org.junitpioneer.jupiter.RestoreSystemProperties Maven / Gradle / Ivy
/*
* Copyright 2016-2023 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
*
* http://www.eclipse.org/legal/epl-v20.html
*/
package org.junitpioneer.jupiter;
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.junit.jupiter.api.extension.ExtendWith;
/**
* {@code @RestoreSystemProperties} is a JUnit Jupiter extension to restore the entire set of
* system properties to the original value, or the value of the higher-level container, after the
* annotated element is complete.
*
* Use this annotation when there is a need programmatically modify system properties in a test
* method or in {@code @BeforeAll} / {@code @BeforeEach} blocks.
* To simply set or clear a system property, consider {@link SetSystemProperty @SetSystemProperty} or
* {@link ClearSystemProperty @ClearSystemProperty} instead.
*
* {@code RestoreSystemProperties} can be used on the method and on the class level.
* When placed on a test method, a snapshot of system properties is stored prior to that test.
* The snapshot is created before any {@code @BeforeEach} blocks in scope and before any
* {@link SetSystemProperty @SetSystemProperty} or {@link ClearSystemProperty @ClearSystemProperty}
* annotations on that method. After the test, system properties are restored from the
* snapshot after any {@code @AfterEach} have completed.
*
*
When placed on a test class, a snapshot of system properties is stored prior to any
* {@code @BeforeAll} blocks in scope and before any {@link SetSystemProperty @SetSystemProperty}
* or {@link ClearSystemProperty @ClearSystemProperty} annotations on that class.
* After the test class completes, system properties are restored from the snapshot after any
* {@code @AfterAll} blocks have completed.
* In addition, a class level annotation is inherited by each test method just as if each one was
* annotated with {@code RestoreSystemProperties}.
*
*
During
* parallel test execution,
* all tests annotated with {@link RestoreSystemProperties}, {@link SetSystemProperty},
* {@link ReadsSystemProperty}, and {@link WritesSystemProperty}
* are scheduled in a way that guarantees correctness under mutation of shared global state.
*
* For more details and examples, see
* the documentation on
* @ClearSystemProperty, @SetSystemProperty, and @RestoreSystemProperties.
*
* Note: System properties are normally just a hashmap of strings, however, it is
* technically possible to store non-string values and create nested {@code Properties} with inherited /
* default values. Within the context of an element annotated with {@link RestoreSystemProperties},
* non-String values are not preserved and the structure of nested defaults are flattened.
* After the annotated context is exited, the original Properties object is restored with
* all its potential (non-standard) richness.
*
* @since 2.0.0
*/
@Retention(RetentionPolicy.RUNTIME)
@Target({ ElementType.METHOD, ElementType.TYPE })
@Inherited
@WritesSystemProperty
@ExtendWith(SystemPropertyExtension.class)
public @interface RestoreSystemProperties {
}