code: public FunctionInfo getFunction(String name) {
  
          if (functions == null || functions.length == 0) {
              System.err.println("No functions");
              return null;
          }
  
          for (int i=0; i < functions.length; i++) {
              if (functions[i].getName().equals(name)) {
                  return functions[i];
              }
          }
          return null;
      }
docs: Get the FunctionInfo for a given function name, looking through all the
  functions in this tag library.
  
  @param name The name (no prefix) of the function
  @return the FunctionInfo for the function with the given name, or null
  if no such function exists
  @since JSP 2.0