//: c10:AssociativeArray.java // Associates keys with values. // From 'Thinking in Java, 3rd ed.' (c) Bruce Eckel 2002 // www.BruceEckel.com. See copyright notice in CopyRight.txt. package c10; import com.bruceeckel.simpletest.*; public class AssociativeArray { private static Test monitor = new Test(); 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; } 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")); monitor.expect(new String[] { "Too many objects!", "sky : blue", "grass : green", "ocean : dancing", "tree : tall", "earth : brown", "sun : warm", "dancing" }); } } ///:~