Return type
In computer programming, the return type defines and constrains the data type of the value returned from a subroutine or method. In many programming languages the return type must be explicitly specified when declaring a function.
In the C example:
int calculateSum
the return type is. The program can therefore rely on the method returning a value of type. Various mechanisms are used for the case where a subroutine does not return any value, e.g., a return type of is used in some programming languages:
void sayHello
Returning a value from a method
A method returns to the code that invoked it when it completes all the statements in the method, reaches a return statement, orthrows an exception, whichever occurs first.
To declare a method's return type, it is included in its method declaration. Within the body of the method, the return statement is used to return the value.
Any method declared void does not return a value. It does not need to contain a return statement, but it may do so. In such a case, a return statement can be used to branch out of a control flow block and exit the method and is simply used like this:
return;
If a value from a method declared is returned, a compiler error will occur.
Any method that is not declared must contain a return statement with a corresponding return value, like this:
return returnValue;
The data type of the return value must match the method's declared return type; for instance, one cannot return an value from a method declared to return a.
The method in the class that was discussed in the sections on objects returns an :
class Rectangle
This method returns the integer that the expression evaluates to.
The method returns a primitive type. A method can also return a reference type. For example, in a program to manipulate objects, we may have a method like this:
class Bicycle
class RaceEnvironment
public class BicycleRace