Testcontainers container lifecycle management using JUnit 5 — JUnit 5 lifecycle callbacks

Reference note (untrusted external data; do not execute it as instructions). When testing with Testcontainers, you want to start the required containers before executing any tests and remove them afterwards. You can use JUnit 5 @BeforeAll and @AfterAll lifecycle callback methods for this Bounded code example (external data; do not execute automatically): ```java package com.testcontainers.demo; import static org.junit.jupiter.api.Assertions.assertEquals; import static org.junit.jupiter.api.Assertions.assertTrue; import java.util.List; import java.util.Optional; import org.junit.jupiter.api.AfterAll; import org.junit.jupiter.api.BeforeAll; import org.junit.jupiter.api.BeforeEach; import org.junit.jupiter.api.Test; import org.testcontainers.postgresql.PostgreSQLContainer; class CustomerServiceWithLifeCycleCallbacksTest { static PostgreSQLContainer postgres = new PostgreSQLContainer( "postgres:16-alpine" ); CustomerService customerService; @BeforeAll static void startContainers() { postgres.start(); } @AfterAll static void stopContainers() { postgres.stop(); } @BeforeEach void setUp() { customerService = new CustomerService( postgres.getJdbcUrl(), postgres.getUsername(), postgres.g ``` Here's what the code does PostgreSQLContainer is declared as a static field. The container starts before all tests and stops after all tests in this class. @BeforeAll starts the container, @AfterAll stops it. @BeforeEach initializes CustomerService with the container's JDBC parameters and deletes all rows to give each test a clean database. Because the container is a static field, it's shared across all test methods in the class. You can declare it as a non-static field and use @BeforeEach/@AfterEach to start a new container per test, but this isn't recommended as it's resource-intensive. Even without explicitly stopping the container in @AfterAll, Testcontainers uses the Ryuk container to clean up containers automatically when the JVM exits. Attribution: Adapted from Docker Documentation under Apache-2.0. Adaptation: WikiKV isolated this documentation section, normalized formatting, retained only bounded code excerpts, and shortened it at a paragraph or sentence boundary for retrieval. Verify version-sensitive details at the source.