SELF - the "self" type of this assertion class. Please read "Emulating 'self types' using Java Generics to simplify fluent API implementation"
for more details.ACTUAL - the type of the "actual" value.public abstract class AbstractObjectAssert<SELF extends AbstractObjectAssert<SELF,ACTUAL>,ACTUAL> extends AbstractAssert<SELF,ACTUAL>
Objects.actual, info, myself, objects, throwUnsupportedExceptionOnEquals| Constructor and Description |
|---|
AbstractObjectAssert(ACTUAL actual,
Class<?> selfType) |
| Modifier and Type | Method and Description |
|---|---|
SELF |
as(Description description)
Sets the description of the assertion that is going to be called after.
|
SELF |
as(String description,
Object... args)
Sets the description of the assertion that is going to be called after.
|
<T> SELF |
doesNotReturn(T expected,
Function<ACTUAL,T> from)
Verifies that the object under test does not return the given expected value from the given
Function,
a typical usage is to pass a method reference to assert object's property. |
AbstractListAssert<?,List<?>,Object,ObjectAssert<Object>> |
extracting(Function<? super ACTUAL,?>... extractors)
Uses the given
Functions to extract the values from the object under test into a list, this new list becoming
the object under test. |
<T> AbstractObjectAssert<?,T> |
extracting(Function<? super ACTUAL,T> extractor)
Uses the given
Function to extract a value from the object under test, the extracted value becoming the new object under test. |
<T,ASSERT extends AbstractAssert<?,?>> |
extracting(Function<? super ACTUAL,T> extractor,
InstanceOfAssertFactory<?,ASSERT> assertFactory)
Uses the given
Function to extract a value from the object under test, the extracted value becoming the new object under test. |
AbstractListAssert<?,List<?>,Object,ObjectAssert<Object>> |
extracting(String... propertiesOrFields)
Extracts the values of given fields/properties from the object under test into a list, this new list becoming
the object under test.
|
AbstractObjectAssert<?,?> |
extracting(String propertyOrField)
Extracts the value of given field/property from the object under test, the extracted value becoming the new object under test.
|
<ASSERT extends AbstractAssert<?,?>> |
extracting(String propertyOrField,
InstanceOfAssertFactory<?,ASSERT> assertFactory)
Extracts the value of given field/property from the object under test, the extracted value becoming the new object under test.
|
protected AbstractListAssert<?,List<?>,Object,ObjectAssert<Object>> |
extractingForProxy(Function<? super ACTUAL,?>[] extractors) |
protected TypeComparators |
getComparatorsByType() |
SELF |
hasAllNullFieldsOrProperties()
Asserts that the actual object has only null fields or properties.
|
SELF |
hasAllNullFieldsOrPropertiesExcept(String... propertiesOrFieldsToIgnore)
Asserts that the actual object has only null fields or properties except for the given ones
(inherited ones are taken into account).
|
SELF |
hasFieldOrProperty(String name)
Asserts that the actual object has the specified field or property.
|
SELF |
hasFieldOrPropertyWithValue(String name,
Object value)
Asserts that the actual object has the specified field or property with the given value.
|
SELF |
hasNoNullFieldsOrProperties()
Asserts that the actual object has no null fields or properties (inherited ones are taken into account).
|
SELF |
hasNoNullFieldsOrPropertiesExcept(String... propertiesOrFieldsToIgnore)
Asserts that the actual object has no null fields or properties except for the given ones
(inherited ones are taken into account).
|
SELF |
hasOnlyFields(String... expectedFieldNames)
Asserts that the actual object has only the specified fields and nothing else.
|
SELF |
isEqualToComparingFieldByField(Object other)
Deprecated.
Use the recursive comparison by calling
usingRecursiveComparison().
This method is deprecated because it only compares the first level of fields while the recursive comparison traverses all fields recursively (only stopping at java types). For example suppose actual and expected are of type A which has the following structure: isEqualToComparingFieldByField will compare actual and expected A.b and A.i fields but not B fields
(it calls B equals method instead comparing B fields).The recursive comparison on the other hand will introspect B fields and then C fields and will compare actual and expected respective fields values, that is: A.i, A.B.s, A.B.C.s and A.B.C.d.
Concretely instead of writing:
Asserts that actual object is equal to the given object based on a property/field by property/field comparison (including
inherited ones). This can be handy if
Note that comparison is not recursive, if one of the field is an Object, it will be compared to the other
field using its If an object has a field and a property with the same name, the property value will be used over the field.
Private fields are used in comparison but this can be disabled using
The objects to compare can be of different types but the properties/fields used in comparison must exist in both, for example if actual object has a name String field, it is expected the other object to also have one. Example: |
SELF |
isEqualToComparingFieldByFieldRecursively(Object other)
Deprecated.
Prefer calling
usingRecursiveComparison() for comparing objects field by field as it offers more flexibility, better reporting and an easier to use API.
Asserts that the object under test (actual) is equal to the given object based on a recursive property/field by property/field comparison (including
inherited ones). This can be useful if actual's equals implementation does not suit you.
The recursive property/field comparison is not applied on fields having a custom equals implementation, i.e.
the overridden equals method will be used instead of a field by field comparison.
The recursive comparison handles cycles. By default
You can specify a custom comparator per (nested) fields or type with respectively The objects to compare can be of different types but must have the same properties/fields. For example if actual object has a name String field, it is expected the other object to also have one. If an object has a field and a property with the same name, the property value will be used over the field. Example: |
SELF |
isEqualToComparingOnlyGivenFields(Object other,
String... propertiesOrFieldsUsedInComparison)
Deprecated.
Use the recursive comparison by calling
usingRecursiveComparison() and specify the fields to ignore.
Warning: the recursive comparison does not provide a strictly equivalent feature, instead it provides several ways to ignore
fields in the comparison This method is deprecated because it only compares the first level of fields while the recursive comparison traverses all fields recursively (only stopping at java types). For example suppose actual and expected are of type A which has the following structure: isEqualToComparingOnlyGivenFields will compare actual and expected A.b and A.i fields but not B fields
(it calls B equals method instead comparing B fields).The recursive comparison on the other hand will introspect B fields and then C fields and will compare actual and expected respective fields values, that is: A.i, A.B.s, A.B.C.s and A.B.C.d.
Assuming actual has 4 fields f1, f2, f3, f4, instead of writing:
Asserts that the actual object is equal to the given one using a property/field by property/field comparison on the given properties/fields only
(fields can be inherited fields or nested fields). This can be handy if
Note that comparison is not recursive, if one of the field is an Object, it will be compared to the other
field using its If an object has a field and a property with the same name, the property value will be used over the field.
Private fields are used in comparison but this can be disabled using
The objects to compare can be of different types but the properties/fields used in comparison must exist in both, for example if actual object has a name String field, it is expected the other object to also have one. Example: |
SELF |
isEqualToIgnoringGivenFields(Object other,
String... propertiesOrFieldsToIgnore)
Deprecated.
Use the recursive comparison by calling
usingRecursiveComparison() and chain with
ignoringFields(String...).
This method is deprecated because it only compares the first level of fields while the recursive comparison traverses all fields recursively (only stopping at java types). For example suppose actual and expected are of type A which has the following structure: isEqualToIgnoringGivenFields will compare actual and expected A.b and A.i fields but not B fields
(it calls B equals method instead comparing B fields).The recursive comparison on the other hand will introspect B fields and then C fields and will compare actual and expected respective fields values, that is: A.i, A.B.s, A.B.C.s and A.B.C.d.
Concretely instead of writing:
Note that the recursive comparison also allows to ignore fields
Asserts that the actual object is equal to the given one by comparing their properties/fields except for the given ones
(inherited ones are taken into account). This can be handy if
Note that comparison is not recursive, if one of the property/field is an Object, it will be compared to the other
field using its If an object has a field and a property with the same name, the property value will be used over the field.
Private fields are used in comparison but this can be disabled using
The objects to compare can be of different types but the properties/fields used in comparison must exist in both, for example if actual object has a name String field, it is expected the other object to also have one. Example: |
SELF |
isEqualToIgnoringNullFields(Object other)
Deprecated.
Use the recursive comparison by calling
usingRecursiveComparison() and chain with
ignoringExpectedNullFields().
This method is deprecated because it only compares the first level of fields while the recursive comparison traverses all fields recursively (only stopping at java types). For example suppose actual and expected are of type A which has the following structure: isEqualToIgnoringNullFields will compare actual and expected A.b and A.i fields but not B fields
(it calls B equals method instead comparing B fields).The recursive comparison on the other hand will introspect B fields and then C fields and will compare actual and expected respective fields values, that is: A.i, A.B.s, A.B.C.s and A.B.C.d.
Concretely instead of writing:
Note that the recursive comparison also allows to ignore actual's null fields with
Asserts that the actual object is equal to the given one by comparing actual's properties/fields with other's not null properties/fields only (including inherited ones). It means that if an actual field is not null and the corresponding field in other is null, this field will be ignored in comparison, but the opposite will make assertion fail (null field in actual, not null in other) as the field is used in the performed comparison and the values differ.
Note that comparison is not recursive, if one of the field is an Object, it will be compared to the other
field using its If an object has a field and a property with the same name, the property value will be used over the field.
Private fields are used in comparison but this can be disabled using
The objects to compare can be of different types but the properties/fields used in comparison must exist in both, for example if actual object has a name String field, it is expected other object to also have one. Example: |
protected <T> AbstractObjectAssert<?,T> |
newObjectAssert(T objectUnderTest) |
<T> SELF |
returns(T expected,
Function<ACTUAL,T> from)
Verifies that the object under test returns the given expected value from the given
Function,
a typical usage is to pass a method reference to assert object's property. |
<T> SELF |
usingComparatorForFields(Comparator<T> comparator,
String... propertiesOrFields)
Allows to set a specific comparator to compare properties or fields with the given names.
|
<T> SELF |
usingComparatorForType(Comparator<? super T> comparator,
Class<T> type)
Allows to set a specific comparator to compare properties or fields with the given type.
|
RecursiveComparisonAssert<?> |
usingRecursiveComparison()
Enable using a recursive field by field comparison strategy when calling the chained
isEqualTo assertion. |
RecursiveComparisonAssert<?> |
usingRecursiveComparison(RecursiveComparisonConfiguration recursiveComparisonConfiguration)
Same as
usingRecursiveComparison() but allows to specify your own RecursiveComparisonConfiguration. |
areEqual, asInstanceOf, asList, assertionError, asString, describedAs, descriptionText, doesNotHave, doesNotHaveSameClassAs, doesNotHaveSameHashCodeAs, doesNotHaveToString, equals, extracting, extracting, failure, failureWithActualExpected, failWithActualExpectedAndMessage, failWithMessage, getWritableAssertionInfo, has, hashCode, hasSameClassAs, hasSameHashCodeAs, hasToString, inBinary, inHexadecimal, is, isElementOfCustomAssert, isEqualTo, isExactlyInstanceOf, isIn, isIn, isInstanceOf, isInstanceOfAny, isInstanceOfSatisfying, isNot, isNotEqualTo, isNotExactlyInstanceOf, isNotIn, isNotIn, isNotInstanceOf, isNotInstanceOfAny, isNotNull, isNotOfAnyClassIn, isNotSameAs, isNull, isOfAnyClassIn, isSameAs, matches, matches, newListAssertInstance, overridingErrorMessage, overridingErrorMessage, satisfies, satisfies, satisfies, satisfiesAnyOf, satisfiesAnyOf, satisfiesAnyOfForProxy, satisfiesForProxy, setCustomRepresentation, setDescriptionConsumer, setPrintAssertionsDescription, throwAssertionError, usingComparator, usingComparator, usingDefaultComparator, withFailMessage, withFailMessage, withRepresentation, withThreadDumpOnErrorclone, finalize, getClass, notify, notifyAll, toString, wait, wait, waitas, describedAspublic SELF as(Description description)
DescriptableYou must set it before calling the assertion otherwise it is ignored as the failing assertion breaks the chained call by throwing an AssertionError.
This overloaded version of "describedAs" offers more flexibility than the one taking a String by allowing
users to pass their own implementation of a description. For example, a description that creates its value lazily,
only when an assertion failure occurs.
description - the new description to set.this object.Descriptable.describedAs(Description)public SELF as(String description, Object... args)
DescriptableYou must set it before calling the assertion otherwise it is ignored as the failing assertion breaks the chained call by throwing an AssertionError.
The description follows String.format(String, Object...) syntax.
Example :
try {
// set an incorrect age to Mr Frodo which is really 33 years old.
frodo.setAge(50);
// specify a test description (call as() before the assertion !), it supports String format syntax.
assertThat(frodo.getAge()).as("check %s's age", frodo.getName()).isEqualTo(33);
} catch (AssertionError e) {
assertThat(e).hasMessage("[check Frodo's age]\n
expected: 33\n
but was: 50");
}description - the new description to set.args - optional parameter if description is a format String.this object.Descriptable.describedAs(String, Object...)@Deprecated public SELF isEqualToIgnoringNullFields(Object other)
usingRecursiveComparison() and chain with
ignoringExpectedNullFields().
This method is deprecated because it only compares the first level of fields while the recursive comparison traverses all fields recursively (only stopping at java types).
For example suppose actual and expected are of type A which has the following structure:
A
|— B b
| |— String s
| |— C c
| |— String s
| |— Date d
|— int iisEqualToIgnoringNullFields will compare actual and expected A.b and A.i fields but not B fields
(it calls B equals method instead comparing B fields).A.i, A.B.s, A.B.C.s and A.B.C.d.
Concretely instead of writing:
assertThat(actual).isEqualToIgnoringNullFields(expected); assertThat(actual).usingRecursiveComparison()
.ignoringExpectedNullFields()
.isEqualTo(expected);
Note that the recursive comparison also allows to ignore actual's null fields with
ignoringActualNullFields().
Original javadoc
Asserts that the actual object is equal to the given one by comparing actual's properties/fields with other's not null properties/fields only (including inherited ones).
It means that if an actual field is not null and the corresponding field in other is null, this field will be ignored in comparison, but the opposite will make assertion fail (null field in actual, not null in other) as the field is used in the performed comparison and the values differ.
Note that comparison is not recursive, if one of the field is an Object, it will be compared to the other
field using its equals method.
If an object has a field and a property with the same name, the property value will be used over the field.
Private fields are used in comparison but this can be disabled using
Assertions.setAllowComparingPrivateFields(boolean), if disabled only accessible fields values are
compared, accessible fields include directly accessible fields (e.g. public) or fields with an accessible getter.
The objects to compare can be of different types but the properties/fields used in comparison must exist in both, for example if actual object has a name String field, it is expected other object to also have one.
Example:
TolkienCharacter frodo = new TolkienCharacter("Frodo", 33, HOBBIT);
TolkienCharacter mysteriousHobbit = new TolkienCharacter(null, 33, HOBBIT);
// Null fields in other/expected object are ignored, the mysteriousHobbit has null name thus name is ignored
assertThat(frodo).isEqualToIgnoringNullFields(mysteriousHobbit); // OK
// ... but this is not reversible !
assertThat(mysteriousHobbit).isEqualToIgnoringNullFields(frodo); // FAILother - the object to compare actual to.this assertion object.NullPointerException - if the actual or other object is null.AssertionError - if the actual and the given object are not lenient equals.IntrospectionError - if one of actual's field to compare can't be found in the other object.@Deprecated public SELF isEqualToComparingOnlyGivenFields(Object other, String... propertiesOrFieldsUsedInComparison)
usingRecursiveComparison() and specify the fields to ignore.
Warning: the recursive comparison does not provide a strictly equivalent feature, instead it provides several ways to ignore
fields in the comparison by specifying fields to ignore, or
fields by type or
fields matching regexes. The idea being that it is best
to compare as many fields as possible and only ignore the ones that are not relevant (for example generated ids).
This method is deprecated because it only compares the first level of fields while the recursive comparison traverses all fields recursively (only stopping at java types).
For example suppose actual and expected are of type A which has the following structure:
A
|— B b
| |— String s
| |— C c
| |— String s
| |— Date d
|— int iisEqualToComparingOnlyGivenFields will compare actual and expected A.b and A.i fields but not B fields
(it calls B equals method instead comparing B fields).A.i, A.B.s, A.B.C.s and A.B.C.d.
Assuming actual has 4 fields f1, f2, f3, f4, instead of writing:
assertThat(actual).isEqualToComparingOnlyGivenFields(expected, f1, f2); assertThat(actual).usingRecursiveComparison()
.ignoringFields(f3, f4)
.isEqualTo(expected);
Asserts that the actual object is equal to the given one using a property/field by property/field comparison on the given properties/fields only
(fields can be inherited fields or nested fields). This can be handy if equals implementation of objects to compare does not suit you.
Note that comparison is not recursive, if one of the field is an Object, it will be compared to the other
field using its equals method.
If an object has a field and a property with the same name, the property value will be used over the field.
Private fields are used in comparison but this can be disabled using
Assertions.setAllowComparingPrivateFields(boolean), if disabled only accessible fields values are
compared, accessible fields include directly accessible fields (e.g. public) or fields with an accessible getter.
The objects to compare can be of different types but the properties/fields used in comparison must exist in both, for example if actual object has a name String field, it is expected the other object to also have one.
Example:
TolkienCharacter frodo = new TolkienCharacter("Frodo", 33, HOBBIT);
TolkienCharacter sam = new TolkienCharacter("Sam", 38, HOBBIT);
// frodo and sam both are hobbits, so they are equals when comparing only race
assertThat(frodo).isEqualToComparingOnlyGivenFields(sam, "race"); // OK
// they are also equals when comparing only race name (nested field).
assertThat(frodo).isEqualToComparingOnlyGivenFields(sam, "race.name"); // OK
// ... but not when comparing both name and race
assertThat(frodo).isEqualToComparingOnlyGivenFields(sam, "name", "race"); // FAILother - the object to compare actual to.propertiesOrFieldsUsedInComparison - properties/fields used in comparison.this assertion object.NullPointerException - if the actual or other is null.AssertionError - if the actual and the given objects are not equals property/field by property/field on given fields.IntrospectionError - if one of actual's property/field to compare can't be found in the other object.IntrospectionError - if a property/field does not exist in actual.@Deprecated public SELF isEqualToIgnoringGivenFields(Object other, String... propertiesOrFieldsToIgnore)
usingRecursiveComparison() and chain with
ignoringFields(String...).
This method is deprecated because it only compares the first level of fields while the recursive comparison traverses all fields recursively (only stopping at java types).
For example suppose actual and expected are of type A which has the following structure:
A
|— B b
| |— String s
| |— C c
| |— String s
| |— Date d
|— int iisEqualToIgnoringGivenFields will compare actual and expected A.b and A.i fields but not B fields
(it calls B equals method instead comparing B fields).A.i, A.B.s, A.B.C.s and A.B.C.d.
Concretely instead of writing:
assertThat(actual).isEqualToIgnoringGivenFields(expected, "i", "b.s"); assertThat(actual).usingRecursiveComparison()
.ignoringFields("i", "b.s")
.isEqualTo(expected);
Note that the recursive comparison also allows to ignore fields
by type or
matching regexes.
Original javadoc
Asserts that the actual object is equal to the given one by comparing their properties/fields except for the given ones
(inherited ones are taken into account). This can be handy if equals implementation of objects to compare does not suit you.
Note that comparison is not recursive, if one of the property/field is an Object, it will be compared to the other
field using its equals method.
If an object has a field and a property with the same name, the property value will be used over the field.
Private fields are used in comparison but this can be disabled using
Assertions.setAllowComparingPrivateFields(boolean), if disabled only accessible fields values are
compared, accessible fields include directly accessible fields (e.g. public) or fields with an accessible getter.
The objects to compare can be of different types but the properties/fields used in comparison must exist in both, for example if actual object has a name String field, it is expected the other object to also have one.
Example:
TolkienCharacter frodo = new TolkienCharacter("Frodo", 33, HOBBIT);
TolkienCharacter sam = new TolkienCharacter("Sam", 38, HOBBIT);
// frodo and sam are equals when ignoring name and age since the only remaining field is race which they share as HOBBIT.
assertThat(frodo).isEqualToIgnoringGivenFields(sam, "name", "age"); // OK
// ... but they are not equals if only age is ignored as their names differ.
assertThat(frodo).isEqualToIgnoringGivenFields(sam, "age"); // FAILother - the object to compare actual to.propertiesOrFieldsToIgnore - ignored properties/fields to ignore in comparison.this assertion object.NullPointerException - if the actual or given object is null.AssertionError - if the actual and the given objects are not equals property/field by property/field after ignoring given fields.IntrospectionError - if one of actual's property/field to compare can't be found in the other object.public SELF hasNoNullFieldsOrProperties()
If an object has a field and a property with the same name, the property value will be used over the field.
Private fields are checked, but this can be disabled using Assertions.setAllowComparingPrivateFields(boolean),
if disabled only accessible fields values are
checked, accessible fields include directly accessible fields (e.g. public) or fields with an accessible getter.
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(frodo).hasNoNullFieldsOrProperties();
// assertion fails because sam does not have its race set
assertThat(sam).hasNoNullFieldsOrProperties();this assertion object.AssertionError - if the actual object is null.AssertionError - if some fields or properties of the actual object are null.public SELF hasAllNullFieldsOrProperties()
If an object has a field and a property with the same name, the property value will be used over the field.
Private fields are checked, but this can be disable using Assertions.setAllowComparingPrivateFields(boolean),
if disable only accessible fields values are checked,
accessible fields include directly accessible fields (e.g. public) or fields with an accessible getter.
Example:
TolkienCharacter frodo = new TolkienCharacter(null, null, null);
TolkienCharacter sam = new TolkienCharacter("sam", null, null);
// assertion succeeds since all frodo's fields are null
assertThat(frodo).hasAllNullFieldsOrProperties();
// assertion fails because sam has its name set
assertThat(sam).hasAllNullFieldsOrProperties();this assertion object.AssertionError - if the actual object is null.AssertionError - if some field or properties of the actual object are not null.public SELF hasNoNullFieldsOrPropertiesExcept(String... propertiesOrFieldsToIgnore)
If an object has a field and a property with the same name, the property value will be used over the field.
Private fields are checked, but this can be disabled using Assertions.setAllowComparingPrivateFields(boolean),
if disabled only accessible fields values are checked,
accessible fields include directly accessible fields (e.g. public) or fields with an accessible getter.
Example:
TolkienCharacter frodo = new TolkienCharacter("Frodo", 33, null);
// assertion succeeds since frodo has only null field is race
assertThat(frodo).hasNoNullFieldsOrPropertiesExcept("race");
// ... but if we require the race field, the assertion fails
assertThat(frodo).hasNoNullFieldsOrPropertiesExcept("name", "age");propertiesOrFieldsToIgnore - properties/fields that won't be checked for null.this assertion object.AssertionError - if the actual object is null.AssertionError - if some (non ignored) fields or properties of the actual object are null.public SELF hasAllNullFieldsOrPropertiesExcept(String... propertiesOrFieldsToIgnore)
If an object has a field and a property with the same name, the property value will be user over the field.
Private fields are checked, but this can be disable using Assertions.setAllowComparingPrivateFields(boolean),
if disabled only accessible fields values are checked,
accessible fields include directly accessible fields (e.g. public) or fields with an accessible getter.
Example:
TolkienCharacter frodo = new TolkienCharacter("Frodo", null, null);
// assertion succeeds since frodo has only non null field is name
assertThat(frodo).hasAllNullFieldsOrPropertiesExcept("name");
// ... but if we specify any field other than name, the assertion fails
assertThat(frodo).hasAllNullFieldsOrPropertiesExcept("race");propertiesOrFieldsToIgnore - properties/fields that won't be checked for not being null.this assertion object.AssertionError - if the actual object is null.AssertionError - if some (non ignored) fields or properties of the actual object are not null.@Deprecated public SELF isEqualToComparingFieldByField(Object other)
usingRecursiveComparison().
This method is deprecated because it only compares the first level of fields while the recursive comparison traverses all fields recursively (only stopping at java types).
For example suppose actual and expected are of type A which has the following structure:
A
|— B b
| |— String s
| |— C c
| |— String s
| |— Date d
|— int i isEqualToComparingFieldByField will compare actual and expected A.b and A.i fields but not B fields
(it calls B equals method instead comparing B fields).A.i, A.B.s, A.B.C.s and A.B.C.d.
Concretely instead of writing:
assertThat(actual).isEqualToComparingFieldByField(expected); assertThat(actual).usingRecursiveComparison()
.isEqualTo(expected);
Asserts that actual object is equal to the given object based on a property/field by property/field comparison (including
inherited ones). This can be handy if equals implementation of objects to compare does not suit you.
Note that comparison is not recursive, if one of the field is an Object, it will be compared to the other
field using its equals method.
If an object has a field and a property with the same name, the property value will be used over the field.
Private fields are used in comparison but this can be disabled using
Assertions.setAllowComparingPrivateFields(boolean), if disabled only accessible fields values are
compared, accessible fields include directly accessible fields (e.g. public) or fields with an accessible getter.
The objects to compare can be of different types but the properties/fields used in comparison must exist in both, for example if actual object has a name String field, it is expected the other object to also have one.
Example:
// equals not overridden in TolkienCharacter
TolkienCharacter frodo = new TolkienCharacter("Frodo", 33, HOBBIT);
TolkienCharacter frodoClone = new TolkienCharacter("Frodo", 33, HOBBIT);
// Fail as equals compares object references
assertThat(frodo).isEqualTo(frodoClone);
// frodo and frodoClone are equals when doing a field by field comparison.
assertThat(frodo).isEqualToComparingFieldByField(frodoClone);other - the object to compare actual to.this assertions objectAssertionError - if the actual object is null.AssertionError - if the actual and the given objects are not equals property/field by property/field.IntrospectionError - if one of actual's property/field to compare can't be found in the other object.protected TypeComparators getComparatorsByType()
public <T> SELF usingComparatorForFields(Comparator<T> comparator, String... propertiesOrFields)
Comparators specified by this method have precedence over comparators added by usingComparatorForType(java.util.Comparator<? super T>, java.lang.Class<T>).
The comparators specified by this method are only used for field by field comparison like isEqualToComparingFieldByField(Object).
When used with isEqualToComparingFieldByFieldRecursively(Object), the fields/properties must be specified from the root object,
for example if Foo class as a Bar field and Bar class has an id, to set a comparator for Bar's id use "bar.id".
Example:
public class TolkienCharacter {
private String name;
private double height;
// constructor omitted
}
TolkienCharacter frodo = new TolkienCharacter("Frodo", 1.2);
TolkienCharacter tallerFrodo = new TolkienCharacter("Frodo", 1.3);
TolkienCharacter reallyTallFrodo = new TolkienCharacter("Frodo", 1.9);
Comparator<Double> closeEnough = new Comparator<Double>() {
double precision = 0.5;
public int compare(Double d1, Double d2) {
return Math.abs(d1 - d2) <= precision ? 0 : 1;
}
};
// assertions will pass
assertThat(frodo).usingComparatorForFields(closeEnough, "height")
.isEqualToComparingFieldByField(tallerFrodo);
assertThat(frodo).usingComparatorForFields(closeEnough, "height")
.isEqualToIgnoringNullFields(tallerFrodo);
assertThat(frodo).usingComparatorForFields(closeEnough, "height")
.isEqualToIgnoringGivenFields(tallerFrodo);
assertThat(frodo).usingComparatorForFields(closeEnough, "height")
.isEqualToComparingOnlyGivenFields(tallerFrodo);
// assertion will fail
assertThat(frodo).usingComparatorForFields(closeEnough, "height")
.isEqualToComparingFieldByField(reallyTallFrodo);T - the type of values to compare.comparator - the Comparator to usepropertiesOrFields - the names of the properties and/or fields the comparator should be used forthis assertions objectpublic <T> SELF usingComparatorForType(Comparator<? super T> comparator, Class<T> type)
Comparators specified by usingComparatorForFields(java.util.Comparator<T>, java.lang.String...) have precedence over comparators specified by this method.
The comparators specified by this method are only used for field by field comparison like isEqualToComparingFieldByField(Object).
Example:
public class TolkienCharacter {
private String name;
private double height;
// constructor omitted
}
TolkienCharacter frodo = new TolkienCharacter("Frodo", 1.2);
TolkienCharacter tallerFrodo = new TolkienCharacter("Frodo", 1.3);
TolkienCharacter reallyTallFrodo = new TolkienCharacter("Frodo", 1.9);
Comparator<Double> closeEnough = new Comparator<Double>() {
double precision = 0.5;
public int compare(Double d1, Double d2) {
return Math.abs(d1 - d2) <= precision ? 0 : 1;
}
};
// assertions will pass
assertThat(frodo).usingComparatorForType(closeEnough, Double.class)
.isEqualToComparingFieldByField(tallerFrodo);
assertThat(frodo).usingComparatorForType(closeEnough, Double.class)
.isEqualToIgnoringNullFields(tallerFrodo);
assertThat(frodo).usingComparatorForType(closeEnough, Double.class)
.isEqualToIgnoringGivenFields(tallerFrodo);
assertThat(frodo).usingComparatorForType(closeEnough, Double.class)
.isEqualToComparingOnlyGivenFields(tallerFrodo);
// assertion will fail
assertThat(frodo).usingComparatorForType(closeEnough, Double.class)
.isEqualToComparingFieldByField(reallyTallFrodo);type, the closest in the inheritance
chain to the given type is chosen in the following order:
typetypetypeT - the type of objects that the comparator should be used forcomparator - the Comparator to usetype - the Class of the type the comparator should be used forthis assertions objectpublic SELF hasFieldOrProperty(String name)
Private fields are matched by default but this can be changed by calling Assertions.setAllowExtractingPrivateFields(false).
Example:
public class TolkienCharacter {
private String name;
private int age;
// constructor omitted
public String getName() {
return this.name;
}
}
TolkienCharacter frodo = new TolkienCharacter("Frodo", 33);
// assertions will pass :
assertThat(frodo).hasFieldOrProperty("name")
.hasFieldOrProperty("age"); // private field are matched by default
// assertions will fail :
assertThat(frodo).hasFieldOrProperty("not_exists");
assertThat(frodo).hasFieldOrProperty(null);
// disable looking for private fields
Assertions.setAllowExtractingPrivateFields(false);
assertThat(frodo).hasFieldOrProperty("age"); name - the field/property name to checkthis assertion object.AssertionError - if the actual object is null.IllegalArgumentException - if name is null.AssertionError - if the actual object does not have the given field/propertypublic SELF hasFieldOrPropertyWithValue(String name, Object value)
Private fields are matched by default but this can be changed by calling Assertions.setAllowExtractingPrivateFields(false).
If you are looking to chain multiple assertions on different properties in a type safe way, consider chaining
returns(Object, Function) and doesNotReturn(Object, Function) calls.
Example:
public class TolkienCharacter {
private String name;
private int age;
// constructor omitted
public String getName() {
return this.name;
}
}
TolkienCharacter frodo = new TolkienCharacter("Frodo", 33);
TolkienCharacter noname = new TolkienCharacter(null, 33);
// assertions will pass :
assertThat(frodo).hasFieldOrPropertyWithValue("name", "Frodo");
assertThat(frodo).hasFieldOrPropertyWithValue("age", 33);
assertThat(noname).hasFieldOrPropertyWithValue("name", null);
// assertions will fail :
assertThat(frodo).hasFieldOrPropertyWithValue("name", "not_equals");
assertThat(frodo).hasFieldOrPropertyWithValue(null, 33);
assertThat(frodo).hasFieldOrPropertyWithValue("age", null);
assertThat(noname).hasFieldOrPropertyWithValue("name", "Frodo");
// disable extracting private fields
Assertions.setAllowExtractingPrivateFields(false);
assertThat(frodo).hasFieldOrPropertyWithValue("age", 33); name - the field/property name to checkvalue - the field/property expected valuethis assertion object.AssertionError - if the actual object is null.IllegalArgumentException - if name is null.AssertionError - if the actual object does not have the given field/propertyAssertionError - if the actual object has the given field/property but not with the expected valuehasFieldOrProperty(java.lang.String)public SELF hasOnlyFields(String... expectedFieldNames)
The assertion only checks declared fields (inherited fields are not checked) that are not static or synthetic.
By default private fields are included in the check, this can be disabled with Assertions.setAllowExtractingPrivateFields(false);
but be mindful this is has a global effect on all field introspection in AssertJ.
Example:
public class TolkienCharacter {
private String name;
public int age;
public String getName() {
return this.name;
}
}
TolkienCharacter frodo = new TolkienCharacter("Frodo", 33);
// assertion succeeds:
assertThat(frodo).hasOnlyFields("name", "age");
// assertions fail:
assertThat(frodo).hasOnlyFields("name");
assertThat(frodo).hasOnlyFields("not_exists");
assertThat(frodo).hasOnlyFields(null);expectedFieldNames - the expected field names actual should havethis assertion object.AssertionError - if the actual object is null.IllegalArgumentException - if expectedFieldNames is null.AssertionError - if the actual object does not have the expected fields (without extra ones)public AbstractListAssert<?,List<?>,Object,ObjectAssert<Object>> extracting(String... propertiesOrFields)
If you extract "id", "name" and "email" fields/properties then the list will contain the id, name and email values of the object under test, you can then perform list assertions on the extracted values.
If the object under test is a Map with String keys, extracting will extract values matching the given fields/properties.
Nested fields/properties are supported, specifying "adress.street.number" is equivalent to:
// "adress.street.number" corresponding to pojo properties
actual.getAdress().getStreet().getNumber();Map:
// "adress" is a Map property (that is getAdress() returns a Map)
actual.getAdress().get("street").getNumber();
Private fields can be extracted unless you call Assertions.setAllowExtractingPrivateFields(false).
Example:
// Create frodo, setting its name, age and Race (Race having a name property)
TolkienCharacter frodo = new TolkienCharacter("Frodo", 33, HOBBIT);
// let's verify Frodo's name, age and race name:
assertThat(frodo).extracting("name", "age", "race.name")
.containsExactly("Frodo", 33, "Hobbit");IntrospectionError is thrown.
Note that the order of extracted values is consistent with the order of the given property/field.
propertiesOrFields - the properties/fields to extract from the initial object under testIntrospectionError - if one of the given name does not match a field or propertypublic AbstractObjectAssert<?,?> extracting(String propertyOrField)
If the object under test is a Map, the propertyOrField parameter is used as a key to the map.
Nested fields/properties are supported, specifying "adress.street.number" is equivalent to:
// "adress.street.number" corresponding to pojo properties
actual.getAdress().getStreet().getNumber();Map:
// "adress" is a Map property (that is getAdress() returns a Map)
actual.getAdress().get("street").getNumber();
Private field can be extracted unless you call Assertions.setAllowExtractingPrivateFields(false).
Note that since the value is extracted as an Object, only Object assertions can be chained after extracting.
Example:
// Create frodo, setting its name, age and Race (Race having a name property)
TolkienCharacter frodo = new TolkienCharacter("Frodo", 33, HOBBIT);
// let's extract and verify Frodo's name:
assertThat(frodo).extracting("name")
.isEqualTo("Frodo");
// or its race name:
assertThat(frodo).extracting("race.name")
.isEqualTo("Hobbit");
// The extracted value being a String, we would like to use String assertions but we can't due to Java generics limitations.
// The following assertion does NOT compile:
assertThat(frodo).extracting("name")
.startsWith("Fro");
// To get String assertions, use extracting(String, InstanceOfAssertFactory):
assertThat(frodo).extracting("name", as(InstanceOfAssertFactories.STRING))
.startsWith("Fro");
A property with the given name is looked for first, if it doesn't exist then a field with the given name is looked
for, if the field is not accessible (i.e. does not exist) an IntrospectionError is thrown.
propertyOrField - the property/field to extract from the initial object under testObjectAssert instance whose object under test is the extracted property/field valueIntrospectionError - if one of the given name does not match a field or propertyextracting(String, InstanceOfAssertFactory)public <ASSERT extends AbstractAssert<?,?>> ASSERT extracting(String propertyOrField, InstanceOfAssertFactory<?,ASSERT> assertFactory)
If the object under test is a Map, the propertyOrField parameter is used as a key to the map.
Nested field/property is supported, specifying "address.street.number" is equivalent to get the value corresponding to actual.getAddress().getStreet().getNumber()
Private field can be extracted unless you call Assertions.setAllowExtractingPrivateFields(false).
The assertFactory parameter allows to specify an InstanceOfAssertFactory, which is used to get the
assertions narrowed to the factory type.
Wrapping the given InstanceOfAssertFactory with Assertions.as(InstanceOfAssertFactory) makes the
assertion more readable.
Example:
// Create frodo, setting its name, age and Race (Race having a name property)
TolkienCharacter frodo = new TolkienCharacter("Frodo", 33, HOBBIT);
// let's extract and verify Frodo's name:
assertThat(frodo).extracting("name", as(InstanceOfAssertFactories.STRING))
.startsWith("Fro");
// The following assertion will fail as Frodo's name is not an Integer:
assertThat(frodo).extracting("name", as(InstanceOfAssertFactories.INTEGER))
.isZero();
A property with the given name is looked for first, if it doesn't exist then a field with the given name is looked
for, if the field is not accessible (i.e. does not exist) an IntrospectionError is thrown.
ASSERT - the type of the resulting AssertpropertyOrField - the property/field to extract from the initial object under testassertFactory - the factory which verifies the type and creates the new AssertAssert instance whose object under test is the extracted property/field valueNullPointerException - if the given factory is nullIntrospectionError - if one of the given name does not match a field or property@SafeVarargs public final AbstractListAssert<?,List<?>,Object,ObjectAssert<Object>> extracting(Function<? super ACTUAL,?>... extractors)
Functions to extract the values from the object under test into a list, this new list becoming
the object under test.
If the given Functions extract the id, name and email values then the list will contain the id, name and email values
of the object under test, you can then perform list assertions on the extracted values.
Example:
// Create frodo, setting its name, age and Race (Race having a name property)
TolkienCharacter frodo = new TolkienCharacter("Frodo", 33, HOBBIT);
// let's verify Frodo's name, age and race name:
assertThat(frodo).extracting(TolkienCharacter::getName,
character -> character.age, // public field
character -> character.getRace().getName())
.containsExactly("Frodo", 33, "Hobbit");Note that the order of extracted values is consistent with the order of given extractor functions.
extractors - the extractor functions to extract values from the Object under test.protected AbstractListAssert<?,List<?>,Object,ObjectAssert<Object>> extractingForProxy(Function<? super ACTUAL,?>[] extractors)
public <T> AbstractObjectAssert<?,T> extracting(Function<? super ACTUAL,T> extractor)
Function to extract a value from the object under test, the extracted value becoming the new object under test.
Note that since the value is extracted as an Object, only Object assertions can be chained after extracting.
Example:
// Create frodo, setting its name, age and Race
TolkienCharacter frodo = new TolkienCharacter("Frodo", 33, HOBBIT);
// let's extract and verify Frodo's name:
assertThat(frodo).extracting(TolkienCharacter::getName)
.isEqualTo("Frodo");
// The extracted value being a String, we would like to use String assertions but we can't due to Java generics limitations.
// The following assertion does NOT compile:
assertThat(frodo).extracting(TolkienCharacter::getName)
.startsWith("Fro");
// To get String assertions, use extracting(Function, InstanceOfAssertFactory):
assertThat(frodo).extracting(TolkienCharacter::getName, as(InstanceOfAssertFactories.STRING))
.startsWith("Fro");T - the expected extracted value type.extractor - the extractor function used to extract the value from the object under test.ObjectAssert instance whose object under test is the extracted valueextracting(Function, InstanceOfAssertFactory)public <T,ASSERT extends AbstractAssert<?,?>> ASSERT extracting(Function<? super ACTUAL,T> extractor, InstanceOfAssertFactory<?,ASSERT> assertFactory)
Function to extract a value from the object under test, the extracted value becoming the new object under test.
Note that since the value is extracted as an Object, only Object assertions can be chained after extracting.
The assertFactory parameter allows to specify an InstanceOfAssertFactory, which is used to get the
assertions narrowed to the factory type.
Wrapping the given InstanceOfAssertFactory with Assertions.as(InstanceOfAssertFactory) makes the
assertion more readable.
Example:
// Create frodo, setting its name, age and Race
TolkienCharacter frodo = new TolkienCharacter("Frodo", 33, HOBBIT);
// let's extract and verify Frodo's name:
assertThat(frodo).extracting(TolkienCharacter::getName, as(InstanceOfAssertFactories.STRING))
.startsWith("Fro");
// The following assertion will fail as Frodo's name is not an Integer:
assertThat(frodo).extracting(TolkienCharacter::getName, as(InstanceOfAssertFactories.INTEGER))
.isZero();T - the expected extracted value typeASSERT - the type of the resulting Assertextractor - the extractor function used to extract the value from the object under testassertFactory - the factory which verifies the type and creates the new AssertAssert instance whose object under test is the extracted valueNullPointerException - if the given factory is null@Deprecated public SELF isEqualToComparingFieldByFieldRecursively(Object other)
usingRecursiveComparison() for comparing objects field by field as it offers more flexibility, better reporting and an easier to use API.
Asserts that the object under test (actual) is equal to the given object based on a recursive property/field by property/field comparison (including
inherited ones). This can be useful if actual's equals implementation does not suit you.
The recursive property/field comparison is not applied on fields having a custom equals implementation, i.e.
the overridden equals method will be used instead of a field by field comparison.
The recursive comparison handles cycles. By default floats are compared with a precision of 1.0E-6 and doubles with 1.0E-15.
You can specify a custom comparator per (nested) fields or type with respectively usingComparatorForFields(Comparator, String...)
and usingComparatorForType(Comparator, Class).
The objects to compare can be of different types but must have the same properties/fields. For example if actual object has a name String field, it is expected the other object to also have one. If an object has a field and a property with the same name, the property value will be used over the field.
Example:
public class Person {
public String name;
public double height;
public Home home = new Home();
public Person bestFriend;
// constructor with name and height omitted for brevity
}
public class Home {
public Address address = new Address();
}
public static class Address {
public int number = 1;
}
Person jack = new Person("Jack", 1.80);
jack.home.address.number = 123;
Person jackClone = new Person("Jack", 1.80);
jackClone.home.address.number = 123;
// cycle are handled in comparison
jack.bestFriend = jackClone;
jackClone.bestFriend = jack;
// will fail as equals compares object references
assertThat(jack).isEqualTo(jackClone);
// jack and jackClone are equals when doing a recursive field by field comparison
assertThat(jack).isEqualToComparingFieldByFieldRecursively(jackClone);
// any type/field can be compared with a a specific comparator.
// let's change jack's height a little bit
jack.height = 1.81;
// assertion fails because of the height difference
// (the default precision comparison for double is 1.0E-15)
assertThat(jack).isEqualToComparingFieldByFieldRecursively(jackClone);
// this succeeds because we allow a 0.5 tolerance on double
assertThat(jack).usingComparatorForType(new DoubleComparator(0.5), Double.class)
.isEqualToComparingFieldByFieldRecursively(jackClone);
// you can set a comparator on specific fields (nested fields are supported)
assertThat(jack).usingComparatorForFields(new DoubleComparator(0.5), "height")
.isEqualToComparingFieldByFieldRecursively(jackClone);other - the object to compare actual to.this assertion object.AssertionError - if the actual object is null.AssertionError - if the actual and the given objects are not deeply equal property/field by property/field.IntrospectionError - if one property/field to compare can not be found.public <T> SELF returns(T expected, Function<ACTUAL,T> from)
Function,
a typical usage is to pass a method reference to assert object's property.
Wrapping the given Function with Assertions.from(Function) makes the assertion more readable.
Example:
// from is not mandatory but it makes the assertions more readable
assertThat(frodo).returns("Frodo", from(TolkienCharacter::getName))
.returns("Frodo", TolkienCharacter::getName) // no from :(
.returns(HOBBIT, from(TolkienCharacter::getRace));T - the expected value type the given method returns.expected - the value the object under test method's call should return.from - Function used to acquire the value to test from the object under test. Must not be nullthis assertion object.NullPointerException - if given from function is nullpublic <T> SELF doesNotReturn(T expected, Function<ACTUAL,T> from)
Function,
a typical usage is to pass a method reference to assert object's property.
Wrapping the given Function with Assertions.from(Function) makes the assertion more readable.
Example:
// from is not mandatory but it makes the assertions more readable
assertThat(frodo).doesNotReturn("Bilbo", from(TolkienCharacter::getName))
.doesNotReturn("Bilbo", TolkienCharacter::getName) // no from :(
.doesNotReturn(null, from(TolkienCharacter::getRace));T - the expected value type the given method returns.expected - the value the object under test method's call should not return.from - Function used to acquire the value to test from the object under test. Must not be nullthis assertion object.NullPointerException - if given from function is nullpublic RecursiveComparisonAssert<?> usingRecursiveComparison()
isEqualTo assertion.
The detailed documentation is available here: https://assertj.github.io/doc/#assertj-core-recursive-comparison.
Example:
public class Person {
String name;
double height;
Home home = new Home();
}
public class Home {
Address address = new Address();
Date ownedSince;
}
public static class Address {
int number;
String street;
}
Person sherlock = new Person("Sherlock", 1.80);
sherlock.home.ownedSince = new Date(123);
sherlock.home.address.street = "Baker Street";
sherlock.home.address.number = 221;
Person sherlock2 = new Person("Sherlock", 1.80);
sherlock2.home.ownedSince = new Date(123);
sherlock2.home.address.street = "Baker Street";
sherlock2.home.address.number = 221;
// assertion succeeds as the data of both objects are the same.
assertThat(sherlock).usingRecursiveComparison()
.isEqualTo(sherlock2);
// assertion fails because sherlock.equals(sherlock2) is false.
assertThat(sherlock).isEqualTo(sherlock2);
The recursive comparison is performed according to the default RecursiveComparisonConfiguration that is:
withStrictTypeChecking() to change that behavior). usingComparatorForType(Comparator, Class) It is possible to change the comparison behavior, among things what you can is:
Book and BookDto Please consult the detailed documentation available here: https://assertj.github.io/doc/#assertj-core-recursive-comparison
usingRecursiveComparison in class AbstractAssert<SELF extends AbstractObjectAssert<SELF,ACTUAL>,ACTUAL>RecursiveComparisonAssert instancepublic RecursiveComparisonAssert<?> usingRecursiveComparison(RecursiveComparisonConfiguration recursiveComparisonConfiguration)
usingRecursiveComparison() but allows to specify your own RecursiveComparisonConfiguration.usingRecursiveComparison in class AbstractAssert<SELF extends AbstractObjectAssert<SELF,ACTUAL>,ACTUAL>recursiveComparisonConfiguration - the RecursiveComparisonConfiguration used in the chained isEqualTo assertion.RecursiveComparisonAssert instance built with the given RecursiveComparisonConfiguration.protected <T> AbstractObjectAssert<?,T> newObjectAssert(T objectUnderTest)
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