code: public Map<CtClass, Set<CtMethod>> find(final CtMethod declaredMethod, final int level) {
  		return find(declaredMethod, level, new HashMap<CtClass, Set<CtMethod>>());
  	}
docs: Method to find all method calls done by a given {@link CtMethod}. The function can be parameterized using a level parameter:
  <p>
  When level < 0: Throw {@link IllegalArgumentException}.
  </p>
  <p>
  When level == 0: return the given method as only result wrapped into the result type.
  </p>
  <p>
  When level > 0: search recursive for method calls in subsequent methods called by the given method. Every subsearch will reduce the level by one. Stops
  when all subsearches are finished.
  </p>
  <br/>
  
  @param declaredMethod The method to search method call in
  @param level How deep should be the recursion level?
  
  @return A map with the surrounding class as key and the found methods as value, wrapped into a set.