Question

Basically I want to create a data structure of values already known at compile time. In C I’d do it like this:

struct linetype { int id; char *descr; };

static struct linetype mylist[] = {
    { 1, "first" },
    { 2, "second" }
};

The only soultion I have found in Java involves creating the array at runtime:

public class Outer {

    public class LineType {
        int id;
        String descr;

        private LineType( int a, String b) {
          this.id = a;
          this.descr = b;
        }
    }

    LineType[] myList = { 
        new LineType( 1, "first" ),
        new LineType( 2, "second" ),
    };

This appears cumbersome and ineffective (when the structures get long and complex). Is there another way?

(NB: please disregard any syntax errors as this is only sample code created for this question. Also, I am aware a String is somethign else than a character pointer pointing into the data segment. However, the argument works with primitive data types as well).

Answer 1

You have to make LineType a static class:

public class Outer {

    public static class LineType {
        int id;
        String descr;

        private LineType( int a, String b) {
          this.id = a;
          this.descr = b;
        }
    }

    static LineType[] myList = { 
        new LineType( 1, "first" ),
        new LineType( 2, "second" ),
    };
}