Search results
Results from the WOW.Com Content Network
However, the compiler automatically transforms the code so that the list will "silently" receive objects, while the source code only mentions primitive values. For example, the programmer can now write list. add (3) and think as if the int 3 were added to the list; but, the compiler will have actually transformed the line into list. add (new ...
In this Java example, the Printer class has a print method. This print method, rather than performing the print itself, forwards to an object of class RealPrinter . To the outside world it appears that the Printer object is doing the print, but the RealPrinter object is the one actually doing the work.
It should be possible to define a new operation for (some) classes of an object structure without changing the classes. When new operations are needed frequently and the object structure consists of many unrelated classes, it's inflexible to add new subclasses each time a new operation is required because "[..] distributing all these operations across the various node classes leads to a system ...
Perhaps the most well-known example is C++, an object-oriented extension of the C programming language. Due to the design requirements to add the object-oriented paradigm on to an existing procedural language, message passing in C++ has some unique capabilities and terminologies. For example, in C++ a method is known as a member function.
C++ does not have the keyword super that a subclass can use in Java to invoke the superclass version of a method that it wants to override. Instead, the name of the parent or base class is used followed by the scope resolution operator. For example, the following code presents two classes, the base class Rectangle, and the derived class Box.
Cascading can be implemented using method chaining by having the method return the current object itself. Cascading is a key technique in fluent interfaces , and since chaining is widely implemented in object-oriented languages while cascading isn't, this form of "cascading-by-chaining by returning this " is often referred to simply as "chaining".
A class diagram exemplifying the singleton pattern. In object-oriented programming, the singleton pattern is a software design pattern that restricts the instantiation of a class to a singular instance. It is one of the well-known "Gang of Four" design patterns, which describe how to solve recurring problems in object-oriented software. [1]
import java.util.*; /*This form of importing classes makes all classes in package java.util available by name, could be used instead of the import declaration in the previous example. */ import java.*; /*This statement is legal, but does nothing, since there are no classes directly in package java.