code: public static RestartStrategy createRestartStrategy(RestartStrategies.RestartStrategyConfiguration restartStrategyConfiguration) {
  		if (restartStrategyConfiguration instanceof RestartStrategies.NoRestartStrategyConfiguration) {
  			return new NoRestartStrategy();
  		} else if (restartStrategyConfiguration instanceof RestartStrategies.FixedDelayRestartStrategyConfiguration) {
  			RestartStrategies.FixedDelayRestartStrategyConfiguration fixedDelayConfig =
  				(RestartStrategies.FixedDelayRestartStrategyConfiguration) restartStrategyConfiguration;
  
  			return new FixedDelayRestartStrategy(
  				fixedDelayConfig.getRestartAttempts(),
  				fixedDelayConfig.getDelayBetweenAttemptsInterval().toMilliseconds());
  		} else if (restartStrategyConfiguration instanceof RestartStrategies.FailureRateRestartStrategyConfiguration) {
  			RestartStrategies.FailureRateRestartStrategyConfiguration config =
  					(RestartStrategies.FailureRateRestartStrategyConfiguration) restartStrategyConfiguration;
  			return new FailureRateRestartStrategy(
  					config.getMaxFailureRate(),
  					config.getFailureInterval(),
  					config.getDelayBetweenAttemptsInterval()
  			);
  		} else if (restartStrategyConfiguration instanceof RestartStrategies.FallbackRestartStrategyConfiguration) {
  			return null;
  		} else {
  			throw new IllegalArgumentException("Unknown restart strategy configuration " +
  				restartStrategyConfiguration + ".");
  		}
  	}
docs: Creates a {@link RestartStrategy} instance from the given {@link org.apache.flink.api.common.restartstrategy.RestartStrategies.RestartStrategyConfiguration}.
  
  @param restartStrategyConfiguration Restart strategy configuration which specifies which
  restart strategy to instantiate
  @return RestartStrategy instance