example illustrating the complete lack of lightweight data modelling in Java

JavaMapsAndLists.java

import java.util.List;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Map;
import java.util.HashMap;

public class JavaMapsAndLists {
  public static void main(String [] args) {
    List<Integer> someItems = Arrays.asList(new Integer[] {1, 2, 3, 4});
    for (Integer item : someItems) {
        System.out.println(item);
    }
    Map<String, String> someMapping = new HashMap<String , String>() {{
        put("ST", "started");
        put("IP", "in progress");
        put("DN", "done");
    }};
    for (Map.Entry<String, String> entry : someMapping.entrySet()) {
        String key = entry.getKey();
        String value = entry.getValue();
        System.out.println(key + " => " + value);
    }
  }
}

Clojure, a bit closer to other examples: https://gist.github.com/amontalenti/8117294

Here's a version in haskell, though I am not really a haskeller, so I'm sure it can be better: https://gist.github.com/lgastako/8117999

Groovy: https://gist.github.com/amontalenti/8322307

You can do lists this way to make it more concise.

List<Integer> someItems = Arrays.asList(1, 2, 3, 4);