//: c08:AssocArray.java
// From Thinking in Java, 2nd Edition
// Available at http://www.BruceEckel.com
// (c) Bruce Eckel 1999
// Copyright notice in Copyright.txt
// Simple version of a Map
import java.util.*;

public class AssocArray extends AbstractMap {
  private ArrayList keys = new ArrayList();
  private ArrayList values = new ArrayList();
  public int size() { return keys.size(); }
  public boolean isEmpty() {
    return keys.isEmpty();
  }
  public Object put(Object key, Object value) {
    int index = keys.indexOf(key);
    if (index == -1) { // Key not found
      keys.add(key);
      values.add(value);
      return null;
    } else { // Key already in table; replace
      Object returnval = values.get(index);
      values.set(index, value);
      return returnval;
    }
  }
  public Object get(Object key) {
    int index = keys.indexOf(key);
    // indexOf() Returns -1 if key not found:
    if(index == -1) return null;
    return values.get(index);
  }
  public Object remove(Object key) {
    int index = keys.indexOf(key);
    if(index == -1) return null;
    keys.remove(index);
    Object returnval = values.get(index);
    values.remove(index);
    return returnval;
  }
  public Set keySet() {
    return new HashSet(keys);
  }
  public Collection values() {
    return values;
  }
  public Set entrySet() {
    Set set = new HashSet();
  //  Iterator it = keys.iterator();
  //  while(it.hasNext()) {
  //    Object k = it.next();
  //    Object v = values.get(values.indexOf(k));
  //    set.add(new Map.Entry(k, v));
  //  }
    return set;
  }
  // Test it:
  public static void main(String[] args) {
    AssocArray aa = new AssocArray();
    for(char c = 'a'; c <= 'z'; c++)
      aa.put(String.valueOf(c),
             String.valueOf(c)
             .toUpperCase());
    char[] ca = { 'a', 'e', 'i', 'o', 'u' };
    for(int i = 0; i < ca.length; i++)
      System.out.println("Uppercase: " +
             aa.get(String.valueOf(ca[i])));
  }
} ///:~