Subject (Truth 0.45)

java.lang.Object
- com.google.common.truth.Subject<S,T>

Type Parameters:

S - deprecated - the self-type, allowing this-returning methods to avoid needing subclassing. Both type parameters will be removed, as the methods that need them are being removed. You can prepare for this change by editing your class to refer to raw Subject today.

T - deprecated - the type of the object being tested by this Subject. Both type parameters will be removed, as the methods that need them are being removed. You can prepare for this change by editing your class to refer to raw Subject today.

Direct Known Subclasses:

AtomicLongMapSubject, BooleanSubject, ClassSubject, ComparableSubject, DefaultSubject, GuavaOptionalSubject, IntStreamSubject, IterableSubject, LiteProtoSubject, LongStreamSubject, MapSubject, MultimapSubject, ObjectArraySubject, OptionalDoubleSubject, OptionalIntSubject, OptionalLongSubject, OptionalSubject, PathSubject, PrimitiveBooleanArraySubject, PrimitiveByteArraySubject, PrimitiveCharArraySubject, PrimitiveDoubleArraySubject, PrimitiveFloatArraySubject, PrimitiveIntArraySubject, PrimitiveLongArraySubject, PrimitiveShortArraySubject, Re2jSubjects.Re2jStringSubject, StreamSubject, TableSubject, ThrowableSubject
```
public class Subject<S extends Subject<S,T>,T>
extends Object
```
An object that lets you perform checks on the value under test. For example, Subject contains isEqualTo(Object) and isInstanceOf(Class), and StringSubject contains startsWith(String).
To create a Subject instance, most users will call an assertThat method. For information about other ways to create an instance, see this FAQ entry.
For people extending Truth

For information about writing a custom Subject, see our doc on extensions.

Author:

David Saff, Christian Gruber

Nested Class Summary

Nested Classes
Modifier and Type	Class and Description
`static interface`	`Subject.Factory<SubjectT extends Subject,ActualT>` In a fluent assertion chain, the argument to the common overload of `about`, the method that specifies what kind of `Subject` to create.

Constructor Summary

Constructors
Modifier Constructor and Description

protected Subject(FailureMetadata metadata, T actual)
Constructor for use by subclasses.

Constructors
Modifier	Constructor and Description
`protected`	`Subject(FailureMetadata metadata, T actual)` Constructor for use by subclasses.

Method Summary

All Methods Instance Methods Concrete Methods Deprecated Methods
Modifier and Type	Method and Description
`protected T`	`actual()` Deprecated. Instead, declare a private field to store the actual value inside your `Subject` subclass. We will be releasing a tool to automate most migrations.
`protected String`	`actualAsString()` Deprecated. Now that `named(java.lang.String, java.lang.Object...)` is being removed, this method simply returns `actualCustomStringRepresentation()`, surrounded by angle brackets (and we discourage angle brackets in the new key-value style of failure messages). Most callers can use the actual value directly instead. If they format it in `actualCustomStringRepresentation()`, they may wish to apply similar formatting here.
`protected String`	`actualCustomStringRepresentation()` Supplies the direct string representation of the actual value to other methods which may prefix or otherwise position it in an error message.
`protected StandardSubjectBuilder`	`check(String format, Object... args)` Returns a builder for creating a derived subject.
`boolean`	`equals(Object o)` Deprecated. `Object.equals(Object)` is not supported on Truth subjects. If you meant to test object equality between an expected and the actual value, use `isEqualTo(Object)` instead.
`protected void`	`failWithActual(Fact first, Fact... rest)` Fails, reporting a message with the given facts, followed by an automatically added fact of the form: but was: actual value.
`protected void`	`failWithActual(String key, Object value)` Fails, reporting a message with two "facts": key: value but was: actual value.
`protected void`	`failWithoutActual(Fact first, Fact... rest)` Fails, reporting a message with the given facts, without automatically adding the actual value.
`protected T`	`getSubject()` Deprecated. Instead, declare a private field to store the actual value inside your `Subject` subclass. We will be releasing a tool to automate most migrations.
`int`	`hashCode()` Deprecated. `Object.hashCode()` is not supported on Truth subjects.
`protected StandardSubjectBuilder`	`ignoreCheck()` Begins a new call chain that ignores any failures.
`protected String`	`internalCustomName()` Deprecated. This method will be removed when `named(java.lang.String, java.lang.Object...)` is.
`void`	`isAnyOf(Object first, Object second, Object... rest)` Fails unless the subject is equal to any of the given elements.
`void`	`isEqualTo(Object expected)` Fails if the subject is not equal to the given object.
`void`	`isIn(Iterable<?> iterable)` Fails unless the subject is equal to any element in the given iterable.
`void`	`isInstanceOf(Class<?> clazz)` Fails if the subject is not an instance of the given class.
`void`	`isNoneOf(Object first, Object second, Object... rest)` Fails if the subject is equal to any of the given elements.
`void`	`isNotEqualTo(Object unexpected)` Fails if the subject is equal to the given object.
`void`	`isNotIn(Iterable<?> iterable)` Fails if the subject is equal to any element in the given iterable.
`void`	`isNotInstanceOf(Class<?> clazz)` Fails if the subject is an instance of the given class.
`void`	`isNotNull()` Fails if the subject is null.
`void`	`isNotSameInstanceAs(Object unexpected)` Fails if the subject is the same instance as the given object.
`void`	`isNull()` Fails if the subject is not null.
`void`	`isSameInstanceAs(Object expected)` Fails if the subject is not the same instance as the given object.
`S`	`named(String format, Object... args)` Deprecated. Instead of `assertThat(foo).named("foo")`, use `assertWithMessage("foo").that(foo)`. For custom subjects, use `assertWithMessage("foo").about(foos()).that(foo)`. For other scenarios, see this FAQ entry about adding messages. We will be releasing a tool to automate most migrations.
`String`	`toString()`

Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, wait, wait, wait

- Constructor Detail
  - Subject
```
protected Subject(FailureMetadata metadata,
                  @NullableDecl
                  T actual)
```
    Constructor for use by subclasses. If you want to create an instance of this class itself, call check().that(actual).
- Method Detail
  - internalCustomName
```
@Deprecated
protected String internalCustomName()
```
    Deprecated. This method will be removed when named(java.lang.String, java.lang.Object...) is.
    
    An internal method used to obtain the value set by named(String, Object...).
  - named
```
@CanIgnoreReturnValue
 @Deprecated
public S named(String format,
                                                  Object... args)
```
    Deprecated. Instead of assertThat(foo).named("foo"), use assertWithMessage("foo").that(foo). For custom subjects, use assertWithMessage("foo").about(foos()).that(foo). For other scenarios, see this FAQ entry about adding messages. We will be releasing a tool to automate most migrations.
    
    Adds a prefix to the subject, when it is displayed in error messages. This is especially useful in the context of types that have no helpful toString() representation, e.g. boolean. Writing assertThat(foo).named("foo").isTrue(); then results in a more reasonable error message.
    named() takes a format template and argument objects which will be substituted into the template using Strings.lenientFormat. Note this only supports the %s specifier.
    
    Parameters:
    
    format - a template with %s placeholders
    
    args - the object parameters which will be applied to the message template.
  - isNull
```
public void isNull()
```
    Fails if the subject is not null.
  - isNotNull
```
public void isNotNull()
```
    Fails if the subject is null.
  - isEqualTo
```
public void isEqualTo(@NullableDecl
                      Object expected)
```
    Fails if the subject is not equal to the given object. For the purposes of this comparison, two objects are equal if any of the following is true:
    - they are equal according to Objects.equal(java.lang.Object, java.lang.Object)
    - they are arrays and are considered equal by the appropriate Arrays.equals(long[], long[]) overload
    - they are boxed integer types (Byte, Short, Character, Integer, or Long) and they are numerically equal when converted to Long.
    Note: This method does not test the Object.equals(java.lang.Object) implementation itself; it assumes that method is functioning correctly according to its contract. Testing an equals implementation requires a utility such as guava-testlib's EqualsTester.
  - isNotEqualTo
```
public void isNotEqualTo(@NullableDecl
                         Object unexpected)
```
    Fails if the subject is equal to the given object. The meaning of equality is the same as for the isEqualTo(java.lang.Object) method.
  - isSameInstanceAs
```
public final void isSameInstanceAs(@NullableDecl @CompatibleWith(value="T")
                                   Object expected)
```
    Fails if the subject is not the same instance as the given object.
  - isNotSameInstanceAs
```
public final void isNotSameInstanceAs(@NullableDecl @CompatibleWith(value="T")
                                      Object unexpected)
```
    Fails if the subject is the same instance as the given object.
  - isInstanceOf
```
public void isInstanceOf(Class<?> clazz)
```
    Fails if the subject is not an instance of the given class.
  - isNotInstanceOf
```
public void isNotInstanceOf(Class<?> clazz)
```
    Fails if the subject is an instance of the given class.
  - isIn
```
public void isIn(Iterable<?> iterable)
```
    Fails unless the subject is equal to any element in the given iterable.
  - isAnyOf
```
public void isAnyOf(@NullableDecl @CompatibleWith(value="T")
                    Object first,
                    @NullableDecl @CompatibleWith(value="T")
                    Object second,
                    @NullableDecl
                    Object... rest)
```
    Fails unless the subject is equal to any of the given elements.
  - isNotIn
```
public void isNotIn(Iterable<?> iterable)
```
    Fails if the subject is equal to any element in the given iterable.
  - isNoneOf
```
public void isNoneOf(@NullableDecl @CompatibleWith(value="T")
                     Object first,
                     @NullableDecl @CompatibleWith(value="T")
                     Object second,
                     @NullableDecl
                     Object... rest)
```
    Fails if the subject is equal to any of the given elements.
  - getSubject
```
@Deprecated
protected T getSubject()
```
    Deprecated. Instead, declare a private field to store the actual value inside your Subject subclass. We will be releasing a tool to automate most migrations.
    
    Returns the unedited, unformatted raw actual value.
  - actual
```
@Deprecated
protected final T actual()
```
    Deprecated. Instead, declare a private field to store the actual value inside your Subject subclass. We will be releasing a tool to automate most migrations.
    
    Returns the unedited, unformatted raw actual value.
  - actualAsString
```
@Deprecated
protected final String actualAsString()
```
    Deprecated. Now that named(java.lang.String, java.lang.Object...) is being removed, this method simply returns actualCustomStringRepresentation(), surrounded by angle brackets (and we discourage angle brackets in the new key-value style of failure messages). Most callers can use the actual value directly instead. If they format it in actualCustomStringRepresentation(), they may wish to apply similar formatting here.
    
    Returns a string representation of the actual value. This will either be the toString() of the value or a prefixed "name" along with the string representation.
  - actualCustomStringRepresentation
```
@ForOverride
protected String actualCustomStringRepresentation()
```
    Supplies the direct string representation of the actual value to other methods which may prefix or otherwise position it in an error message. This should only be overridden to provide an improved string representation of the value under test, as it would appear in any given error message, and should not be used for additional prefixing.
    Subjects should override this with care.
    By default, this returns String.ValueOf(getActualValue()).
  - check
```
protected final StandardSubjectBuilder check(String format,
                                             Object... args)
```
    Returns a builder for creating a derived subject.
    Derived subjects retain the FailureStrategy and messages of the current subject, and in some cases, they automatically supplement their failure message with information about the original subject.
    For example, ThrowableSubject.hasMessageThat(), which returns a StringSubject, is implemented with check("getMessage()").that(actual().getMessage()).
    The arguments to check describe how the new subject was derived from the old, formatted like a chained method call. This allows Truth to include that information in its failure messages. For example, assertThat(caught).hasCauseThat().hasMessageThat() will produce a failure message that includes the string "throwable.getCause().getMessage()," thanks to internal check calls that supplied "getCause()" and "getMessage()" as arguments.
    If the method you're delegating to accepts parameters, you can pass check a format string. For example, MultimapSubject.valuesForKey(java.lang.Object) calls check("valuesForKey(%s)", key).
    If you aren't really delegating to an instance method on the actual value -- maybe you're calling a static method, or you're calling a chain of several methods -- you can supply whatever string will be most useful to users. For example, if you're delegating to getOnlyElement(actual().colors()), you might call check("onlyColor()").
    
    Parameters:
    
    format - a template with %s placeholders
    
    args - the arguments to be inserted into those placeholders
  - ignoreCheck
```
protected final StandardSubjectBuilder ignoreCheck()
```
    Begins a new call chain that ignores any failures. This is useful for subjects that normally delegate with to other subjects by using check() but have already reported a failure. In such cases it may still be necessary to return a Subject instance even though any subsequent assertions are meaningless. For example, if a user chains together more ThrowableSubject.hasCauseThat() calls than the actual exception has causes, hasCauseThat returns ignoreCheck().that(... a dummy exception ...).
  - failWithActual
```
protected final void failWithActual(String key,
                                    @NullableDecl
                                    Object value)
```
    Fails, reporting a message with two "facts":
    - key: value
    - but was: actual value.
    This is the simplest failure API. For more advanced needs, see the other overload and failWithoutActual.
    Example usage: The check contains(String) calls failWithActual("expected to contain", string).
  - failWithActual
```
protected final void failWithActual(Fact first,
                                    Fact... rest)
```
    Fails, reporting a message with the given facts, followed by an automatically added fact of the form:
    - but was: actual value.
    If you have only one fact to report (and it's a key-value fact), prefer the simpler overload.
    Example usage: The check isEmpty() calls failWithActual(simpleFact("expected to be empty")).
  - failWithoutActual
```
protected final void failWithoutActual(Fact first,
                                       Fact... rest)
```
    Fails, reporting a message with the given facts, without automatically adding the actual value.
    Most failure messages should report the actual value, so most checks should call failWithActual instead. However, failWithoutActual is useful in some cases:
    - when the actual value is obvious from the rest of the message. For example, isNotEmpty() calls failWithoutActual(simpleFact("expected not to be empty").
    - when the actual value shouldn't come last or should have a different key than the default of "but was." For example, isNotWithin(...).of(...) calls failWithoutActual so that it can put the expected and actual values together, followed by the tolerance.
    Example usage: The check isEmpty() calls failWithActual(simpleFact("expected to be empty")).
  - equals
```
@Deprecated
public final boolean equals(@NullableDecl
                                        Object o)
```
    Deprecated. Object.equals(Object) is not supported on Truth subjects. If you meant to test object equality between an expected and the actual value, use isEqualTo(Object) instead.
    
    Overrides:
    
    equals in class Object
    
    Throws:
    
    UnsupportedOperationException - always
  - hashCode
```
@Deprecated
public final int hashCode()
```
    Deprecated. Object.hashCode() is not supported on Truth subjects.
    
    Overrides:
    
    hashCode in class Object
    
    Throws:
    
    UnsupportedOperationException - always
  - toString
```
public String toString()
```
    Overrides:
    
    toString in class Object

Class Subject<S extends Subject<S,T>,T>

For people extending Truth

Nested Class Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

Subject

Method Detail

internalCustomName

named

isNull

isNotNull

isEqualTo

isNotEqualTo

isSameInstanceAs

isNotSameInstanceAs

isInstanceOf

isNotInstanceOf

isIn

isAnyOf

isNotIn

isNoneOf

getSubject

actual

actualAsString

actualCustomStringRepresentation

check

ignoreCheck

failWithActual

failWithActual

failWithoutActual

equals

hashCode

toString