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How to use CustomTypeSafeMatcher class of org.hamcrest package

Best junit code snippet using org.hamcrest.CustomTypeSafeMatcher

Source:HeaderMatchers.java

...18package org.w3.ldp.testsuite.matcher;19import java.util.regex.Pattern;20import org.apache.commons.lang3.StringUtils;21import org.hamcrest.BaseMatcher;22import org.hamcrest.CustomTypeSafeMatcher;23import org.hamcrest.Description;24import org.hamcrest.Matcher;25import org.jboss.resteasy.plugins.delegates.LinkDelegate;26import org.w3.ldp.testsuite.http.MediaTypes;27import javax.ws.rs.core.Link;28/**29 * Matcher collection to work with HttpHeaders.30 */31public class HeaderMatchers {32	private static final Pattern TURTLE_REGEX = Pattern.compile("^" + MediaTypes.TEXT_TURTLE + "\\s*(;|$)");33	/**34	 * Regular expression matching valid ETag values.35	 *36	 * @see <a href="http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.19">HTTP 1.1: Section 14.19 - ETag</a>37	 */38	public final static String ETAG_REGEX = "^(W/)?\"([^\"]|\\\\\")*\"$";39	public static Matcher<String> headerPresent() {40		return new BaseMatcher<String>() {41			@Override42			public boolean matches(Object item) {43				return item != null && StringUtils.isNotBlank(item.toString());44			}45			@Override46			public void describeTo(Description description) {47				description.appendText("set");48			}49		};50	}51	public static Matcher<String> headerNotPresent() {52		return new BaseMatcher<String>() {53			@Override54			public boolean matches(Object item) {55				return item == null || StringUtils.isBlank(item.toString());56			}57			@Override58			public void describeTo(Description description) {59				description.appendText("absent or empty");60			}61		};62	}63	public static Matcher<String> isLink(String uri, String rel) {64		final Link expected = Link.fromUri(uri).rel(rel).build();65		return new CustomTypeSafeMatcher<String>(String.format("a Link-Header to <%s> with rel='%s'", uri, rel)) {66			@Override67			protected boolean matchesSafely(String item) {68				return expected.equals(new LinkDelegate().fromString(item));69			}70		};71	}72	public static Matcher<String> isValidEntityTag() {73		return new CustomTypeSafeMatcher<String>("a valid EntityTag value as defined in RFC2616 section 14.19 (did you quote the value?)") {74			/**75			 * Checks that the ETag value is present and valid as defined in RFC261676			 *77			 * @param item78			 *			  the header value79			 * @return true only if the ETag is valid80			 *81			 * @see <a href="http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.19">HTTP 1.1: Section 14.19 - ETag</a>82			 */83			@Override84			protected boolean matchesSafely(String item) {85				return item.trim().matches(ETAG_REGEX);86			}87		};88	}89	/**90	 * Matcher testing a Content-Type response header's compatibility with91	 * JSON-LD (expects application/ld+json or application/json).92	 *93	 * @return the matcher94	 */95	public static Matcher<String> isJsonLdCompatibleContentType() {96		return new CustomTypeSafeMatcher<String>("application/ld+json or application/json") {97			@Override98			protected boolean matchesSafely(String item) {99				return item.equals(MediaTypes.APPLICATION_LD_JSON) || item.equals(MediaTypes.APPLICATION_JSON);100			}101		};102	}103	/**104	 * Matcher testing a Content-Type response header's compatibility with105	 * Turtle (expects text/turtle).106	 *107	 * @return the matcher108	 */109	public static Matcher<String> isTurtleCompatibleContentType() {110		return new CustomTypeSafeMatcher<String>("text/turtle") {111			@Override112			protected boolean matchesSafely(String item) {113				return MediaTypes.TEXT_TURTLE.equals(item)114						|| TURTLE_REGEX.matcher(item).find();115			}116		};117	}118}...

Source:IsThrowable.java

1package com.bluecatcode.hamcrest.matchers;2import org.hamcrest.CustomTypeSafeMatcher;3import org.hamcrest.Description;4import org.hamcrest.Factory;5import org.hamcrest.Matcher;6import static org.hamcrest.Matchers.allOf;7import static org.hamcrest.Matchers.is;8import static org.hamcrest.core.IsInstanceOf.instanceOf;9public class IsThrowable<T extends Throwable> extends CustomTypeSafeMatcher<T> {10    private final Matcher<T> matcher;11    public IsThrowable(Matcher<T> matcher) {12        super(CustomMatchers.fixedDescription(matcher));13        this.matcher = matcher;14    }15    @Override16    protected boolean matchesSafely(T item) {17        return matcher.matches(item);18    }19    public void describeMismatchSafely(T item, Description mismatchDescription) {20        matcher.describeMismatch(item, mismatchDescription);21    }22    /**23     * Matches if value is a Throwable of type <tt>type</tt>24     *25     * @param type throwable type26     * @param <T> the throwable type27     * @return the matcher28     */29    @Factory30    public static <T extends Throwable> Matcher<T> isThrowable(Class<?> type) {31        final Matcher<T> typeMatcher = instanceOf(type);32        return new IsThrowable<>(typeMatcher);33    }34    /**35     * Matches if value is a Throwable of type <tt>type</tt> that matches the <tt>matcher</tt>36     *37     * @param type    throwable type38     * @param matcher throwable matcher39     * @param <T> the throwable type40     * @return the matcher41     */42    @Factory43    public static <T extends Throwable> Matcher<T> isThrowable(Class<?> type, Matcher<? super T> matcher) {44        final Matcher<T> typeMatcher = instanceOf(type);45        return new IsThrowable<>(allOf(typeMatcher, matcher));46    }47    /**48     * Matches if value is a throwable with the <tt>message</tt>49     *50     * @param message message to match51     * @param <T> the throwable type52     * @return the matcher53     */54    @Factory55    public static <T extends Throwable> Matcher<T> withMessage(String message) {56        return withMessage(is(message));57    }58    /**59     * Matches if value is a throwable with a message that matches the <tt>matcher</tt>60     *61     * @param matcher message matcher62     * @param <T> the throwable type63     * @return the matcher64     */65    @Factory66    public static <T extends Throwable> Matcher<T> withMessage(final Matcher<String> matcher) {67        return new CustomTypeSafeMatcher<T>(CustomMatchers.fixedDescription("message ", matcher)) {68            @Override69            protected boolean matchesSafely(T item) {70                return matcher.matches(item.getMessage());71            }72            public void describeMismatchSafely(T item, Description mismatchDescription) {73                matcher.describeMismatch(item.getMessage(), mismatchDescription);74            }75        };76    }77    /**78     * Matches if value is a throwable with a cause that matches the <tt>matcher</tt>79     *80     * @param matcher cause matcher81     * @param <T> the throwable type82     * @param <C> the cause throwable type83     * @return the matcher84     */85    @Factory86    public static <T extends Throwable, C extends Throwable> Matcher<T> withCause(final Matcher<C> matcher) {87        return new CustomTypeSafeMatcher<T>(CustomMatchers.fixedDescription("cause ", matcher)) {88            @Override89            protected boolean matchesSafely(T item) {90                return matcher.matches(item.getCause());91            }92            public void describeMismatchSafely(T item, Description mismatchDescription) {93                matcher.describeMismatch(item.getCause(), mismatchDescription);94            }95        };96    }97}...

Source:CarHamcrestMatcher.java

1package com.kspichale.assert_playground.hamcrest;23import org.apache.commons.lang.builder.ToStringBuilder;4import org.hamcrest.CustomTypeSafeMatcher;5import org.hamcrest.Description;6import org.hamcrest.Factory;7import org.hamcrest.Matcher;8import org.hamcrest.TypeSafeMatcher;910import com.kspichale.assert_playground.model.Car;11import com.kspichale.assert_playground.model.EngineType;12import com.kspichale.assert_playground.model.Extra;1314public class CarHamcrestMatcher extends TypeSafeMatcher<Car> {1516	private Matcher<Car> matcher;1718	public CarHamcrestMatcher(Matcher<Car> matcher) {19		super();20		this.matcher = matcher;21	}2223	@Factory24	public static <T> Matcher<Car> hasExtras(Extra... extras) {25		Matcher<Car> matcher = new HasExtras(extras);26		return new CarHamcrestMatcher(matcher);27	}2829	@Factory30	public static CarHamcrestMatcher hasMinimumExtrasCount(int i) {31		Matcher<Car> matcher = new HasMinimumExtraCount(i);32		return new CarHamcrestMatcher(matcher);33	}3435	@Factory36	public static <T> Matcher<Car> hasEngineType(EngineType engineType) {37		Matcher<Car> matcher = new HasEngineType(engineType);38		return new CarHamcrestMatcher(matcher);39	}4041	@Override42	public void describeTo(Description desc) {43		this.matcher.describeTo(desc);44	}4546	@Override47	protected boolean matchesSafely(Car car) {48		return this.matcher.matches(car);49	}5051	private static class HasEngineType extends CustomTypeSafeMatcher<Car> {5253		private EngineType engineType;5455		public HasEngineType(EngineType engineType) {56			super("engine type is " + engineType);57			this.engineType = engineType;58		}5960		@Override61		protected boolean matchesSafely(Car car) {62			return car.getEngineType().equals(engineType);63		}64	}6566	private static class HasMinimumExtraCount extends CustomTypeSafeMatcher<Car> {6768		private int minimunExtraCount;6970		public HasMinimumExtraCount(int minimunExtraCount) {71			super("has at least " + minimunExtraCount + " extras");72			this.minimunExtraCount = minimunExtraCount;73		}7475		@Override76		protected boolean matchesSafely(Car car) {77			return car.getExtras().size() >= minimunExtraCount;78		}79	}8081	private static class HasExtras extends CustomTypeSafeMatcher<Car> {8283		private Extra[] extras;8485		public HasExtras(Extra... extras) {86			super("has extras " + ToStringBuilder.reflectionToString(extras));87			this.extras = extras;88		}8990		@Override91		protected boolean matchesSafely(Car car) {92			if (car.getExtras().size() != extras.length) {93				return false;94			}95			for (Extra extra : extras) {
...

Source:DockerMatchers.java

2import com.github.dockerjava.api.command.InspectContainerResponse;3import com.github.dockerjava.api.model.Volume;4import com.github.dockerjava.core.DockerRule;5import com.github.dockerjava.core.RemoteApiVersion;6import org.hamcrest.CustomTypeSafeMatcher;7import org.hamcrest.Description;8import org.hamcrest.FeatureMatcher;9import org.hamcrest.Matcher;10import java.util.ArrayList;11import java.util.List;12import static com.github.dockerjava.utils.TestUtils.getVersion;13/**14 * @author Kanstantsin Shautsou15 */16public class DockerMatchers {17    private DockerMatchers() {18    }19    public static MountedVolumes mountedVolumes(Matcher<? super List<Volume>> subMatcher) {20        return new MountedVolumes(subMatcher, "Mounted volumes", "mountedVolumes");21    }22    public static class MountedVolumes extends FeatureMatcher<InspectContainerResponse, List<Volume>> {23        public MountedVolumes(Matcher<? super List<Volume>> subMatcher, String featureDescription, String featureName) {24            super(subMatcher, featureDescription, featureName);25        }26        @Override27        public List<Volume> featureValueOf(InspectContainerResponse item) {28            List<Volume> volumes = new ArrayList<>();29            for (InspectContainerResponse.Mount mount : item.getMounts()) {30                volumes.add(mount.getDestination());31            }32            return volumes;33        }34    }35    public static Matcher<DockerRule> apiVersionGreater(final RemoteApiVersion version) {36        return new CustomTypeSafeMatcher<DockerRule>("is greater") {37            public boolean matchesSafely(DockerRule dockerRule) {38                return getVersion(dockerRule.getClient()).isGreater(version);39            }40        };41    }42    public static Matcher<DockerRule> isGreaterOrEqual(final RemoteApiVersion version) {43        return new CustomTypeSafeMatcher<DockerRule>("is greater or equal") {44            public boolean matchesSafely(DockerRule dockerRule) {45                return getVersion(dockerRule.getClient()).isGreaterOrEqual(version);46            }47            @Override48            protected void describeMismatchSafely(DockerRule rule, Description mismatchDescription) {49                mismatchDescription50                        .appendText(" was ")51                        .appendText(getVersion(rule.getClient()).toString());52            }53        };54    }55}...

Source:CustomViewMatchers.java

...8public final class CustomViewMatchers {9    private CustomViewMatchers() {10    }11    public static Matcher<View> withValueEqualToTextView(final int viewId) {12        return CustomTypeSafeMatcher.create(viewId);13    }14    public static Matcher<View> withDigitsOnlyEqualsToTextView(final int viewId) {15        return CustomTypeSafeMatcher.createForDigits(viewId);16    }17    static final class CustomTypeSafeMatcher extends TypeSafeMatcher<View> {18        private static final String EXTRACT_DIGITS_REGEX = "\\D+";19        private final boolean shouldExtractDigits;20        @IdRes private final int viewId;21        /* default */ static CustomTypeSafeMatcher create(@IdRes final int viewId) {22            return new CustomTypeSafeMatcher(viewId, false);23        }24        /* default */ static CustomTypeSafeMatcher createForDigits(@IdRes final int viewId) {25            return new CustomTypeSafeMatcher(viewId, true);26        }27        private CustomTypeSafeMatcher(@IdRes final int viewId, final boolean shouldExtractDigits) {28            this.viewId = viewId;29            this.shouldExtractDigits = shouldExtractDigits;30        }31        @Override32        public void describeTo(final Description description) {33            description.appendText("Has EditText/TextView the value equals to view:  " + viewId);34        }35        @Override36        public boolean matchesSafely(final View view) {37            final View viewById = view.getRootView().findViewById(viewId);38            if (!(view instanceof TextView || !(viewById instanceof TextView))) {39                return false;40            }41            //noinspection ConstantConditions...

Source:DriveThruMatcher.java

1package vehiclesurvey;2import org.hamcrest.CustomTypeSafeMatcher;3import org.hamcrest.Matcher;4import org.hamcrest.core.AllOf;5import vehiclesurvey.time.Time;6import java.util.ArrayList;7import java.util.Collection;8import static java.lang.Math.abs;9import static vehiclesurvey.time.Time.time;10/*11* A fluent interface for matchers someDriveThru().atTime(1234).withSpeed(62.1).....12* */13public class DriveThruMatcher extends CustomTypeSafeMatcher<DriveThru> {14    private Collection<Matcher<DriveThru>> matchers;15    public DriveThruMatcher() {16        super("Composite matcher");17        matchers = new ArrayList<Matcher<DriveThru>>();18    }19    @Override20    protected boolean matchesSafely(DriveThru item) {21        return new AllOf(matchers).matches(item);22    }23    public static DriveThruMatcher someDriveThru() {24        return new DriveThruMatcher();25    }26    public DriveThruMatcher atTime(int timeStamp) {27        final Time time = time(timeStamp);28        matchers.add(new CustomTypeSafeMatcher<DriveThru>("Expected drive through with time: " + time) {29            @Override30            protected boolean matchesSafely(DriveThru item) {31                return time.equals(item.time);32            }33        });34        return this;35    }36    public DriveThruMatcher onDay(final int day) {37        matchers.add(new CustomTypeSafeMatcher<DriveThru>("Expected drive through on day: " + day) {38            @Override39            protected boolean matchesSafely(DriveThru item) {40                return item.day == day;41            }42        });43        return this;44    }45    public DriveThruMatcher withSpeed(final double speed) {46        matchers.add(new CustomTypeSafeMatcher<DriveThru>("Expected drive through with speed: " + speed) {47            @Override48            protected boolean matchesSafely(DriveThru item) {49                return abs(item.speed - speed) < .01;50            }51        });52        return this;53    }54}...

Source:VibratoMatchers.java

1package vibrato.testtools;2import org.hamcrest.CustomTypeSafeMatcher;3import org.hamcrest.Matcher;4import vibrato.complex.Complex;5import vibrato.complex.ComplexNumber;6public class VibratoMatchers {7    private static final double precision = 1 / (double) (1 << 24);8    public static Matcher<Double> approximatelyEqualTo(double expectedValue) {9        double acceptableError = Math.abs(expectedValue) <= precision ? precision * precision : Math.abs(expectedValue) * precision;10        double min = expectedValue - acceptableError;11        double max = expectedValue + acceptableError;12        return new CustomTypeSafeMatcher<Double>("Equal to " + expectedValue + " +/- " + acceptableError) {13            @Override14            protected boolean matchesSafely(Double actualValue) {15                return actualValue != null && min <= actualValue && actualValue <= max;16            }17        };18    }19    public static <T extends Complex<?>> Matcher<T> approximatelyEqualTo(T expectedValue) {20        ComplexNumber expectedComplexValue = ComplexNumber.createRI(expectedValue.real(), expectedValue.imaginary());21        double acceptableError = expectedComplexValue.length() <= precision ? precision * precision : expectedComplexValue.length() * precision;22        return new CustomTypeSafeMatcher<T>("Equal to " + expectedComplexValue.toRIString() + " +/- " + acceptableError) {23            @Override24            protected boolean matchesSafely(T actualValue) {25                double error = actualValue != null ? expectedComplexValue.minus(actualValue).length() : Double.MAX_VALUE;26                return error <= acceptableError;27            }28        };29    }30}...

Source:CustomTypeSafeMatcher.java

...19/*    */ 20/*    */ 21/*    */ 22/*    */ 23/*    */ public abstract class CustomTypeSafeMatcher<T>24/*    */   extends TypeSafeMatcher<T>25/*    */ {26/*    */   private final String fixedDescription;27/*    */   28/*    */   public CustomTypeSafeMatcher(String description) {29/* 29 */     if (description == null) {30/* 30 */       throw new IllegalArgumentException("Description must be non null!");31/*    */     }32/* 32 */     this.fixedDescription = description;33/*    */   }34/*    */ 35/*    */   36/*    */   public final void describeTo(Description description) {37/* 37 */     description.appendText(this.fixedDescription);38/*    */   }39/*    */ }40/* Location:              C:\Users\CAR\Desktop\sab\SAB_projekat_1920\SAB_projekat_1920\SAB_projekat_1920.jar!\org\hamcrest\CustomTypeSafeMatcher.class41 * Java compiler version: 5 (49.0)42 * JD-Core Version:       1.1.343 */...

CustomTypeSafeMatcher

Using AI Code Generation

1import static org.hamcrest.MatcherAssert.assertThat;2import static org.hamcrest.Matchers.equalTo;3import static org.hamcrest.Matchers.is;4import java.util.ArrayList;5import java.util.List;6import org.hamcrest.Description;7import org.hamcrest.Matcher;8import org.hamcrest.TypeSafeMatcher;9import org.junit.Test;10public class CustomTypeSafeMatcher {11    public void testCustomTypeSafeMatcher() {12        List<Integer> list = new ArrayList<Integer>();13        list.add(1);14        list.add(2);15        list.add(3);16        list.add(4);17        list.add(5);18        assertThat(list, is(new CustomListMatcher<Integer>(equalTo(3))));19    }20}21class CustomListMatcher<T> extends TypeSafeMatcher<List<T>> {22    private final Matcher<T> matcher;23    public CustomListMatcher(Matcher<T> matcher) {24        this.matcher = matcher;25    }26    public void describeTo(Description description) {27        description.appendText("list containing ").appendDescriptionOf(matcher);28    }29    protected boolean matchesSafely(List<T> item) {30        for (T element : item) {31            if (matcher.matches(element)) {32                return true;33            }34        }35        return false;36    }37}38Related posts: How to use Custom Hamcrest Matcher in JUnit Test? JUnit Test for Custom Exception JUnit Test for Custom Exception with @Test(expected = Exception.class) JUnit Test for Custom Exception with @Rule ExpectedException JUnit Test for Custom Exception with ExpectedException Rule JUnit Test for Custom Exception with ExpectedException Rule

CustomTypeSafeMatcher

Using AI Code Generation

1import org.hamcrest.Description;2import org.hamcrest.Factory;3import org.hamcrest.Matcher;4import org.hamcrest.TypeSafeMatcher;5public class CustomTypeSafeMatcher<T> extends TypeSafeMatcher<T> {6    private final T expectedValue;7    private String expectedValueDescription;8    public CustomTypeSafeMatcher(T expectedValue) {9        this.expectedValue = expectedValue;10    }11    public CustomTypeSafeMatcher(T expectedValue, String expectedValueDescription) {12        this.expectedValue = expectedValue;13        this.expectedValueDescription = expectedValueDescription;14    }15    protected boolean matchesSafely(T actualValue) {16        return expectedValue.equals(actualValue);17    }18    public void describeTo(Description description) {19        description.appendText("value should be " + expectedValue);20        if (expectedValueDescription != null) {21            description.appendText(" (" + expectedValueDescription + ")");22        }23    }24    public static <T> Matcher<T> isValue(T expectedValue) {25        return new CustomTypeSafeMatcher<T>(expectedValue);26    }27    public static <T> Matcher<T> isValue(T expectedValue, String expectedValueDescription) {28        return new CustomTypeSafeMatcher<T>(expectedValue, expectedValueDescription);29    }30}31public class CustomTypeSafeMatcherTest {32    public void testCustomTypeSafeMatcher() {33        assertThat("Hello", isValue("Hello"));34        assertThat("Hello", isValue("Hello", "Hello World"));35    }36}37org.junit.ComparisonFailure: value should be Hello (Hello World) expected:<[Hello]> but was:<[World]>38    at org.junit.Assert.assertEquals(Assert.java:115)39    at org.junit.Assert.assertEquals(Assert.java:144)40    at org.hamcrest.MatcherAssert.assertThat(MatcherAssert.java:20)41    at org.hamcrest.MatcherAssert.assertThat(MatcherAssert.java:8)42    at org.codejava.junit.CustomTypeSafeMatcherTest.testCustomTypeSafeMatcher(CustomTypeSafeMatcherTest.java:19)43The describeTo() method

CustomTypeSafeMatcher

Using AI Code Generation

1import org.hamcrest.CustomTypeSafeMatcher;2import org.hamcrest.Matcher;3import org.hamcrest.Description;4public class CustomMatcherExample extends CustomTypeSafeMatcher<String> {5    public CustomMatcherExample(String expected) {6        super(expected);7    }8    protected boolean matchesSafely(String actual) {9        return actual.equals(expected);10    }11    public void describeTo(Description description) {12        description.appendText("Expected value is: " + expected);13    }14    public static Matcher<String> isValue(String expected) {15        return new CustomMatcherExample(expected);16    }17}18import org.hamcrest.CustomMatcher;19import org.hamcrest.Description;20public class CustomMatcherExample extends CustomMatcher<String> {21    private String expected;22    public CustomMatcherExample(final String expected) {23        super("Expected value is: " + expected);24        this.expected = expected;25    }26    public boolean matches(Object actual) {27        return actual.equals(expected);28    }29    public void describeTo(Description description) {30        description.appendText("Expected value is: " + expected);31    }32}33import org.hamcrest.CustomMatcher;34import org.hamcrest.Description;35public class CustomMatcherExample extends CustomMatcher<String> {36    private String expected;37    public CustomMatcherExample(final String expected) {38        super("Expected value is: " + expected);39        this.expected = expected;40    }41    public boolean matches(Object actual) {42        return actual.equals(expected);43    }44    public void describeTo(Description description) {45        description.appendText("Expected value is: " + expected);46    }47}48import org.hamcrest.CustomMatcher;49import org.hamcrest.Description;50public class CustomMatcherExample extends CustomMatcher<String> {51    private String expected;52    public CustomMatcherExample(final String expected) {53        super("Expected value is: " + expected);54        this.expected = expected;55    }56    public boolean matches(Object actual) {57        return actual.equals(expected);58    }59    public void describeTo(Description description) {60        description.appendText("Expected value is: " + expected);61    }62}63import org.hamcrest.CustomMatcher;64import org.hamcrest.Description;

CustomTypeSafeMatcher

Using AI Code Generation

1public class CustomTypeSafeMatcher extends TypeSafeMatcher {2    private String expected;3    public CustomTypeSafeMatcher(String expected) {4        this.expected = expected;5    }6    protected boolean matchesSafely(Object actual) {7        return expected.equals(actual);8    }9    public void describeTo(Description description) {10        description.appendText("expected: " + expected);11    }12    protected void describeMismatchSafely(Object item, Description mismatchDescription) {13        mismatchDescription.appendText("was: " + item);14    }15}16public class CustomBaseMatcher extends BaseMatcher {17    private String expected;18    public CustomBaseMatcher(String expected) {19        this.expected = expected;20    }21    public boolean matches(Object actual) {22        return expected.equals(actual);23    }24    public void describeTo(Description description) {25        description.appendText("expected: " + expected);26    }27    public void describeMismatch(Object item, Description mismatchDescription) {28        mismatchDescription.appendText("was: " + item);29    }30}31public class CustomMatcherTest {32    public void testTypeSafeMatcher() {33        assertThat("Hello World", new CustomTypeSafeMatcher("Hello World"));34    }35    public void testBaseMatcher() {36        assertThat("Hello World", new CustomBaseMatcher("Hello World"));37    }38}39    at org.junit.Assert.assertEquals(Assert.java:115)40    at org.junit.Assert.assertEquals(Assert.java:144)41    at org.hamcrest.MatcherAssert.assertThat(MatcherAssert.java:20)42    at org.hamcrest.MatcherAssert.assertThat(MatcherAssert.java:8)43    at com.vogella.junit.first.CustomMatcherTest.testTypeSafeMatcher(CustomMatcherTest.java:19)44    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)45    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)46    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)47    at java.lang.reflect.Method.invoke(Method.java:498)

CustomTypeSafeMatcher

Using AI Code Generation

1import org.hamcrest.BaseMatcher;2import org.hamcrest.Description;3import org.hamcrest.Matcher;4import org.hamcrest.TypeSafeMatcher;5import java.util.List;6public class CustomTypeSafeMatcher {7    public static Matcher<List> hasSize(final int size) {8        return new TypeSafeMatcher<List>() {9            public boolean matchesSafely(List list) {10                return list.size() == size;11            }12            public void describeTo(Description description) {13                description.appendText("List size should be ").appendValue(size);14            }15        };16    }17    public static Matcher<String> containsString(final String substring) {18        return new BaseMatcher<String>() {19            public boolean matches(Object item) {20                return item.toString().contains(substring);21            }22            public void describeTo(Description description) {23                description.appendText("String should contain ").appendValue(substring);24            }25        };26    }27}28import org.hamcrest.Matcher;29import org.junit.Test;30import java.util.Arrays;31import java.util.List;32import static org.hamcrest.CoreMatchers.containsString;33import static org.hamcrest.CoreMatchers.is;34import static org.hamcrest.MatcherAssert.assertThat;35import static org.hamcrest.Matchers.hasSize;36public class CustomTypeSafeMatcherTest {37    public void testCustomTypeSafeMatcher() {38        List<String> list = Arrays.asList("one", "two", "three");39        assertThat(list, hasSize(3));40        assertThat(list, hasSize(is(3)));41        assertThat(list, hasSize(Matchers.is(3)));42        assertThat("one two three", containsString("one"));43        assertThat("one two three", containsString(Matchers.is("one")));44    }45}

Source: Hamcrest Matcher compilation difference between Eclipse and javac

1public static String streamToString(final InputStream inputStream) throws Exception {2    // buffering optional3    try4    (5        final BufferedReader br6           = new BufferedReader(new InputStreamReader(inputStream))7    ) {8        // parallel optional9        return br.lines().parallel().collect(Collectors.joining("\n"));10    } catch (final IOException e) {11        throw new RuntimeException(e);12        // whatever.13    }14}15

Source:Hamcrest Matcher compilation difference between Eclipse and javac

public static String streamToString(final InputStream inputStream) throws Exception {
    // buffering optional
    try
    (
        final BufferedReader br
           = new BufferedReader(new InputStreamReader(inputStream))
    ) {
        // parallel optional
        return br.lines().parallel().collect(Collectors.joining("\n"));
    } catch (final IOException e) {
        throw new RuntimeException(e);
        // whatever.
    }
}

JUnit Tutorial:

LambdaTest also has a detailed JUnit tutorial explaining its features, importance, advanced use cases, best practices, and more to help you get started with running your automation testing scripts.

JUnit Tutorial Chapters:

Here are the detailed JUnit testing chapters to help you get started:

Importance of Unit testing - Learn why Unit testing is essential during the development phase to identify bugs and errors.
Top Java Unit testing frameworks - Here are the upcoming JUnit automation testing frameworks that you can use in 2023 to boost your unit testing.
What is the JUnit framework
Why is JUnit testing important - Learn the importance and numerous benefits of using the JUnit testing framework.
Features of JUnit - Learn about the numerous features of JUnit and why developers prefer it.
JUnit 5 vs. JUnit 4: Differences - Here is a complete comparison between JUnit 5 and JUnit 4 testing frameworks.
Setting up the JUnit environment - Learn how to set up your JUnit testing environment.
Getting started with JUnit testing - After successfully setting up your JUnit environment, this chapter will help you get started with JUnit testing in no time.
Parallel testing with JUnit - Parallel Testing can be used to reduce test execution time and improve test efficiency. Learn how to perform parallel testing with JUnit.
Annotations in JUnit - When writing automation scripts with JUnit, we can use JUnit annotations to specify the type of methods in our test code. This helps us identify those methods when we run JUnit tests using Selenium WebDriver. Learn in detail what annotations are in JUnit.
Assertions in JUnit - Assertions are used to validate or test that the result of an action/functionality is the same as expected. Learn in detail what assertions are and how to use them while performing JUnit testing.
Parameterization in JUnit - Parameterized Test enables you to run the same automated test scripts with different variables. By collecting data on each method's test parameters, you can minimize time spent on writing tests. Learn how to use parameterization in JUnit.
Nested Tests In JUnit 5 - A nested class is a non-static class contained within another class in a hierarchical structure. It can share the state and setup of the outer class. Learn about nested annotations in JUnit 5 with examples.
Best practices for JUnit testing - Learn about the best practices, such as always testing key methods and classes, integrating JUnit tests with your build, and more to get the best possible results.
Advanced Use Cases for JUnit testing - Take a deep dive into the advanced use cases, such as how to run JUnit tests in Jupiter, how to use JUnit 5 Mockito for Unit testing, and more for JUnit testing.