Create your own Associate Array in Java

/*www  .  j  ava  2 s  .c o  m*/
public class Main{
  public static void main(String[] args) {
    AssociativeArray map = new AssociativeArray(6);
    map.put("sky", "blue");
    map.put("grass", "green");
    map.put("ocean", "dancing");
    map.put("tree", "tall");
    map.put("earth", "brown");
    map.put("sun", "warm");
    try {
      map.put("extra", "object"); // Past the end
    } catch (ArrayIndexOutOfBoundsException e) {
      System.out.println("Too many objects!");
    }
    System.out.println(map);
    System.out.println(map.get("ocean"));

  }
}
class AssociativeArray {

  private Object[][] pairs;

  private int index;

  public AssociativeArray(int length) {
    pairs = new Object[length][2];
  }

  public void put(Object key, Object value) {
    if (index >= pairs.length)
      throw new ArrayIndexOutOfBoundsException();
    pairs[index++] = new Object[] { key, value };
  }

  public Object get(Object key) {
    for (int i = 0; i < index; i++)
      if (key.equals(pairs[i][0]))
        return pairs[i][1];
    throw new RuntimeException("Failed to find key");
  }

  public String toString() {
    String result = "";
    for (int i = 0; i < index; i++) {
      result += pairs[i][0] + " : " + pairs[i][1];
      if (i < index - 1)
        result += "\n";
    }
    return result;
  }

}