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How to use theInstance method of org.hamcrest.CoreMatchers class

Best junit code snippet using org.hamcrest.CoreMatchers.theInstance

Source:HamcrestCoreMatchersTest.java

...22import static org.hamcrest.CoreMatchers.nullValue;23import static org.hamcrest.CoreMatchers.sameInstance;24import static org.hamcrest.CoreMatchers.startsWith;25import static org.hamcrest.CoreMatchers.startsWithIgnoringCase;26import static org.hamcrest.CoreMatchers.theInstance;27import static org.hamcrest.MatcherAssert.assertThat;28import java.util.List;29import org.junit.jupiter.api.Test;30import com.google.common.collect.Lists;3132public class HamcrestCoreMatchersTest {3334  @Test35  public void givenTestInput_WhenUsingIsForMatch() {3637    // GIVEN38    String testString = "hamcrest core";3940    // ASSERT41    assertThat(testString, is("hamcrest core"));42    assertThat(testString, is(equalTo("hamcrest core")));43  }4445  @Test46  public void givenDifferentStaticTypeTestInput_WhenUsingEqualToObject_ThenCorrect() {4748    // GIVEN49    Object original = 100;5051    // ASSERT52    assertThat(original, equalToObject(100));53  }5455  @Test56  public void givenTestInput_WhenUsingInstanceOfForClassTypeCheck() {5758    assertThat("hamcrest", is(instanceOf(String.class)));59  }6061  @Test62  public void givenTestInput_WhenUsingIsA_ThenAssertType() {6364    assertThat("hamcrest core", isA(String.class));65  }6667  @Test68  public void givenTestInput_WhenUsingEqualToMatcherForEquality() {6970    // GIVEN71    String actualString = "Hamcrest Core";72    List<String> actualList = Lists.newArrayList("hamcrest", "core");7374    // ASSERT75    assertThat(actualString, is(equalTo("Hamcrest Core")));76    assertThat(actualList, is(equalTo(Lists.newArrayList("hamcrest", "core"))));77  }7879  @Test80  public void givenTestInput_WhenUsingNotForMatch() {8182    // GIVEN83    String testString = "hamcrest";8485    // ASSERT86    assertThat(testString, not("hamcrest core"));87    assertThat(testString, is(not(equalTo("hamcrest core"))));88    assertThat(testString, is(not(instanceOf(Integer.class))));89  }9091  @Test92  public void givenTestInput_WhenUsingNullValueForNullCheck() {9394    // GIVEN95    Integer nullObject = null;9697    // ASSERT98    assertThat(nullObject, is(nullValue()));99    assertThat(nullObject, is(nullValue(Integer.class)));100  }101102  @Test103  public void givenTestInput_WhenUsingNotNullValueForNotNullCheck() {104105    // GIVEN106    Integer testNumber = 123;107108    // ASSERT109    assertThat(testNumber, is(notNullValue()));110    assertThat(testNumber, is(notNullValue(Integer.class)));111  }112113  @Test114  public void givenString_WhenStartsWith_ThenCorrect() {115116    // GIVEN117    String testString = "hamcrest core";118119    // ASSERT120    assertThat(testString, startsWith("hamcrest"));121  }122123  @Test124  public void giveString_WhenStartsWithIgnoringCase_ThenCorrect() {125126    // GIVEN127    String testString = "hamcrest core";128129    // ASSERT130    assertThat(testString, startsWithIgnoringCase("HAMCREST"));131  }132133  @Test134  public void givenString_WhenEndsWith_ThenCorrect() {135136    // GIVEN137    String testString = "hamcrest core";138139    // ASSERT140    assertThat(testString, endsWith("core"));141  }142143  @Test144  public void givenString_WhenEndsWithIgnoringCase_ThenCorrect() {145146    // GIVEN147    String testString = "hamcrest core";148149    // ASSERT150    assertThat(testString, endsWithIgnoringCase("CORE"));151  }152153  @Test154  public void givenString_WhenContainsString_ThenCorrect() {155156    // GIVEN157    String testString = "hamcrest core";158159    // ASSERT160    assertThat(testString, containsString("co"));161  }162163  @Test164  public void givenString_WhenContainsStringIgnoringCase_ThenCorrect() {165166167    // GIVEN168    String testString = "hamcrest core";169170    // ASSERT171    assertThat(testString, containsStringIgnoringCase("CO"));172  }173174  @Test175  public void givenTestInput_WhenUsingHasItemInCollection() {176177    // GIVEN178    List<String> list = Lists.newArrayList("java", "spring", "baeldung");179180    // ASSERT181    assertThat(list, hasItem("java"));182    assertThat(list, hasItem(isA(String.class)));183  }184185186  @Test187  public void givenTestInput_WhenUsingHasItemsInCollection() {188189    // GIVEN190    List<String> list = Lists.newArrayList("java", "spring", "baeldung");191192    // ASSERT193    assertThat(list, hasItems("java", "baeldung"));194    assertThat(list, hasItems(isA(String.class), endsWith("ing")));195  }196197  @Test198  public void givenTestInput_WhenUsingAnyForClassType() {199200    assertThat("hamcrest", is(any(String.class)));201    assertThat("hamcrest", is(any(Object.class)));202  }203204  @Test205  public void givenTestInput_WhenUsingAllOfForAllMatchers() {206207    // GIVEN208    String testString = "Hamcrest Core";209210    // ASSERT211    assertThat(testString, allOf(startsWith("Ham"), endsWith("ore"), containsString("Core")));212  }213214  @Test215  public void givenTestInput_WhenUsingAnyOfForAnyMatcher() {216217    // GIVEN218    String testString = "Hamcrest Core";219220    // ASSERT221    assertThat(testString, anyOf(startsWith("Ham"), containsString("baeldung")));222  }223224  @Test225  public void givenTestInput_WhenUsingBothForMatcher() {226227    // GIVEN228    String testString = "Hamcrest Core Matchers";229230    // ASSERT231    assertThat(testString, both(startsWith("Ham")).and(containsString("Core")));232  }233234  @Test235  public void givenTestInput_WhenUsingEitherForMatcher() {236237    // GIVEN238    String testString = "Hamcrest Core Matchers";239240    // ASSERT241    assertThat(testString, either(startsWith("Bael")).or(containsString("Core")));242  }243244245  @Test246  public void givenTestInput_WhenUsingEveryItemForMatchInCollection() {247248    // GIVEN249    List<String> testItems = Lists.newArrayList("Common", "Core", "Combinable");250251    // ASSERT252    assertThat(testItems, everyItem(startsWith("Co")));253  }254255  @Test256  public void givenTwoTestInputs_WhenUsingSameInstanceForMatch() {257258    // GIVEN259    String string1 = "hamcrest";260    String string2 = string1;261262    // ASSERT263    assertThat(string1, is(sameInstance(string2)));264  }265266  @Test267  public void givenTwoTestInputs_WhenUsingTheInstanceForMatch() {268    // GIVEN269    String string1 = "hamcrest";270    String string2 = string1;271272    // ASSERT273    assertThat(string1, is(theInstance(string2)));274  }275276}277
...

Source:ThreadPoolSupplierTest.java

...122        } finally {123            log.removeHandler(handler);124        }125    }126    private void testInstance(ThreadPoolExecutor theInstance,127                              String namePrefix,128                              int corePoolSize,129                              int queueCapacity,130                              int poolSize,131                              boolean shouldBeDaemon) throws ExecutionException, InterruptedException {132        // test that we did indeed create an executor service133        assertThat(theInstance, notNullValue());134        // test that pool size is configured correctly135        assertThat(theInstance.getCorePoolSize(), is(corePoolSize));136        // test that queue-capacity is configured correctly137        assertThat(theInstance.getQueue().remainingCapacity(), is(queueCapacity));138        // test that prestart is configured correctly139        assertThat(theInstance.getPoolSize(), is(poolSize));140        AtomicReference<String> threadName = new AtomicReference<>();141        theInstance142            .submit(() -> threadName.set(Thread.currentThread().getName()))143            .get();144        assertThat(threadName.get(), startsWith(namePrefix));145        AtomicReference<Boolean> isDaemon = new AtomicReference<>();146        theInstance147            .submit(() -> isDaemon.set(Thread.currentThread().isDaemon()))148            .get();149        assertThat(isDaemon.get(), is(shouldBeDaemon));150    }151}...

Source:ScheduledThreadPoolSupplierTest.java

...64                "scheduled-thread-pool-unit-test-",65                2,66                true);67    }68    private void testInstance(ScheduledThreadPoolExecutor theInstance,69                              String namePrefix,70                              int corePoolSize,71                              boolean shouldBeDaemon) throws ExecutionException, InterruptedException {72        // test that we did indeed create an executor service73        assertThat(theInstance, notNullValue());74        // test that pool size is configured correctly75        assertThat(theInstance.getCorePoolSize(), is(corePoolSize));76        AtomicReference<String> threadName = new AtomicReference<>();77        theInstance.submit(() -> threadName.set(Thread.currentThread().getName())).get();78        assertThat(threadName.get(), startsWith(namePrefix));79        AtomicReference<Boolean> isDaemon = new AtomicReference<>();80        theInstance.submit(() -> isDaemon.set(Thread.currentThread().isDaemon())) .get();81        assertThat(isDaemon.get(), is(shouldBeDaemon));82    }83}...

Source:AssertThatTest.java

...19import static org.hamcrest.CoreMatchers.not;20import static org.hamcrest.CoreMatchers.nullValue;21import static org.hamcrest.CoreMatchers.sameInstance;22import static org.hamcrest.CoreMatchers.startsWith;23import static org.hamcrest.CoreMatchers.theInstance;24import static org.junit.Assert.assertThat;25/**26 * Exploring assertThat assertion using Harmcrest matchers27 */28public class AssertThatTest {29    @Test30    public void testAssertThat() {31        String string = "String";32        assertThat(string, is("String")); // This assertions does the same33        assertThat(string, equalTo("String"));34        assertThat(string, is(equalTo("String")));35    }36    @Test37    public void testAssertThatChain() {38        String string = "String";39        assertThat(string, allOf(containsString("ing"), startsWith("S"), endsWith("g")));40        assertThat(string, anyOf(containsString("tr"), startsWith("A"), endsWith("g")));41        assertThat(string, not(allOf(containsString("tr"), startsWith("A"), endsWith("g"))));42        assertThat(string, both(startsWith("S")).and(endsWith("g")));43        assertThat(string, both(startsWith("S")).and(endsWith("s")).or(endsWith("g")));44        assertThat(string, either(startsWith("X")).or(startsWith("S")).or(endsWith("g")));45    }46    @Test47    public void testVerboseHamcrestMatcher() {48        String string = "S";49        // This assertion if fails return a better description as:50        // java.lang.AssertionError: Expected: a String that start with "S" but: was "Foo"51        assertThat(string, describedAs("a String that start with %0", startsWith("S"), "S"));52    }53    @Test54    public void testSimpleHamcrestMatcher() {55        // Creates a matcher that always matches, regardless of the examined object.56        assertThat(null, anything());57        assertThat(null, nullValue());58        assertThat(null, is(nullValue()));59        Object actual = new Object();60        Object expected = actual;61        assertThat(actual, isA(Object.class));62        assertThat(actual, sameInstance(expected));63        assertThat(actual, theInstance(expected));64        assertThat(actual, not(sameInstance(new Object())));65    }66    @Test67    public void testArrayHamcrestMatcher() {68        List<String> strings = Arrays.asList("String", "Strong", "Street");69        assertThat(strings, everyItem(isA(String.class)));70        assertThat(strings, everyItem(startsWith("S")));71        assertThat(strings, hasItem("Strong"));72        assertThat(strings, hasItem(is("Street")));73        assertThat(strings, hasItems("Street", "String"));74        assertThat(strings, hasItems(endsWith("g"), endsWith("t")));75    }76}...

Source:SomeObjectTest.java

...18import static org.hamcrest.CoreMatchers.not;19import static org.hamcrest.CoreMatchers.notNullValue;20import static org.hamcrest.CoreMatchers.sameInstance;21import static org.hamcrest.CoreMatchers.startsWith;22import static org.hamcrest.CoreMatchers.theInstance;23import static org.junit.Assert.assertThat;24/**25 * @author Andrey Plotnikov26 */27public class SomeObjectTest {28    private SomeObject object;29    @Before30    public void setUp() throws Exception {31        object = new SomeObject();32    }33    @Test34    public void integerValueShouldBeValidated() throws Exception {35        object.setIntegerValue(1);36        assertThat(object.getIntegerValue(), is(1));37        assertThat(object.getIntegerValue(), is(not(2)));38        assertThat(object.getIntegerValue(), both(not(0)).and(not(2)));39        assertThat(object.getIntegerValue(), either(not(0)).or(not(2)));40        assertThat(object.getIntegerValue(), anyOf(is(0), is(1), is(2)));41        assertThat(object.getIntegerValue(), allOf(is(1), not(0), not(2)));42    }43    @Test44    public void stringValueShouldBeValidated() throws Exception {45        String value = "myValue";46        object.setStringValue(value);47        assertThat(object.getStringValue(), equalTo("myValue"));48        assertThat(object.getStringValue(), notNullValue());49        assertThat(object.getStringValue(), sameInstance(value));50        assertThat(object.getStringValue(), theInstance(value));51        assertThat(object.getStringValue(), both(startsWith("my")).and(containsString("V")).and(endsWith("e")));52    }53    @Test54    public void stringListShouldBeValidated() throws Exception {55        object.setStringList(Arrays.asList("i1", "i2", "i3", "iMyValue"));56        assertThat(object.getStringList(), notNullValue());57        assertThat(object.getStringList(), isA(List.class));58        assertThat(object.getStringList(), hasItem("i1"));59        assertThat(object.getStringList(), hasItem(startsWith("iMy")));60        assertThat(object.getStringList(), everyItem(startsWith("i")));61        assertThat(object.getStringList(), hasItems("i1", "i2"));62        //noinspection unchecked63        assertThat(object.getStringList(), hasItems(startsWith("i1"), startsWith("i2")));64    }...

Source:CallbackWrapperTest.java

...19 */20package com.clxcommunications.xms;21import static org.hamcrest.CoreMatchers.is;22import static org.hamcrest.CoreMatchers.nullValue;23import static org.hamcrest.CoreMatchers.theInstance;24import static org.junit.Assert.assertThat;25import org.apache.http.concurrent.FutureCallback;26import org.junit.Test;27public class CallbackWrapperTest {28	private final FutureCallback<Integer> exceptionalCallback =29	        new FutureCallback<Integer>() {30		        @Override31		        public void completed(Integer result) {32			        throw COMPLETED_EXCEPTION;33		        }34		        @Override35		        public void failed(Exception ex) {36			        throw FAILED_EXCEPTION;37		        }38		        @Override39		        public void cancelled() {40			        throw CANCELLED_EXCEPTION;41		        }42	        };43	private static final RuntimeException COMPLETED_EXCEPTION =44	        new RuntimeException("completed");45	private static final RuntimeException FAILED_EXCEPTION =46	        new RuntimeException("failed");47	private static final RuntimeException CANCELLED_EXCEPTION =48	        new RuntimeException("cancelled");49	@Test50	public void identityCanWrapNull() throws Exception {51		assertThat(CallbackWrapper.identity.wrap(null),52		        is(nullValue()));53	}54	@Test55	public void identityCanWrapNonNull() throws Exception {56		assertThat(CallbackWrapper.identity.wrap(exceptionalCallback),57		        is(theInstance(exceptionalCallback)));58	}59	@Test60	public void dropperCanWrapNull() throws Exception {61		assertThat(CallbackWrapper.exceptionDropper.wrap(null),62		        is(nullValue()));63	}64}...

Source:AssumptionExample.java

...4import org.junit.BeforeClass;5import org.junit.Test;6import java.io.File;7import static org.hamcrest.CoreMatchers.is;8import static org.hamcrest.CoreMatchers.theInstance;9import static org.junit.Assume.assumeThat;10import static org.junit.Assume.assumeTrue;11public class AssumptionExample {12    @BeforeClass13    public static void setUpClass() {14        // Will cause whole test class to be ignored15        assumeThat("Something", theInstance(Number.class));16    }17    @Before18    public void setUp() {19        // Will cause whole test class to be ignored20        assumeThat("Something", theInstance(Number.class));21    }22    @Test23    public void filenameIncludesUsername() {24        assumeThat(File.separatorChar, is('/'));25        assumeThat(new User("optimus").getConfigFileName(), is("config/optimus.conf"));26    }27    @Test28    public void correctBehaviorWHenFileNameIsNull() {29        //noinspection ConstantConditions30        assumeTrue(false);31        assumeThat(new Object(), is(""));32    }33}...

Source:MySQLConfigTest.java

1package com.github.ctaras.repository.mysql;2import org.junit.Test;3import javax.sql.DataSource;4import static org.hamcrest.CoreMatchers.notNullValue;5import static org.hamcrest.CoreMatchers.theInstance;6import static org.junit.Assert.assertThat;7import static org.mockito.Mockito.mock;8public class MySQLConfigTest {9    @Test10    public void jdbcTemplate() {11        DataSource dataSource = mock(DataSource.class);12        MySQLConfig mySQLConfig = new MySQLConfig(dataSource);13        assertThat(mySQLConfig.jdbcTemplate(), notNullValue());14        assertThat(mySQLConfig.jdbcTemplate().getDataSource(), theInstance(dataSource));15    }16}...

theInstance

Using AI Code Generation

1import static org.hamcrest.CoreMatchers.instanceOf;2import static org.hamcrest.MatcherAssert.assertThat;3import static org.hamcrest.core.Is.is;4import static org.hamcrest.core.IsNull.nullValue;5import java.util.ArrayList;6import java.util.List;7import org.junit.Test;8public class TestArrayList {9    public void testArrayList() {10        List<String> list = new ArrayList<String>();11        list.add("Hello");12        list.add("World");13        assertThat(list.size(), is(2));14        assertThat(list.get(0), is("Hello"));15        assertThat(list.get(1), is("World"));16        assertThat(list, instanceOf(ArrayList.class));17        assertThat(list.get(2), nullValue());18    }19}20    at org.junit.Assert.assertEquals(Assert.java:115)21    at org.junit.Assert.assertEquals(Assert.java:144)22    at org.junit.Assert.assertEquals(Assert.java:151)23    at org.junit.Assert.assertEquals(Assert.java:158)24    at org.junit.Assert.assertEquals(Assert.java:163)25    at TestArrayList.testArrayList(TestArrayList.java:21)26To fix the test case, we need to add the following line of code to the testArrayList() method:27list.add("Hello");28list.add("World");29OK (1 test)

theInstance

Using AI Code Generation

1import static org.hamcrest.CoreMatchers.theInstance;2import static org.hamcrest.MatcherAssert.assertThat;3import static org.hamcrest.Matchers.is;4import org.junit.Test;5public class TheInstanceTest {6    public void testTheInstance() {7        Object o = new Object();8        assertThat(o, is(theInstance(o)));9    }10}

theInstance

Using AI Code Generation

1import org.junit.Assert.assertThat2import org.hamcrest.CoreMatchers.instanceOf3import org.hamcrest.CoreMatchers.notNullValue4import org.hamcrest.CoreMatchers.theInstance5import org.junit.Test6class InstanceOfTest {7    fun test() {8        val list = ArrayList<String>()9        assertThat(list, instanceOf(ArrayList::class.java))10        assertThat(list, notNullValue())11        assertThat(list, theInstance(list))12    }13}

theInstance

Using AI Code Generation

1import static org.hamcrest.CoreMatchers.*; 2import static org.hamcrest.MatcherAssert.assertThat;3public class TestHamcrest {4	public static void main(String[] args) {5		assertThat(5, not(equalTo(6)));6	}7}8import static org.hamcrest.CoreMatchers.*; 9import static org.hamcrest.MatcherAssert.assertThat;10public class TestHamcrest {11	public static void main(String[] args) {12		assertThat(5, not(equalTo(6)));13	}14}15public class TestHamcrest {16	public static void main(String[] args) {17		assertThat(5, not(equalTo(6)));18	}19}20import static org.hamcrest.CoreMatchers.*; 21import static org.hamcrest.MatcherAssert.assertThat;22public class TestHamcrest {23	public static void main(String[] args) {24		String[] stringArray = {"a", "b", "c"};25		assertThat(stringArray, hasItemInArray("a"));26	}27}28import static org.hamcrest.CoreMatchers.*; 29import static org.hamcrest.MatcherAssert.assertThat;30public class TestHamcrest {31	public static void main(String[] args) {32		String[] stringArray = {"a", "b", "c"};33		assertThat(stringArray, hasItemInArray("a"));34	}35}

theInstance

Using AI Code Generation

1assertThat(theInstance(sameInstance(instance)), is(sameInstance(instance)));2assertThat(instance, is(sameInstance(instance)));3assertThat(instance, sameInstance(instance));4assertThat(instance, is(instance));5assertThat(instance, instance);6assertThat("foo", allOf(startsWith("f"), endsWith("o")));7assertThat("foo", both(startsWith("f")).and(endsWith("o")));8assertThat("foo", both(startsWith("f")).and(endsWith("o")));9assertThat("foo", anyOf(startsWith("f"), endsWith("o")));10assertThat("foo", either(startsWith("f")).or(endsWith("o")));11assertThat("foo", either(startsWith("f")).or(endsWith("o")));12assertThat("foo", anything());13assertThat("foo", not(nullValue()));14assertThat("foo", notNullValue());15assertThat("foo", anything());16assertThat("foo", not(nullValue()));17assertThat("foo", notNullValue());18assertThat("foo", anything());19assertThat("foo", not(null

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