findPerimeterOctagon()

Step 1: Understand the problem

To find the perimeter of an octagon, we need a formula. The formula to calculate the perimeter of a regular octagon is P=8*s where s represents the length of one side. If we know the length of one side, we can easily find the perimeter. In this function, we will assume that we have been given the side length as an input.

double sideLength; 

Step 2: Setting up the function

We begin by setting up our function named 'findPerimeterOctagon' that takes a double as a parameter. This parameter represents the length of the side of our octagon.

 public static double findPerimeterOctagon(double sideLength) { 
 } 

Step 3: Compute Perimeter

Within this function, we will calculate the perimeter of the octagon. Using the formula P=8*s, we'll multiply the side length by 8.

public static double findPerimeterOctagon(double sideLength) { 
   double perimeter = 8*sideLength; 
} 

Step 4: Return Result

After we have computed the perimeter, we return this value from our function.

public static double findPerimeterOctagon(double sideLength) { 
  double perimeter = 8*sideLength; 
  return perimeter; 
} 

Conclusion:

In conclusion, we have implemented a function in Java to calculate and return the perimeter of an octagon given the length of one of its sides. Here is the full code:

public class Main { 
   public static void main(String[] args) { 
       double sideLength = 5; 
       double result = findPerimeterOctagon(sideLength); 
       System.out.println("The perimeter of the octagon is " + result); 
   } 

   public static double findPerimeterOctagon(double sideLength) { 
       double perimeter = 8*sideLength; 
       return perimeter; 
   } 
}