Package org.hamcrest.core
Class IsNull<T>
- java.lang.Object
- org.hamcrest.BaseMatcher<T>
- org.hamcrest.core.IsNull<T>
- All Implemented Interfaces:
Matcher<T>
,SelfDescribing
public class IsNull<T> extends BaseMatcher<T>
Is the value null?
Constructor Summary
Constructors Constructor Description IsNull()
Method Summary
All Methods Static Methods Instance Methods Concrete Methods Modifier and Type Method Description void
describeTo(Description description)
Generates a description of the object.boolean
matches(Object o)
Evaluates the matcher for argument item.static Matcher<Object>
notNullValue()
A shortcut to the frequently usednot(nullValue())
.static <T> Matcher<T>
notNullValue(Class<T> type)
A shortcut to the frequently usednot(nullValue(X.class)).
static Matcher<Object>
nullValue()
Creates a matcher that matches if examined object isnull
.static <T> Matcher<T>
nullValue(Class<T> type)
Creates a matcher that matches if examined object isnull
.Methods inherited from class org.hamcrest.BaseMatcher
_dont_implement_Matcher___instead_extend_BaseMatcher_, describeMismatch, toString
Constructor Detail
IsNull
public IsNull()
Method Detail
matches
public boolean matches(Object o)
Description copied from interface:Matcher
Evaluates the matcher for argument item. This method matches against Object, instead of the generic type T. This is because the caller of the Matcher does not know at runtime what the type is (because of type erasure with Java generics). It is down to the implementations to check the correct type.- Parameters:
o
- the object against which the matcher is evaluated.- Returns:
true
if item matches, otherwisefalse
.- See Also:
BaseMatcher
describeTo
public void describeTo(Description description)
Description copied from interface:SelfDescribing
Generates a description of the object. The description may be part of a a description of a larger object of which this is just a component, so it should be worded appropriately.- Parameters:
description
- The description to be built or appended to.
nullValue
public static Matcher<Object> nullValue()
Creates a matcher that matches if examined object isnull
. For example:assertThat(cheese, is(nullValue())
notNullValue
public static Matcher<Object> notNullValue()
A shortcut to the frequently usednot(nullValue())
. For example:assertThat(cheese, is(notNullValue()))
instead of:assertThat(cheese, is(not(nullValue())))
nullValue
public static <T> Matcher<T> nullValue(Class<T> type)
Creates a matcher that matches if examined object isnull
. Accepts a single dummy argument to facilitate type inference. For example:assertThat(cheese, is(nullValue(Cheese.class))
- Parameters:
type
- dummy parameter used to infer the generic type of the returned matcher
notNullValue
public static <T> Matcher<T> notNullValue(Class<T> type)
A shortcut to the frequently usednot(nullValue(X.class)). Accepts a single dummy argument to facilitate type inference.
. For example:assertThat(cheese, is(notNullValue(X.class)))
instead of:assertThat(cheese, is(not(nullValue(X.class))))
- Parameters:
type
- dummy parameter used to infer the generic type of the returned matcher