Scrigroup - Documente si articole

Username / Parola inexistente      

Home Documente Upload Resurse Alte limbi doc  

AccessAdobe photoshopAlgoritmiAutocadBaze de dateCC sharp
CalculatoareCorel drawDot netExcelFox proFrontpageHardware
HtmlInternetJavaLinuxMatlabMs dosPascal
PhpPower pointRetele calculatoareSqlTutorialsWebdesignWindows

AspAutocadCDot netExcelFox proHtmlJava
LinuxMathcadPhotoshopPhpSqlVisual studioWindowsXml

Default constructors


+ Font mai mare | - Font mai mic


Trimite pe Messenger
Specifying initialization
Auto increment and decrement
Visual programming and Beans
Performance: Locating the bottleneck
Bitwise operators
Exception matching
Logical operators
Standard Java exceptions: The special case of RuntimeException
AWT Peer Interfaces
Introduction to Swing: Buttons, Icons, Menus

Default constructors

As mentioned previously, a default constructor is one without arguments, used to create a “vanilla object.” If you create a class that has no constructors, the compiler will automatically create a default constructor for you. For example:


class Bird

public class DefaultConstructor

The line

new Bird();

creates a new object and calls the default constructor, even though one was not explicitly defined. Without it we would have no method to call to build our object. However, if you define any constructors (with or without arguments), the compiler will not synthesize one for you:

class Bush

Bush(double d)

Now if you say:

new Bush();

the compiler will complain that it cannot find a constructor that matches. It’s as if when you don’t put in any constructors, the compiler says “You are bound to need some constructor, so let me make one for you.” But if you write a constructor, the compiler says “You’ve written a constructor so you know what you’re doing; if you didn’t put in a default it’s because you meant to leave it out.”

Politica de confidentialitate



Vizualizari: 324
Importanta: rank

Comenteaza documentul:

Te rugam sa te autentifici sau sa iti faci cont pentru a putea comenta

Creaza cont nou

Termeni si conditii de utilizare | Contact
© SCRIGROUP 2022 . All rights reserved

Distribuie URL

Adauga cod HTML in site