com.google.common.testing

Class CollectorTester<T,A,R>

java.lang.Object

com.google.common.testing.CollectorTester<T,A,R>

@Beta
 @GwtCompatible
public final class CollectorTester<T,A,R>
extends Object

Tester for Collector implementations.

Example usage:

 CollectorTester.of(Collectors.summingInt(Integer::parseInt))
     .expectCollects(3, "1", "2")
     .expectCollects(10, "1", "4", "3", "2")
     .expectCollects(5, "-3", "0", "8");
 

Since:

21.0

Author:

Louis Wasserman

Method Summary

Modifier and Type	Method and Description
CollectorTester<T,A,R>	expectCollects(R expectedResult, T... inputs) Verifies that the specified expected result is always produced by collecting the specified inputs, regardless of how the elements are divided.
static <T,A,R> CollectorTester<T,A,R>	of(java.util.stream.Collector<T,A,R> collector) Creates a CollectorTester for the specified Collector.
static <T,A,R> CollectorTester<T,A,R>	of(java.util.stream.Collector<T,A,R> collector, java.util.function.BiPredicate<? super R,? super R> equivalence) Creates a CollectorTester for the specified Collector.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

of

public static <T,A,R> CollectorTester<T,A,R> of(java.util.stream.Collector<T,A,R> collector)

Creates a CollectorTester for the specified Collector. The result of the Collector will be compared to the expected value using Object.equals.

of

public static <T,A,R> CollectorTester<T,A,R> of(java.util.stream.Collector<T,A,R> collector,
                                                java.util.function.BiPredicate<? super R,? super R> equivalence)

Creates a CollectorTester for the specified Collector. The result of the Collector will be compared to the expected value using the specified equivalence.

expectCollects

@SafeVarargs
public final CollectorTester<T,A,R> expectCollects(@Nullable
                                                                R expectedResult,
                                                                T... inputs)

Verifies that the specified expected result is always produced by collecting the specified inputs, regardless of how the elements are divided.