Module org.junit.jupiter.params
Package org.junit.jupiter.params.aggregator

Interface ArgumentsAggregator

@API(status=STABLE, since="5.7") public interface ArgumentsAggregator
ArgumentsAggregator is an abstraction for the aggregation of arguments provided by an ArgumentsProvider for a single invocation of a @ParameterizedTest method into a single object.

An ArgumentsAggregator is applied to a method parameter of a @ParameterizedTest method via the @AggregateWith annotation.

The result of the aggregation will be passed as an argument to the @ParameterizedTest method for the annotated parameter.

A common use case is the aggregation of multiple columns from a single line in a CSV file into a domain object such as a Person, Address, Order, etc.

Implementations must provide a no-args constructor and should not make any assumptions regarding when they are instantiated or how often they are called. Since instances may potentially be cached and called from different threads, they should be thread-safe and designed to be used as singletons.

Since:
5.2
See Also:
AggregateWith, ArgumentsAccessor, ParameterizedTest

  • Method Details

    • aggregateArguments

      Object aggregateArguments​(ArgumentsAccessor accessor, ParameterContext context) throws ArgumentsAggregationException
      Aggregate the arguments contained in the supplied accessor into a single object.
      Parameters:
      accessor - an ArgumentsAccessor containing the arguments to be aggregated; never null
      context - the parameter context where the aggregated result is to be supplied; never null
      Returns:
      the aggregated result; may be null but only if the target type is a reference type
      Throws:
      ArgumentsAggregationException - if an error occurs during the aggregation