org.junit.jupiter.api.BeforeAll Maven / Gradle / Ivy

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 * Copyright 2015-2020 the original author or authors.
 *
 * All rights reserved. This program and the accompanying materials are
 * made available under the terms of the Eclipse Public License v2.0 which
 * accompanies this distribution and is available at
 *
 * https://www.eclipse.org/legal/epl-v20.html
 */

package org.junit.jupiter.api;

import static org.apiguardian.api.API.Status.STABLE;

import java.lang.annotation.Documented;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;

import org.apiguardian.api.API;

/**
 * {@code @BeforeAll} is used to signal that the annotated method should be
 * executed before all tests in the current test class.
 *
 * In contrast to {@link BeforeEach @BeforeEach} methods, {@code @BeforeAll}
 * methods are only executed once for a given test class.
 *
 * 
Method Signatures
 *
 * {@code @BeforeAll} methods must have a {@code void} return type,
 * must not be {@code private}, and must be {@code static} by default.
 * Consequently, {@code @BeforeAll} methods are not
 * supported in {@link Nested @Nested} test classes or as interface default
 * methods unless the test class is annotated with
 * {@link TestInstance @TestInstance(Lifecycle.PER_CLASS)}. {@code @BeforeAll}
 * methods may optionally declare parameters to be resolved by
 * {@link org.junit.jupiter.api.extension.ParameterResolver ParameterResolvers}.
 *
 * 
Inheritance and Execution Order
 *
 * {@code @BeforeAll} methods are inherited from superclasses as long as
 * they are not hidden or overridden. Furthermore,
 * {@code @BeforeAll} methods from superclasses will be executed before
 * {@code @BeforeAll} methods in subclasses.
 *
 * 
Similarly, {@code @BeforeAll} methods declared in an interface are
 * inherited as long as they are not hidden or overridden,
 * and {@code @BeforeAll} methods from an interface will be executed before
 * {@code @BeforeAll} methods in the class that implements the interface.
 *
 * 
JUnit Jupiter does not guarantee the execution order of multiple
 * {@code @BeforeAll} methods that are declared within a single test class or
 * test interface. While it may at times appear that these methods are invoked
 * in alphabetical order, they are in fact sorted using an algorithm that is
 * deterministic but intentionally non-obvious.
 *
 * 
In addition, {@code @BeforeAll} methods are in no way linked to
 * {@code @AfterAll} methods. Consequently, there are no guarantees with regard
 * to their wrapping behavior. For example, given two
 * {@code @BeforeAll} methods {@code createA()} and {@code createB()} as well as
 * two {@code @AfterAll} methods {@code destroyA()} and {@code destroyB()}, the
 * order in which the {@code @BeforeAll} methods are executed (e.g.
 * {@code createA()} before {@code createB()}) does not imply any order for the
 * seemingly corresponding {@code @AfterAll} methods. In other words,
 * {@code destroyA()} might be called before or after
 * {@code destroyB()}. The JUnit Team therefore recommends that developers
 * declare at most one {@code @BeforeAll} method and at most one
 * {@code @AfterAll} method per test class or test interface unless there are no
 * dependencies between the {@code @BeforeAll} methods or between the
 * {@code @AfterAll} methods.
 *
 * 
Composition
 *
 * {@code @BeforeAll} may be used as a meta-annotation in order to create
 * a custom composed annotation that inherits the semantics of
 * {@code @BeforeAll}.
 *
 * @since 5.0
 * @see AfterAll
 * @see BeforeEach
 * @see AfterEach
 * @see Test
 * @see TestFactory
 * @see TestInstance
 */
@Target({ ElementType.ANNOTATION_TYPE, ElementType.METHOD })
@Retention(RetentionPolicy.RUNTIME)
@Documented
@API(status = STABLE, since = "5.0")
public @interface BeforeAll {
}