com.github.npathai.hamcrestopt

Class OptionalMatchers

java.lang.Object

com.github.npathai.hamcrestopt.OptionalMatchers

public class OptionalMatchers
extends Object

Provides a set of Hamcrest matchers for java.util.Optional:

• isEmpty() - matches when the examined Optional contains no value.
• isPresent() - matches when the examined Optional contains a value.
• hasValue(Object) - matches when the examined Optional contains a value that is logically equal to the operand.
• hasValue(Matcher) - matches when the examined Optional contains a value that satisfies the specified matcher.

Author:

npathai

Method Summary

Modifier and Type	Method and Description
static <T> org.hamcrest.Matcher<Optional<T>>	hasValue(org.hamcrest.Matcher<? super T> matcher) Creates a matcher that matches when the examined Optional contains a value that satisfies the specified matcher.
static <T> org.hamcrest.Matcher<Optional<T>>	hasValue(T operand) Creates a matcher that matches when the examined Optional contains a value that is logically equal to the operand, as determined by calling the equals method on the value.
static org.hamcrest.Matcher<Optional<?>>	isEmpty() Creates a matcher that matches when the examined Optional contains no value.
static org.hamcrest.Matcher<Optional<?>>	isPresent() Creates a matcher that matches when the examined Optional contains a value.

Methods inherited from class java.lang.Object

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

Method Detail

isPresent

public static org.hamcrest.Matcher<Optional<?>> isPresent()

Creates a matcher that matches when the examined Optional contains a value.

     Optional<String> optionalObject = Optional.of("dummy value");
     assertThat(optionalObject, isPresent());
 

Returns:

a matcher that matches when the examined Optional contains a value.

isEmpty

public static org.hamcrest.Matcher<Optional<?>> isEmpty()

Creates a matcher that matches when the examined Optional contains no value.

     Optional<String> optionalObject = Optional.empty();
     assertThat(optionalObject, isEmpty());
 

Returns:

a matcher that matches when the examined Optional contains no value.

hasValue

public static <T> org.hamcrest.Matcher<Optional<T>> hasValue(T operand)

Creates a matcher that matches when the examined Optional contains a value that is logically equal to the operand, as determined by calling the equals method on the value.

     Optional<String> optionalInt = Optional.of("dummy value");
     assertThat(optionalInt, hasValue("dummy value"));
 

Type Parameters:

T - the class of the value.

Parameters:

operand - the object that any examined Optional value should equal

Returns:

a matcher that matches when the examined Optional contains a value that is logically equal to the operand.

hasValue

public static <T> org.hamcrest.Matcher<Optional<T>> hasValue(org.hamcrest.Matcher<? super T> matcher)

Creates a matcher that matches when the examined Optional contains a value that satisfies the specified matcher.

     Optional<String> optionalObject = Optional.of("dummy value");
     assertThat(optionalObject, hasValue(startsWith("dummy")));
 

Type Parameters:

T - the class of the value.

Parameters:

matcher - a matcher for the value of the examined Optional.

Returns:

a matcher that matches when the examined Optional contains a value that satisfies the specified matcher.