code: protected void process(MatchCallback callback) {
          Yaml yaml = createYaml();
          for (Resource resource : this.resources) {
              boolean found = process(callback, yaml, resource);
              if (this.resolutionMethod == ResolutionMethod.FIRST_FOUND && found) {
                  return;
              }
          }
      }
docs: Provide an opportunity for subclasses to process the Yaml parsed from the
  supplied resources. Each resource is parsed in turn and the documents inside
  checked against the {@link #setDocumentMatchers(DocumentMatcher...)
  matchers}. If a document matches it is passed into the callback, along with
  its representation as Properties. Depending on the
  {@link #setResolutionMethod(ResolutionMethod)} not all of the documents will
  be parsed.
  
  @param callback a callback to delegate to once matching documents are found
  @see #createYaml()