code: public void addOrModifyProperty(final String name, final String value) {
  		if (name == null) {
  			throw new SystemException("name parameter can not be null.");
  		}
  
  		if (name.length() < 1) {
  			throw new SystemException("name parameter can not be the empty String.");
  		}
  
  		if (value == null) {
  			throw new SystemException("value parameter can not be null.");
  		}
  
  		recordMessage(
  				"modifyProperties() - Adding property '" + name + "' with the value '" + value + "'.");
  
  		runtimeProperties.setProperty(name, value);
  
  		// clear the subContext cache, it's now invalid
  		subcontextCache.clear();
  	}
docs: {@inheritDoc}