Getters and Setters
The unique class methods known as getters and setters are used to read and write access to an object’s properties. The setter method is used to set or initialize the appropriate class fields, while the getter function is used to get or retrieve the value of the variable. All classes have getter and setter methods assigned to them by default. By explicitly declaring the getter and setter methods, we can, nevertheless, override the default ones.
Defining a getter
By utilizing the get keyword without a parameter and a proper return type, we may define the getters method.
Syntax
return_type get field_name{
}
Defining a setter
The set keyword can be used to declare the setter method with a single parameter and no return type.
Syntax
set field_name {
}
Example
class Student {
String stdName;
String branch;
int stdAge;
// getter method
String get std_name
{
return stdName;
}
void set std_name(String name)
{
this.stdName = name;
}
void set std_age(int age) {
if(age> = 20){
print("Student age should be greater than 20")
}else{
this.stdAge = age;
}
}
}
int get std_age{
return stdAge;
}
void set std_branch(String branch_name) {
this.branch = branch_name;
}
int get std_branch{
return branch;
}
}
void main(){
Student std = new Student();
std.std_name = 'John';
std.std_age = 24;
std.std_branch = 'Computer Science';
print("Student name is: ${std_name}");
print("Student age is: ${std_age}");
print("Student branch is: ${std_branch}");
}
Output
Student name is: John
Student age is: 24
Student Branch is: Computer Science
Example
class Car {
String makedate;
String modelname;
int manufactureYear;
int carAge;
String color;
// Getter method
int get age {
return carAge;
}
// Setter Method
void set age(int currentYear) {
carAge = currentYear - manufactureYear;
}
// defining parameterized constructor
Car({this.makedate,this.modelname,this.manufactureYear,this.color,});
}
//Age here is both a getter and a setter. Let's see how we can use it.
void main() {
Car c =
Car(makedate:"Renault 20/03/2010",modelname:"Duster",manufactureYear:2010,color:"White");
print("The car company is: ${c.makedate}");
print("The modelname is: ${c.modelname}");
print("The color is:${c.color}");
c.age = 2020;
print(c.age);
}
Output
The car company is: Honda 20/03/2010
The modelname is: City
The color is: White
10
Explanation
The getter and setter methods are defined before the constructor in the code above.
