Package org.assertj.core.api

Class AbstractOptionalAssert<SELF extends AbstractOptionalAssert<SELF,​VALUE>,​VALUE>

  • Type Parameters:
    SELF - the "self" type of this assertion class.
    VALUE - type of the value contained in the Optional.
    All Implemented Interfaces:
    Assert<SELF,​Optional<VALUE>>, Descriptable<SELF>, ExtensionPoints<SELF,​Optional<VALUE>>
    Direct Known Subclasses:
    OptionalAssert
    public abstract class AbstractOptionalAssert<SELF extends AbstractOptionalAssert<SELF,​VALUE>,​VALUE>
extends AbstractAssert<SELF,​Optional<VALUE>>
    Assertions for Optional.
    Author:
    Jean-Christophe Gay, Nicolai Parlog, Grzegorz Piwowarek

    • Field Detail

      • optionalValueComparisonStrategy

        private ComparisonStrategy optionalValueComparisonStrategy

    • Constructor Detail

      • AbstractOptionalAssert

        protected AbstractOptionalAssert​(Optional<VALUE> actual,
                                 Class<?> selfType)

    • Method Detail

      • isPresent

        public SELF isPresent()
        Verifies that there is a value present in the actual Optional.

        Assertion will pass : 

         assertThat(Optional.of("something")).isPresent();
        Assertion will fail : 
         assertThat(Optional.empty()).isPresent();
        Returns:
        this assertion object.

      • isNotEmpty

        public SELF isNotEmpty()
        Verifies that there is a value present in the actual Optional, it's an alias of isPresent().

        Assertion will pass : 

         assertThat(Optional.of("something")).isNotEmpty();
        Assertion will fail : 
         assertThat(Optional.empty()).isNotEmpty();
        Returns:
        this assertion object.

      • isEmpty

        public SELF isEmpty()
        Verifies that the actual Optional is empty.

        Assertion will pass : 

         assertThat(Optional.empty()).isEmpty();
        Assertion will fail : 
         assertThat(Optional.of("something")).isEmpty();
        Returns:
        this assertion object.

      • isNotPresent

        public SELF isNotPresent()
        Verifies that the actual Optional is empty (alias of isEmpty()).

        Assertion will pass : 

         assertThat(Optional.empty()).isNotPresent();
        Assertion will fail : 
         assertThat(Optional.of("something")).isNotPresent();
        Returns:
        this assertion object.

      • contains

        public SELF contains​(VALUE expectedValue)
        Verifies that the actual Optional contains the given value (alias of hasValue(Object)).

        Assertion will pass : 

         assertThat(Optional.of("something")).contains("something");
 assertThat(Optional.of(10)).contains(10);
        Assertion will fail : 
         assertThat(Optional.of("something")).contains("something else");
 assertThat(Optional.of(20)).contains(10);
        Parameters:
        expectedValue - the expected value inside the Optional.
        Returns:
        this assertion object.

      • hasValueSatisfying

        public SELF hasValueSatisfying​(Consumer<VALUE> requirement)
        Verifies that the actual Optional contains a value and gives this value to the given Consumer for further assertions. Should be used as a way of deeper asserting on the containing object, as further requirement(s) for the value.

        Assertions will pass : 

         // one requirement 
 assertThat(Optional.of(10)).hasValueSatisfying(i -> { assertThat(i).isGreaterThan(9); });

 // multiple requirements
 assertThat(Optional.of(someString)).hasValueSatisfying(s -> {
   assertThat(s).isEqualTo("something");
   assertThat(s).startsWith("some");
   assertThat(s).endsWith("thing");
 });
        Assertions will fail : 
         assertThat(Optional.of("something")).hasValueSatisfying(s -> {
     assertThat(s).isEqualTo("something else");
   });

 // fail because optional is empty, there is no value to perform assertion on  
 assertThat(Optional.empty()).hasValueSatisfying(o -> {});
        Parameters:
        requirement - to further assert on the object contained inside the Optional.
        Returns:
        this assertion object.

      • hasValueSatisfying

        public SELF hasValueSatisfying​(Condition<? super VALUE> condition)
        Verifies that the actual Optional contains a value which satisfies the given Condition.

        Examples: 

         Condition<TolkienCharacter> isAnElf = new Condition<>(character -> character.getRace() == ELF, "an elf"); 
 
 TolkienCharacter legolas = new TolkienCharacter("Legolas", 1000, ELF);
 TolkienCharacter frodo = new TolkienCharacter("Frodo", 33, HOBBIT);
 
 // assertion succeeds
 assertThat(Optional.of(legolas)).hasValueSatisfying(isAnElf);
                                     
 // assertion fails
 assertThat(Optional.of(frodo)).hasValueSatisfying(isAnElf);
        Parameters:
        condition - the given condition.
        Returns:
        this assertion object.
        Throws:
        AssertionError - if the actual Optional is null or empty.
        NullPointerException - if the given condition is null.
        AssertionError - if the actual value does not satisfy the given condition.
        Since:
        3.6.0

      • hasValue

        public SELF hasValue​(VALUE expectedValue)
        Verifies that the actual Optional contains the given value (alias of contains(Object)).

        Assertion will pass : 

         assertThat(Optional.of("something")).hasValue("something");
 assertThat(Optional.of(10)).contains(10);
        Assertion will fail : 
         assertThat(Optional.of("something")).hasValue("something else");
 assertThat(Optional.of(20)).contains(10);
        Parameters:
        expectedValue - the expected value inside the Optional.
        Returns:
        this assertion object.

      • containsInstanceOf

        public SELF containsInstanceOf​(Class<?> clazz)
        Verifies that the actual Optional contains a value that is an instance of the argument.

        Assertions will pass: 

         assertThat(Optional.of("something")).containsInstanceOf(String.class)
                                     .containsInstanceOf(Object.class);

 assertThat(Optional.of(10)).containsInstanceOf(Integer.class);
        Assertion will fail: 
         assertThat(Optional.of("something")).containsInstanceOf(Integer.class);
        Parameters:
        clazz - the expected class of the value inside the Optional.
        Returns:
        this assertion object.

      • usingFieldByFieldValueComparator

        public SELF usingFieldByFieldValueComparator()
        Use field/property by field/property comparison (including inherited fields/properties) instead of relying on actual type A equals method to compare the Optional value's object for incoming assertion checks. Private fields are included but this can be disabled using Assertions.setAllowExtractingPrivateFields(boolean).

        This can be handy if equals method of the Optional value's object to compare does not suit you.

        Note that the comparison is not recursive, if one of the fields/properties is an Object, it will be compared to the other field/property using its equals method.

        Example: 

         TolkienCharacter frodo = new TolkienCharacter("Frodo", 33, HOBBIT);
 TolkienCharacter frodoClone = new TolkienCharacter("Frodo", 33, HOBBIT);

 // Fail if equals has not been overridden in TolkienCharacter as equals default implementation only compares references
 assertThat(Optional.of(frodo)).contains(frodoClone);

 // frodo and frodoClone are equals when doing a field by field comparison.
 assertThat(Optional.of(frodo)).usingFieldByFieldValueComparator().contains(frodoClone);
        Returns:
        this assertion object.

      • usingValueComparator

        public SELF usingValueComparator​(Comparator<? super VALUE> customComparator)
        Use given custom comparator instead of relying on actual type A equals method to compare the Optional value's object for incoming assertion checks.

        Custom comparator is bound to assertion instance, meaning that if a new assertion is created, it will use default comparison strategy.

        Examples : 

         TolkienCharacter frodo = new TolkienCharacter("Frodo", 33, HOBBIT);
 TolkienCharacter frodoClone = new TolkienCharacter("Frodo", 33, HOBBIT);

 // Fail if equals has not been overridden in TolkienCharacter as equals default implementation only compares references
 assertThat(Optional.of(frodo)).contains(frodoClone);

 // frodo and frodoClone are equals when doing a field by field comparison.
 assertThat(Optional.of(frodo)).usingValueComparator(new FieldByFieldComparator()).contains(frodoClone);
        Parameters:
        customComparator - the comparator to use for incoming assertion checks.
        Returns:
        this assertion object.
        Throws:
        NullPointerException - if the given comparator is null.

      • usingDefaultValueComparator

        public SELF usingDefaultValueComparator()
        Revert to standard comparison for incoming assertion Optional value checks.

        This method should be used to disable a custom comparison strategy set by calling usingValueComparator(Comparator).

        Returns:
        this assertion object.

      • containsSame

        public SELF containsSame​(VALUE expectedValue)
        Verifies that the actual Optional contains the instance given as an argument (i.e. it must be the same instance).

        Assertion will pass : 

         String someString = "something";
 assertThat(Optional.of(someString)).containsSame(someString);

 // Java will create the same 'Integer' instance when boxing small ints
 assertThat(Optional.of(10)).containsSame(10);
        Assertion will fail : 
         // not even equal:
 assertThat(Optional.of("something")).containsSame("something else");
 assertThat(Optional.of(20)).containsSame(10);

 // equal but not the same: 
 assertThat(Optional.of(new String("something"))).containsSame(new String("something"));
 assertThat(Optional.of(new Integer(10))).containsSame(new Integer(10));
        Parameters:
        expectedValue - the expected value inside the Optional.
        Returns:
        this assertion object.

      • flatMap

        public <U> AbstractOptionalAssert<?,​U> flatMap​(Function<? super VALUE,​Optional<U>> mapper)
        Call flatMap on the Optional under test, assertions chained afterwards are performed on the Optional resulting from the flatMap call.

        Examples: 

         Function<String, Optional<String>> UPPER_CASE_OPTIONAL_STRING = 
       s -> s == null ? Optional.empty() : Optional.of(s.toUpperCase());
 
 // assertions succeed
 assertThat(Optional.of("something")).contains("something")
                                     .flatMap(UPPER_CASE_OPTIONAL_STRING)
                                     .contains("SOMETHING");
                                     
 assertThat(Optional.<String>empty()).flatMap(UPPER_CASE_OPTIONAL_STRING)
                                     .isEmpty();
                                     
 assertThat(Optional.<String>ofNullable(null)).flatMap(UPPER_CASE_OPTIONAL_STRING)
                                              .isEmpty();
                                     
 // assertion fails
 assertThat(Optional.of("something")).flatMap(UPPER_CASE_OPTIONAL_STRING)
                                     .contains("something");
        Type Parameters:
        U - the type wrapped in the Optional after the flatMap operation.
        Parameters:
        mapper - the Function to use in the flatMap operation.
        Returns:
        a new AbstractOptionalAssert for assertions chaining on the flatMap of the Optional.
        Throws:
        AssertionError - if the actual Optional is null.
        Since:
        3.6.0

      • map

        public <U> AbstractOptionalAssert<?,​U> map​(Function<? super VALUE,​? extends U> mapper)
        Call map on the Optional under test, assertions chained afterwards are performed on the Optional resulting from the map call.

        Examples: 

         // assertions succeed 
 assertThat(Optional.<String>empty()).map(String::length)
                                     .isEmpty();
 
 assertThat(Optional.of("42")).contains("42")
                              .map(String::length)
                              .contains(2);
                              
 // assertion fails
 assertThat(Optional.of("42")).map(String::length)
                              .contains(3);
        Type Parameters:
        U - the type wrapped in the Optional after the map operation.
        Parameters:
        mapper - the Function to use in the map operation.
        Returns:
        a new AbstractOptionalAssert for assertions chaining on the map of the Optional.
        Throws:
        AssertionError - if the actual Optional is null.
        Since:
        3.6.0

      • get

        public AbstractObjectAssert<?,​VALUE> get()
        Verifies that the actual Optional is not null and not empty and returns an Object assertion that allows chaining (object) assertions on the optional value.

        Note that it is only possible to return Object assertions after calling this method due to java generics limitations.

        Example: 

         TolkienCharacter frodo = new TolkienCharacter("Frodo", 33, HOBBIT);
 TolkienCharacter sam = new TolkienCharacter("Sam", 38, null);

 // assertion succeeds since all frodo's fields are set
 assertThat(Optional.of(frodo)).get().hasNoNullFields();

 // assertion does not succeed because sam does not have its race set
 assertThat(Optional.of(sam)).get().hasNoNullFields();
        Returns:
        a new AbstractObjectAssert for assertions chaining on the value of the Optional.
        Throws:
        AssertionError - if the actual Optional is null.
        AssertionError - if the actual Optional is empty.
        Since:
        3.9.0

      • checkNotNull

        private void checkNotNull​(Object expectedValue)

      • assertValueIsPresent

        private void assertValueIsPresent()