This was design basically as a research project to understand how java annotation works, and it worked out pretty well so i released it as a library, Google Guava already works very well for caches so i used it for that purpose and not some Weak/Soft Reference Map.

Next version would be the one with Java Instrumentation API, which is wayy more fun since you work with byte code and bytecode injection.

 @Cached(duration = 1, durationUnit = TimeUnit.HOURS, maximumSize = 10000L)
  public Map<String, Object> methodThatTakesTooMuchTime(String objId) throws InterruptedException {
    final Map<String, Object> stringObjectMap = Collections.synchronizedMap(new HashMap<String, Object>());
    stringObjectMap.put("name", "steve");
    stringObjectMap.put("data", new HashSet<String>() {{
      add("one");
      add("two");
    }});
    TimeUnit.SECONDS.sleep(3);
    return stringObjectMap;
  }