Thread: How to build a List dynamically

Dear Experts

I am looping thru a Result Set from a SQL-Query using the 'while' statement. This is result set is "forward-only", which means can't call the 'first' method to loop it again. Actually I don't want to loop it twice anyway for performance reasons.

Instead my idea is to copy the values into a collection or multi-dimensional array and then scan this list twice to build my final result. (which is a string)

My idea was to use a nested class, but I got a compilation error. In C# one might use a 'struct' to get this done.

What's the deal in Java?

I'd ideally create something like

public class CodeInfo (...3 properties) and then pass that to an arrayList to iterate it...but haven't got it done myself...

Thanks
Roger

A struct is nothing other then a class without methods and only public attributes. If you know how to do it in C# you should also be able to do it in java since these two are hardly different.

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Well, I mastered my problem using a different approach, but I'm still interessted in this, as it's probably "basics":

 
public class Playground {
 
	public class InnerClass {
		public String anything;
		public Integer someNumber;
	}
 
	public static void main(String[] args) {
		// TODO Auto-generated method stub
 
		System.out.println("Test");
 
		InnerClass innerClass = new InnerClass();
 
 
		// final goal: Fill a Collection (ArrayList)
		// with the InnerClass "struct/record"
		// in a loop (while)
 
	}
 
}

Eclipse (Luna, Java 1.7) is saying:

No enclosing instance of type Playground is accessible. Must qualify the allocation with an enclosing instance of type Playground (e.g. x.new A() where x is an instance of Playground).

Of course, sorry it's the line where I try to instantiate the InnerClass (new)

Thanks guys, this was really helpful.