Question

public class SquareTest {
   public static void main(String[] args) {
      
       System.out.println("Number of sides is " + Square.NUM_OF_SIDES);
      
      
       Square s1 = new Square(-5.7f);
      
       System.out.println(s1);
      
       s1.setLength(0.001f);
       System.out.println(s1.getLength());
      
       s1.setLength(-9999);
       System.out.println(s1.getLength());
      
       System.out.println("Number of sides is " + s1.NUM_OF_SIDES);
      
       s1.calculateArea();
      
      
         
   }
}

This topic appears to be stumping me. I now need to call the method to calculate the area and perimeter but when I try to invoke the method I get an error indicating incompatible type.The above code is what I have to call the method on. Not sure what I am missing here.

Answer 1

class Square
{
   private float length;
   public static final int NUM_OF_SIDES = 4; // static constant value
  

//constructor
   public Square(float length)
   {
       this.length = length;
   }

//set and get methods
   public void setLength(float length)
   {
       this.length = length;
   }
   public float getLength()
   {
       return length;
   }
   public float calculateArea()
   {
       return length*length;
   }
   public String toString()
   {
       return "Square : Length : "+length+" Area : "+calculateArea();
   }
  
}
class SquareTest {
  
public static void main(String[] args) {
  
System.out.println("Number of sides is " + Square.NUM_OF_SIDES);
  
  
Square s1 = new Square(-5.7f);
  
System.out.println(s1);
  
s1.setLength(0.001f);
System.out.println(s1.getLength());
  
s1.setLength(-9999f);
System.out.println(s1.getLength());
  
System.out.println(s1);
  
  

}
}

Output:

Number of sides is 4
Square : Length : -5.7  Area : 32.489998
0.001
-9999.0
Square : Length : -9999.0  Area : 9.998E7

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