payara.java

// Here's the network where both containers will join
static final Network NET = Network.newNetwork();

// The database container will join the network under the 'mysql' alias
@Container
static MySQLContainer dbContainer = 
  new MySQLContainer<>(DockerImageName.parse("mysql:8.0"))
      .withNetwork(NET)
      .withNetworkAliases("mysql");

// The Payara Micro container will also join the network and be configured to depend on the database container
@Container
static GenericContainer microContainer = 
  new GenericContainer(DockerImageName.parse("payara/micro-jdk11"))
      .withExposedPorts(8080)
      .dependsOn(dbContainer)
      .withNetwork(NET)
      .withCopyFileToContainer(warFile, "/opt/payara/deployments/app.war")
      .waitingFor(Wait.forLogMessage(".* Payara Micro .* ready in .*\\s", 1))
      .withEnv("DB_JDBC_URL", String.format("jdbc:mysql://mysql:3306/%s", dbContainer.getDatabaseName()))
      .withEnv("DB_USER", dbContainer.getUsername())
      .withEnv("DB_PASSWORD",  dbContainer.getPassword())
                                              .withCommand("--deploy /opt/payara/deployments/app.war --contextRoot /");