Constructor (object-oriented programming): Difference between revisions

Revision as of 08:40, 29 November 2019

Revision as of 17:02, 1 December 2019

Line 107:

class Example

{

Example() //non Non-parameterized constructor

{

this(1); //calling Calling of constructor

System.out.println("0-arg-cons");

}

Example(int a) //parameterized Parameterized constructor

{

System.out.println("1-arg-cons");

}

}

public static void main(String[] args)

{

Line 538 ⟶ 539:

<source lang="perl6">

class Person {

has Str $.first-name is required; # firstFirst name (a string) can only be set at

# construction time (the . means "public").

has Str $.last-name is required; # lastLast name (a string) can only be set at

# construction time (a ! would mean "private").

has Int $.age is rw; # ageAge (an integer) can be modified after

# construction ('rw'), and is not required

# during the object instantiation.

# createCreate a 'full-name' method which returns the person's full name.

# thisThis method can be accessed outside the class.

method full-name { $!first-name.tc ~ " " ~ $!last-name.tc }

# createCreate a 'has-age' method which returns true if age has been set.

# thisThis method is used only inside the class so it's declared as "private"

# by prepending its name with a !

method !has-age { self.age.defined }

# checkCheck custom requirements

method TWEAK {

if self!has-age && $!age < 18 { # noNo under 18

die "No person under 18";

}

Line 592 ⟶ 593:

class Person

{

private string $name;

public function __construct(string $name) : void

{

$this->name = $name;

}

public function getName() : string

{

return $this->name;