OBJECT ORIENTED CONCEPTS IN JAVA PPT

Any version before J2SE 5.0 does NOT have this feature! 15Encapsulation of classes into a packageAdd a class into a package — two steps:1. put the name of the package at the top of your source file2. put the files in a package into a subdirectory which matches the full package namestored [r]

Building the PageNavigator Class 51The remaining four variables are simply text strings that label the con-trols used in the navigator, and they can be changed as the user sees fit://text for navigationprivate $strfirst = "|<";private $strnext = "Next";private $strprevious = "Prev"[r]

In sum, you will design a page navigator that will look something like Figure 7-1.Figure 7-1: Your page navigator designIn this particular example, the maximum number of pages shown by your navigator is 7. The total number of pages is 12, and the link to the current page, 4, is disabled (indi[r]

you’ve seen, you needed to make surprisingly few changes to this class in order to implement some of the key changes introduced with PHP 5. Certainly, the changes described in this chapter are not the only changes to PHP’s OO capabilities; however, one of them—the use of access modifie[r]

page length.As noted on many occasions, the real value of objects is in their reusability. Through the use of CSS, you’re able to adjust the appearance of the page navigator to match it to a variety of situations. By using span and div tags, you can manipulate the look and feel of the navigat[r]

can also bring improvement. In this chapter we’ll use inheritance to improve the MySQL classes developed in Chapter 9, by simplifying error trapping and by modifying the behavior of the MySQLResultSet class.Trapping errors is not a job that developers approach with enthusiasm. It is te[r]

Nguyễn Đức Hiển – Bài giảng Lập trình Java1Java Object-Oriented ProgrammingGiảng viên : Nguyễn Đức HiểnEmail : ndhien@udn.vnWebsite :Thời lượngLý thuyết : 2 tín chỉ (30 tiết)Thực hành + thảo luận : 1 tín chỉNguyễn Đức Hiển – Bài giảng Lập trình Java2Chương 8L[r]

DesignOOP doesn’t eliminate the need for systems analysis. It’s easy to forget about this step and to just start coding, especially when dealing with a fairly simple task. However, a little forethought during the design stage will reap benefits later on, so make sure you have a clear idea of what yo[r]

available for download at the companion website. This code can be put to work immediately in a variety of situations.The code takes full advantage of the capabilities of PHP 5 but, where possible, a PHP 4 version of the code is also provided, because you don’t always have a choice about where[r]

1WHAT A TANGLED WEB WE WEAVECreating a web page ain’t what it used to be. Setting up a website today usually means incorporating numerous technologies, among them (X)HTML, CSS, JavaScript, SQL, and a server-side scripting language. But that’s not all—a web page also runs within a browser. There are[r]

OO enthusiasts are usually eager to point out the big ways in which OOP is superior to procedural programming, through capabilities such as inheri-tance, for instance. True enough, but probably of more importance is the fact that once you have a class, providing that the basic design is sound[r]

immediately following the code that may cause problems. As you can see in Listing 10-5, an Exception may be caught many lines away from where the problem occurs, which is an advantage because it makes for more readable and maintainable code.Implementing an InterfaceInheriting from an existing[r]

//////////////////////////////////////////////////////////////Listing 15-4: Extending the SQLiteDatabase classIn each case, the query method of the parent class, SQLiteDatabase, is redefined to include a test of the return value.Error MessagesThe comment immediately inside each method definition sho[r]

OOPHP_02.book Page 136 Friday, May 5, 2006 2:25 PMCreating Documentation Using the Reflection Classes 137Methods of all levels of visibility are passed to the show_methods function to handle the details of displaying method descriptions. Here is the prototype for this function:function show_methods([r]

Drivers are available for all the major databases supported by PHP—Oracle, Microsoft SQL Server, PostgreSQL, ODBC, SQLite, and all versions of MySQL up to version 5. So, if you use a variety of different databases, PDO 1 www.zend.com/zend/week/week207.php#Heading6. (Accessed April 14, 2006.)OOPHP_0[r]

More Magic Methods 121While looping through the array of players each individual player is cloned and added to a new array. Doing this creates a separate array for the cloned team. After making these changes, running the code in Listing 13-6 now yields this output:Rovers Array ( [0] =>[r]

Likewise, any other operators or functions not used by MySQL would have to be changed.Another option would be to use standard SQL wherever possible. The date manipulation functions could be ignored, and this task performed from within PHP. That’s a choice each developer will have to make for themsel[r]

APIs_Reference.html. If you plan to make extensive use of the Google API, then the information in the reference file is invaluable. Among other things, it shows the legal values for a language-specific search, and it details some of the API’s limitations. For instance, unlike a search initiat[r]

syndication that is widely used by various newsgroups but more commonly encountered in the form of a blog. An RSS file is an Extensible Markup Language (XML) formatted file that can be read using the SimpleXML extension to PHP 5. All you need in order to read an RSS feed is a little kn[r]

similar fashion the __get method will retrieve name. Is It Worth It?Magic set and get methods are introduced as a convenience, but it is certainly questionable whether they are worth the effort. Encouraging the use of undefined data members can easily lead to difficulties when debugging. For instanc[r]