Composition: Why is the compiler screaming

[africanhacker]

Why is my IDE refusing to accept this? I am trying to use composition here. Elsewhere in the code I have created a cheese object and it is its displayProductDetails method that I am calling.

 public String printDescription(int productIndex){
	       
	        int y = productIndex;
	        if(y == 0){
	            
	            public String displayProductDetails(){ 
                            String x;
	                    x = [I]cheese[/I].displayProductDetails(); 
	                    return x;
	                }
	            
	            
	        }
	       
	   }

[sunde887]

did you name the instance variable that you got through composition cheese? Or did you name it something else?

public class Composition{
  Class1 cheese;  //<--is this named cheese?
  public String printDescription(){
    String x;
    x = cheese.displayProductDetails();
  }
}

[africanhacker]

private Products cheese = new Products("Cheese", 2.33, "cheese001", "Sour Russian Goat Cheese", false, false);

Yes I did name it cheese, and I have created this object in the same class as the code that is failing.

[sunde887]

Ill probably need to see more of the code, first, however; what compiler errors are you getting?

[africanhacker]

I am getting an illegal start of expression error.

[sunde887]

Can you paste the exact error(copy/paste) please?

[sunde887]

public String displayProductDetails(){ 
                            String x;
	                    x = cheese.displayProductDetails(); 
	                    return x;
	                }

your error is here. Think about it and see if you realize why.

Look at the whole posted snippet in your original post, and read the part I just posted and you should be able to figure it out, if you can't let me know.

[JosAH]

Why is my IDE refusing to accept this? I am trying to use composition here. Elsewhere in the code I have created a cheese object and it is its displayProductDetails method that I am calling.

 public String printDescription(int productIndex){
	       
	        int y = productIndex;
	        if(y == 0){
	            
	            public String displayProductDetails(){ 
                            String x;
	                    x = [I]cheese[/I].displayProductDetails(); 
	                    return x;
	                }
	            
	            
	        }
	       
	   }

You're trying to define method displayProductDetails() inside the body of another method. Java doesn't support that.

kind regards,

Jos

[africanhacker]

@Sunde887
For fear of sounding stupid I will keep what I am thinking is the problem to myself. In fact my thoughts are not at all clear. Can you please let me know what is going on.

All my mind could think of was that there was no return to the first method. But I know that is probably not the reason.

And what of what Josah is saying as regards defining a method inside another method?

[sunde887]

What jos said was exactly what I was hinting at as well,

In your original snippet, you posted a method, where inside the method you tried defining a new method, and this causes an error, because you can't(as jos said), define a method inside other methods.

[africanhacker]

Thank you for your help. This is all quite frustrating but I will have to rethink this one way or the other.

[JosAH]

Thank you for your help. This is all quite frustrating but I will have to rethink this one way or the other.

There's not much to think about; you tried to do this:

public class YourClass {
   public String printDescription(int productIndex){
      public String displayProductDetails() { ... }
   }
}

As I wrote before: you can't do that; make it look like this:

public class YourClass {
   public String printDescription(int productIndex){ ... }
   public String displayProductDetails() { ... }
}

kind regards,

Jos