public long getAmountOfPagesReadFromFile(String componentName) {
    if (componentName == null)
      return performanceCountersHolder.getAmountOfPagesReadFromFile();

    final PerformanceCountersHolder cHolder = countersByComponent.get(componentName);
    if (cHolder != null)
      return cHolder.getAmountOfPagesReadFromFile();

    return -1;
  }
public long getAmountOfPagesReadFromFile ( String componentName ) { if ( componentName == null ) return performanceCountersHolder . getAmountOfPagesReadFromFile ( ) ; final PerformanceCountersHolder cHolder = countersByComponent . get ( componentName ) ; if ( cHolder != null ) return cHolder . getAmountOfPagesReadFromFile ( ) ; return - 1 ; }
Amount of pages are read from file for component name of which is passed as method argument. If null value is passed then value
for whole system will be returned. If data for component with passed in name does not exist then <code>-1</code> will be
returned.

@param componentName Name of component data of which should be returned. Name is case sensitive.

@return Amount of pages are read from file.