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How to use IsNull class of org.hamcrest.core package

Best junit code snippet using org.hamcrest.core.IsNull

Source:CoreMatchers.java

...11import org.hamcrest.core.IsCollectionContaining;12import org.hamcrest.core.IsEqual;13import org.hamcrest.core.IsInstanceOf;14import org.hamcrest.core.IsNot;15import org.hamcrest.core.IsNull;16import org.hamcrest.core.IsSame;17import org.hamcrest.core.StringContains;18import org.hamcrest.core.StringEndsWith;19import org.hamcrest.core.StringStartsWith;20public class CoreMatchers {21    public static <T> Matcher<T> allOf(Iterable<Matcher<? super T>> matchers) {22        return AllOf.allOf((Iterable) matchers);23    }24    @SafeVarargs25    public static <T> Matcher<T> allOf(Matcher<? super T>... matchers) {26        return AllOf.allOf((Matcher[]) matchers);27    }28    public static <T> AnyOf<T> anyOf(Iterable<Matcher<? super T>> matchers) {29        return AnyOf.anyOf((Iterable) matchers);30    }31    @SafeVarargs32    public static <T> AnyOf<T> anyOf(Matcher<? super T>... matchers) {33        return AnyOf.anyOf((Matcher[]) matchers);34    }35    public static <LHS> CombinableBothMatcher<LHS> both(Matcher<? super LHS> matcher) {36        return CombinableMatcher.both(matcher);37    }38    public static <LHS> CombinableEitherMatcher<LHS> either(Matcher<? super LHS> matcher) {39        return CombinableMatcher.either(matcher);40    }41    public static <T> Matcher<T> describedAs(String description, Matcher<T> matcher, Object... values) {42        return DescribedAs.describedAs(description, matcher, values);43    }44    public static <U> Matcher<Iterable<? extends U>> everyItem(Matcher<U> itemMatcher) {45        return Every.everyItem(itemMatcher);46    }47    public static <T> Matcher<T> is(Matcher<T> matcher) {48        return Is.is((Matcher) matcher);49    }50    public static <T> Matcher<T> is(T value) {51        return Is.is((Object) value);52    }53    public static void is(Class<?> cls) {54    }55    public static <T> Matcher<T> isA(Class<T> type) {56        return Is.isA(type);57    }58    public static Matcher<Object> anything() {59        return IsAnything.anything();60    }61    public static Matcher<Object> anything(String description) {62        return IsAnything.anything(description);63    }64    public static <T> Matcher<Iterable<? super T>> hasItem(Matcher<? super T> itemMatcher) {65        return IsCollectionContaining.hasItem((Matcher) itemMatcher);66    }67    public static <T> Matcher<Iterable<? super T>> hasItem(T item) {68        return IsCollectionContaining.hasItem((Object) item);69    }70    @SafeVarargs71    public static <T> Matcher<Iterable<T>> hasItems(Matcher<? super T>... itemMatchers) {72        return IsCollectionContaining.hasItems((Matcher[]) itemMatchers);73    }74    @SafeVarargs75    public static <T> Matcher<Iterable<T>> hasItems(T... items) {76        return IsCollectionContaining.hasItems((Object[]) items);77    }78    public static <T> Matcher<T> equalTo(T operand) {79        return IsEqual.equalTo(operand);80    }81    public static Matcher<Object> equalToObject(Object operand) {82        return IsEqual.equalToObject(operand);83    }84    public static <T> Matcher<T> any(Class<T> type) {85        return IsInstanceOf.any(type);86    }87    public static <T> Matcher<T> instanceOf(Class<?> type) {88        return IsInstanceOf.instanceOf(type);89    }90    public static <T> Matcher<T> not(Matcher<T> matcher) {91        return IsNot.not((Matcher) matcher);92    }93    public static <T> Matcher<T> not(T value) {94        return IsNot.not((Object) value);95    }96    public static Matcher<Object> notNullValue() {97        return IsNull.notNullValue();98    }99    public static <T> Matcher<T> notNullValue(Class<T> type) {100        return IsNull.notNullValue(type);101    }102    public static Matcher<Object> nullValue() {103        return IsNull.nullValue();104    }105    public static <T> Matcher<T> nullValue(Class<T> type) {106        return IsNull.nullValue(type);107    }108    public static <T> Matcher<T> sameInstance(T target) {109        return IsSame.sameInstance(target);110    }111    public static <T> Matcher<T> theInstance(T target) {112        return IsSame.theInstance(target);113    }114    public static Matcher<String> containsString(String substring) {115        return StringContains.containsString(substring);116    }117    public static Matcher<String> containsStringIgnoringCase(String substring) {118        return StringContains.containsStringIgnoringCase(substring);119    }120    public static Matcher<String> startsWith(String prefix) {...

IsNull

Using AI Code Generation

1import static org.hamcrest.core.IsNull.nullValue;2import static org.hamcrest.core.IsNull.notNullValue;3import static org.hamcrest.MatcherAssert.assertThat;4import static org.hamcrest.Matchers.is;5import org.junit.Test;6public class IsNullTest {7    public void testNullValue() {8        String str = null;9        assertThat(str, nullValue());10    }11    public void testNotNullValue() {12        String str = "foo";13        assertThat(str, notNullValue());14    }15    public void testIs() {16        String str = "foo";17        assertThat(str, is("foo"));18    }19}20    at org.junit.Assert.assertEquals(Assert.java:115)21    at org.junit.Assert.assertEquals(Assert.java:144)22    at com.baeldung.hamcrest.IsNullTest.testNullValue(IsNullTest.java:19)23    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)24    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)25    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)26    at java.lang.reflect.Method.invoke(Method.java:498)27    at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50)28    at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)29    at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47)30    at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)31    at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:26)32    at org.junit.internal.runners.statements.RunAfters.evaluate(RunAfters.java:27)33    at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325)34    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:78)35    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:57)36    at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)37    at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)38    at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)

Source: How to check a string against null in java?

1public interface ConnectRetryPolicy {2 void doRetryDelay();3}4

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