

When you type inside the element in Netscape Navigator 4.5, the text scrolls horizontally. You need to press Enter to create a new line. Internet Explorer 4 doesn’t require a

Active Server Pages that utilize databases like SQL Server are no different than conventional programs in that they will experience a performance boost when you use stored procedures instead of

C++ statements can be broken into more than a single line. However, you cannot break literal strings such as printf() format string, macros, or literals. When you need a long

Java’s Socket class gives you control over how a socket handles queued data when it closes. This linger-on-close option allows you to dictate whether you want the socket to send

If you use the intrinsic VB Dir$ function to check for the existence of a certain file, then subsequently try to remove the directory where the file is found using

How many times have you had to control the same processes with both command buttons and corresponding menus? I expect you’d say “many,” which means you’ve had to set the