java programming?

Question

ts telling me to do this. 
Define accessor (“getter”) methods called getFunctionChoice and getDescription that return the values of the corresponding fields. The method getDescription takes an integer and returns the description corresponding to the integer. Define the toString() method, which returns the value of the “description” field. 
and this is what I have.
public class Function {

private  double FUNCTION_CHOICE;
		private  String description;

public Function(String index) 
		{ 
		description = index; 
		}

public void setDescription(String description) 
		{ 
		this.description = description;
				if(description.equals(1))
				{
					description = 	"((8x-sqrt(x)/(x^3 - 7x^2 + 15x -9)";
				}
				else if(description.equals(2))
				{
					description = 	"sinx" ;
				}
				else if(description.equals(3))
				{
					description = 	"5/x + 35" ;
				}
				else if(description.equals(4))
				{
					description = 	 "sqrt(x^2+16)-4)/x^2" ;
				}
				else if(description.equals(5))
				{
					description =  "(e^x-1)/x";
				}
		} 
		public static int getDescription(int num)
		{
			return num;
		}
		public double getFunctionChoice()
		{
			return FUNCTION_CHOICE;
			
		}
		public String toString()
		{
			return description;
		}

}

I have no errors, but its not printing what I want it to, does anyone know why? thanks

? · Answer

description = "((8x-sqrt(x)/(x^3 - 7x^2 + 15x -9)";

Here, you are setting the parameter description, not the instance variable description.  I think you'd need to do this:

this.description = "((8x-sqrt(x)/(x^3 - 7x^2 + 15x -9)";

Or maybe you could call the parameter by some other name, to avoid confusion.

Also, isn't the parameter supposed to be an int, not a String?  You're comparing it to various numbers, after all.

java programming?

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