Latest Thinking In Java Articles - Page 6

Arrays

Most of the necessary introduction to arrays is in the last section of Chapter 4, which shows how you define and initialize an array. Holding objects is the focus of this chapter, and an array is just one way to hold objects. But there are a number of other ways to hold objects, so what makes an array special?

Collections

To summarize what we’ve seen so far, your first, most efficient choice to hold a group of objects should be an array, and you’re forced into this choice if you want to hold a group of primitives. In the remainder of the chapter we’ll look at the more general case, when you don’t know at the time you’re writing the program how many objects you’re going to need, or if you need a more sophisticated way to store your objects. Java provides four types of collection classes to solve this problem: Vector , BitSet , Stack , and Hashtable . Although compared to other languages that provide collections this is a fairly meager supply, you can nonetheless solve a surprising number of problems using these tools.

Summary

Polymorphism means “different forms.” In object-oriented programming, you have the same face (the common interface in the base class) and different forms using that face: the different versions of the dynamically-bound methods.

Upcasting

In Chapter 6 you saw how an object can be used as its own type or as an object of its base type. Taking an object handle and treating it as the handle of the base type is called upcasting because of the way inheritance trees are drawn with the base class at the top.

Latest Developer Videos

More...

Latest CodeGuru Developer Columns

MFC Integration with the Windows Transactional File System (TxF)

The Transactional File System (TxF), which allows access to an NTFS file system to be conducted in a transacted manner through extensions to the Windows SDK API. MFC 10, has been extended to support TxF and related technologies. This support allows existing MFC applications to be easily extended to support kernel transactions.

LINQ to Objects Refresher

LINQ is not only for database access; it’s useful in all manner of scenarios. Read this quick refresher to learn more.

Top White Papers and Webcasts

  • With 81% of employees using their phones at work, companies have stopped asking: "Is corporate data leaking from personal devices?" and started asking: "How do we effectively prevent corporate data from leaking from personal devices?" The answer has not been simple. ZixOne raises the bar on BYOD security by not allowing email data to reside on the device. In addition, Zix allows employees to maintain complete control of their personal device, therefore satisfying privacy demands of valued employees and the …

  • Java developers know that testing code changes can be a huge pain, and waiting for an application to redeploy after a code fix can take an eternity. Wouldn't it be great if you could see your code changes immediately, fine-tune, debug, explore and deploy code without waiting for ages? In this white paper, find out how that's possible with a Java plugin that drastically changes the way you develop, test and run Java applications. Discover the advantages of this plugin, and the changes you can expect to see …

Most Popular Programming Stories

More for Developers

Latest Developer Headlines

RSS Feeds