code: public void setMatcher(final Matcher matcher) {
      Assert.notNull(matcher, "The Matcher used to match elements in the collection during the search operation by this Searcher ({0}) cannot be null!",
        getClass().getName());
      this.matcher = matcher;
    }
docs: Sets the Matcher used to match and find the desired element or elements in the collection.
  
  @param matcher the Matcher used to match and find the desired element or elements in the collection during
  the search operation.
  @throws NullPointerException if the Matcher reference to be used by this Searcher is null.
  @see #getMatcher()
  @see org.cp.elements.util.search.Matcher