ClassTemplate.java

/*
 * Copyright 2015-2025 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.EXPERIMENTAL;

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

import org.apiguardian.api.API;
import org.junit.jupiter.api.extension.AfterClassTemplateInvocationCallback;
import org.junit.jupiter.api.extension.BeforeClassTemplateInvocationCallback;
import org.junit.jupiter.api.extension.ClassTemplateInvocationContext;
import org.junit.jupiter.api.extension.ClassTemplateInvocationContextProvider;
import org.junit.platform.commons.annotation.Testable;

/**
 * {@code @ClassTemplate} is used to signal that the annotated class is a
 * <em>class template</em>.
 *
 * <p>In contrast to regular test classes, a class template is not directly
 * a test class but rather a template for a set of test cases. As such, it is
 * designed to be invoked multiple times depending on the number of {@linkplain
 * ClassTemplateInvocationContext invocation
 * contexts} returned by the registered {@linkplain
 * ClassTemplateInvocationContextProvider
 * providers}. Must be used together with at least one provider. Otherwise,
 * execution will fail.
 *
 * <p>Each invocation of a class template method behaves like the execution
 * of a regular test class with full support for the same lifecycle callbacks
 * and extensions.
 *
 * <p>{@code @ClassTemplate} may be combined with {@link Nested @Nested} and
 * a class template may contain regular nested test classes or nested
 * class templates.
 *
 * <p>{@code @ClassTemplate} may also be used as a meta-annotation in order
 * to create a custom <em>composed annotation</em> that inherits the semantics
 * of {@code @ClassTemplate}.
 *
 * <h2>Inheritance</h2>
 *
 * <p>This annotation is inherited to subclasses.
 *
 * @since 5.13
 * @see TestTemplate
 * @see ClassTemplateInvocationContext
 * @see ClassTemplateInvocationContextProvider
 * @see BeforeClassTemplateInvocationCallback
 * @see AfterClassTemplateInvocationCallback
 */
@API(status = EXPERIMENTAL, since = "6.0")
@Documented
@Inherited
@Retention(RetentionPolicy.RUNTIME)
@Target({ ElementType.ANNOTATION_TYPE, ElementType.TYPE })
@Testable
public @interface ClassTemplate {
}