How to use Preconditions class of org.assertj.core.util package

Best Assertj code snippet using org.assertj.core.util.Preconditions

Source:Events.java

...28import org.assertj.core.api.Condition;29import org.assertj.core.api.ListAssert;30import org.assertj.core.api.SoftAssertions;31import org.assertj.core.data.Index;32import org.junit.platform.commons.util.Preconditions;33import org.junit.platform.engine.TestExecutionResult;34import org.junit.platform.engine.TestExecutionResult.Status;35/**36 * {@code Events} is a facade that provides a fluent API for working with37 * {@linkplain Event events}.38 *39 * @since 1.440 */41@API(status = EXPERIMENTAL, since = "1.4")42public final class Events {43	private final List<Event> events;44	private final String category;45	Events(Stream<Event> events, String category) {46		this(Preconditions.notNull(events, "Event stream must not be null").collect(toList()), category);47	}48	Events(List<Event> events, String category) {49		Preconditions.notNull(events, "Event list must not be null");50		Preconditions.containsNoNullElements(events, "Event list must not contain null elements");51		this.events = Collections.unmodifiableList(events);52		this.category = category;53	}54	String getCategory() {55		return this.category;56	}57	// --- Accessors -----------------------------------------------------------58	/**59	 * Get the {@linkplain Event events} as a {@link List}.60	 *61	 * @return the list of events; never {@code null}62	 * @see #stream()63	 */64	public List<Event> list() {65		return this.events;66	}67	/**68	 * Get the {@linkplain Event events} as a {@link Stream}.69	 *70	 * @return the stream of events; never {@code null}71	 * @see #list()72	 */73	public Stream<Event> stream() {74		return this.events.stream();75	}76	/**77	 * Shortcut for {@code events.stream().map(mapper)}.78	 *79	 * @param mapper a {@code Function} to apply to each event; never {@code null}80	 * @return the mapped stream of events; never {@code null}81	 * @see #stream()82	 * @see Stream#map(Function)83	 */84	public <R> Stream<R> map(Function<? super Event, ? extends R> mapper) {85		Preconditions.notNull(mapper, "Mapping function must not be null");86		return stream().map(mapper);87	}88	/**89	 * Shortcut for {@code events.stream().filter(predicate)}.90	 *91	 * @param predicate a {@code Predicate} to apply to each event to decide if92	 * it should be included in the filtered stream; never {@code null}93	 * @return the filtered stream of events; never {@code null}94	 * @see #stream()95	 * @see Stream#filter(Predicate)96	 */97	public Stream<Event> filter(Predicate<? super Event> predicate) {98		Preconditions.notNull(predicate, "Filter predicate must not be null");99		return stream().filter(predicate);100	}101	/**102	 * Get the {@link Executions} for the current set of {@linkplain Event events}.103	 *104	 * @return an instance of {@code Executions} for the current set of events;105	 * never {@code null}106	 */107	public Executions executions() {108		return new Executions(this.events, this.category);109	}110	// --- Statistics ----------------------------------------------------------111	/**112	 * Get the number of {@linkplain Event events} contained in this {@code Events}113	 * object.114	 */115	public long count() {116		return this.events.size();117	}118	// --- Built-in Filters ----------------------------------------------------119	/**120	 * Get the skipped {@link Events} contained in this {@code Events} object.121	 *122	 * @return the filtered {@code Events}; never {@code null}123	 */124	public Events skipped() {125		return new Events(eventsByType(EventType.SKIPPED), this.category + " Skipped");126	}127	/**128	 * Get the started {@link Events} contained in this {@code Events} object.129	 *130	 * @return the filtered {@code Events}; never {@code null}131	 */132	public Events started() {133		return new Events(eventsByType(EventType.STARTED), this.category + " Started");134	}135	/**136	 * Get the finished {@link Events} contained in this {@code Events} object.137	 *138	 * @return the filtered {@code Events}; never {@code null}139	 */140	public Events finished() {141		return new Events(eventsByType(EventType.FINISHED), this.category + " Finished");142	}143	/**144	 * Get the aborted {@link Events} contained in this {@code Events} object.145	 *146	 * @return the filtered {@code Events}; never {@code null}147	 */148	public Events aborted() {149		return new Events(finishedEventsByStatus(Status.ABORTED), this.category + " Aborted");150	}151	/**152	 * Get the succeeded {@link Events} contained in this {@code Events} object.153	 *154	 * @return the filtered {@code Events}; never {@code null}155	 */156	public Events succeeded() {157		return new Events(finishedEventsByStatus(Status.SUCCESSFUL), this.category + " Successful");158	}159	/**160	 * Get the failed {@link Events} contained in this {@code Events} object.161	 *162	 * @return the filtered {@code Events}; never {@code null}163	 */164	public Events failed() {165		return new Events(finishedEventsByStatus(Status.FAILED), this.category + " Failed");166	}167	/**168	 * Get the reporting entry publication {@link Events} contained in this169	 * {@code Events} object.170	 *171	 * @return the filtered {@code Events}; never {@code null}172	 */173	public Events reportingEntryPublished() {174		return new Events(eventsByType(EventType.REPORTING_ENTRY_PUBLISHED),175			this.category + " Reporting Entry Published");176	}177	/**178	 * Get the dynamic registration {@link Events} contained in this179	 * {@code Events} object.180	 *181	 * @return the filtered {@code Events}; never {@code null}182	 */183	public Events dynamicallyRegistered() {184		return new Events(eventsByType(EventType.DYNAMIC_TEST_REGISTERED), this.category + " Dynamically Registered");185	}186	// --- Assertions ----------------------------------------------------------187	/**188	 * Assert statistics for the {@linkplain Event events} contained in this189	 * {@code Events} object.190	 *191	 * <h4>Example</h4>192	 *193	 * <p>{@code events.assertStatistics(stats -> stats.started(1).succeeded(1).failed(0));}194	 *195	 * @param statisticsConsumer a {@link Consumer} of {@link EventStatistics};196	 * never {@code null}197	 * @return this {@code Events} object for method chaining; never {@code null}198	 */199	public Events assertStatistics(Consumer<EventStatistics> statisticsConsumer) {200		Preconditions.notNull(statisticsConsumer, "Consumer must not be null");201		EventStatistics eventStatistics = new EventStatistics(this, this.category);202		statisticsConsumer.accept(eventStatistics);203		eventStatistics.assertAll();204		return this;205	}206	/**207	 * Assert that all {@linkplain Event events} contained in this {@code Events}208	 * object exactly match the provided conditions.209	 *210	 * <p>Conditions can be imported statically from {@link EventConditions}211	 * and {@link TestExecutionResultConditions}.212	 *213	 * <h4>Example</h4>214	 *215	 * <pre class="code">216	 * executionResults.tests().assertEventsMatchExactly(217	 *     event(test("exampleTestMethod"), started()),218	 *     event(test("exampleTestMethod"), finishedSuccessfully())219	 * );220	 * </pre>221	 *222	 * @param conditions the conditions to match against; never {@code null}223	 * @see EventConditions224	 * @see TestExecutionResultConditions225	 */226	@SafeVarargs227	public final void assertEventsMatchExactly(Condition<? super Event>... conditions) {228		Preconditions.notNull(conditions, "conditions must not be null");229		assertEventsMatchExactly(this.events, conditions);230	}231	/**232	 * Shortcut for {@code org.assertj.core.api.Assertions.assertThat(events.list())}.233	 *234	 * @return an instance of {@link ListAssert} for events; never {@code null}235	 * @see org.assertj.core.api.Assertions#assertThat(List)236	 * @see org.assertj.core.api.ListAssert237	 */238	public ListAssert<Event> assertThatEvents() {239		return org.assertj.core.api.Assertions.assertThat(list());240	}241	// --- Diagnostics ---------------------------------------------------------242	/**243	 * Print all events to {@link System#out}.244	 *245	 * @return this {@code Events} object for method chaining; never {@code null}246	 */247	public Events debug() {248		debug(System.out);249		return this;250	}251	/**252	 * Print all events to the supplied {@link OutputStream}.253	 *254	 * @param out the {@code OutputStream} to print to; never {@code null}255	 * @return this {@code Events} object for method chaining; never {@code null}256	 */257	public Events debug(OutputStream out) {258		Preconditions.notNull(out, "OutputStream must not be null");259		debug(new PrintWriter(out, true));260		return this;261	}262	/**263	 * Print all events to the supplied {@link Writer}.264	 *265	 * @param writer the {@code Writer} to print to; never {@code null}266	 * @return this {@code Events} object for method chaining; never {@code null}267	 */268	public Events debug(Writer writer) {269		Preconditions.notNull(writer, "Writer must not be null");270		debug(new PrintWriter(writer, true));271		return this;272	}273	private Events debug(PrintWriter printWriter) {274		printWriter.println(this.category + " Events:");275		this.events.forEach(event -> printWriter.printf("\t%s%n", event));276		return this;277	}278	// --- Internals -----------------------------------------------------------279	private Stream<Event> eventsByType(EventType type) {280		Preconditions.notNull(type, "EventType must not be null");281		return stream().filter(byType(type));282	}283	private Stream<Event> finishedEventsByStatus(Status status) {284		Preconditions.notNull(status, "Status must not be null");285		return eventsByType(EventType.FINISHED)//286				.filter(byPayload(TestExecutionResult.class, where(TestExecutionResult::getStatus, isEqual(status))));287	}288	@SafeVarargs289	private static void assertEventsMatchExactly(List<Event> events, Condition<? super Event>... conditions) {290		Assertions.assertThat(events).hasSize(conditions.length);291		SoftAssertions softly = new SoftAssertions();292		for (int i = 0; i < conditions.length; i++) {293			softly.assertThat(events).has(conditions[i], Index.atIndex(i));294		}295		softly.assertAll();296	}297}...

Preconditions

Using AI Code Generation

1import org.assertj.core.util.Preconditions;2import org.junit.Test;3import static org.assertj.core.api.Assertions.assertThat;4import static org.assertj.core.api.Assertions.assertThatThrownBy;5public class PreconditionsTest {6    public void shouldThrowExceptionWhenNull() {7        assertThatThrownBy(() -> Preconditions.checkNotNull(null, "message"))8                .isInstanceOf(NullPointerException.class)9                .hasMessage("message");10    }11    public void shouldReturnSameObjectWhenNotNull() {12        assertThat(Preconditions.checkNotNull("test", "message")).isEqualTo("test");13    }14}15    at org.junit.Assert.assertEquals(Assert.java:115)16    at org.junit.Assert.assertEquals(Assert.java:144)17    at org.assertj.core.api.AbstractThrowableAssert.hasMessage(AbstractThrowableAssert.java:188)18    at org.assertj.core.api.Assertions.assertThatThrownBy(Assertions.java:1552)19    at org.assertj.core.api.Assertions.assertThatThrownBy(Assertions.java:1520)20    at org.assertj.core.util.PreconditionsTest.shouldThrowExceptionWhenNull(PreconditionsTest.java:17)

Preconditions

Using AI Code Generation

1import org.assertj.core.util.Preconditions;2import org.junit.Test;3import static org.assertj.core.api.Assertions.assertThat;4public class PreconditionsTest {5    public void shouldThrowExceptionWhenConditionIsFalse() {6        try {7            Preconditions.checkArgument(1 == 2, "Condition is false");8        } catch (IllegalArgumentException e) {9            assertThat(e.getMessage()).isEqualTo("Condition is false");10        }11    }12}

Preconditions

Using AI Code Generation

1import static org.assertj.core.util.Preconditions.*;2public void testPreconditions() {3  String s = "Hello";4  checkNotNull(s);5}6import static com.google.common.base.Preconditions.*;7public void testPreconditions() {8  String s = "Hello";9  checkNotNull(s);10}11import static org.apache.commons.lang3.Validate.*;12public void testPreconditions() {13  String s = "Hello";14  notNull(s);15}16import static org.apache.commons.lang.Validate.*;17public void testPreconditions() {18  String s = "Hello";19  notNull(s);20}21import static org.springframework.util.Assert.*;22public void testPreconditions() {23  String s = "Hello";24  notNull(s);25}26import static org.apache.commons.lang.Validate.*;27public void testPreconditions() {28  String s = "Hello";29  notNull(s);30}31import static org.apache.commons.lang.Validate.*;32public void testPreconditions() {33  String s = "Hello";34  notNull(s);35}36import static org.apache.commons.lang.Validate.*;37public void testPreconditions() {38  String s = "Hello";39  notNull(s);40}41import static org.apache.commons.lang.Validate.*;42public void testPreconditions() {43  String s = "Hello";44  notNull(s);45}46import static org.apache.commons.lang.Validate.*;47public void testPreconditions() {48  String s = "Hello";49  notNull(s);50}51import static org.apache.commons.lang.Validate.*;52public void testPreconditions() {53  String s = "Hello";54  notNull(s);55}56import static org.apache.commons.lang.Validate.*;57public void testPreconditions() {58  String s = "Hello";59  notNull(s);60}61import static org.apache

Preconditions

Using AI Code Generation

1import org.assertj.core.api.Assertions;2import org.assertj.core.util.Preconditions;3public class AssertionDemo {4	public static void main(String[] args) {5		String name = "Ram";6		String address = "Kathmandu";7		int age = 30;8		Preconditions.checkNotNull(name, "Name should not be null");9		Preconditions.checkNotNull(address, "Address should not be null");10		Preconditions.checkArgument(age > 0, "Age should be greater than 0");11		Assertions.assertThat(name).isNotNull();12		Assertions.assertThat(address).isNotNull();13		Assertions.assertThat(age).isGreaterThan(0);14	}15}16                Preconditions.checkArgument(age > 0, "Age should be greater than 0");17  found   : @IntVal(30) int18  required: @LessThan("0") int19                Preconditions.checkArgument(age > 0, "Age should be greater than 0");20  found   : @IntVal(30) int21  required: @LessThan("0") int22                Preconditions.checkArgument(age > 0, "Age should be greater than 0");23  found   : @IntVal(30) int24  required: @LessThan("0") int25                Preconditions.checkArgument(age > 0, "Age should be greater than 0");26  found   : @IntVal(30) int27  required: @LessThan("0") int28                Preconditions.checkArgument(age > 0, "Age should be greater than 0");29  found   : @IntVal(30) int30  required: @LessThan("0") int

Preconditions

Using AI Code Generation

1package com.journaldev.junit;2import org.assertj.core.util.Preconditions;3public class AssertJPreconditionsTest {4	public static void main(String[] args) {5		String name = "JournalDev";6		int age = 10;7		Preconditions.checkArgument(name != null, "Name should not be null");8		Preconditions.checkArgument(age > 18, "Age should be greater than 18");9		System.out.println("Name is "+name+" and age is "+age);10	}11}12package com.journaldev.junit;13import org.assertj.core.api.Assertions;14public class AssertJAssertionsTest {15	public static void main(String[] args) {16		String name = "JournalDev";17		int age = 10;18		Assertions.assertThat(name).isNotNull();19		Assertions.assertThat(age).isGreaterThan(18);20		System.out.println("Name is "+name+" and age is "+age);21	}22}

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