如何在 junit 集成测试期间启动/停止 java 应用程序

Question

I have done a fair amount of research and don't see a good way to do this. I have a java application that has integration tests. For the sake of the integration tests, the tests need to start the actual application. This is done like so in each junit test.

@BeforeClass
final public static void setup() {
    Application.main(new String[]{});
}

How do I shut down the application though? I notice it stays around as rogue process after the junit tests shutdown. In addition I have done this with springboot before and am aware that springboot provides annotations. We cannot use springboot though for this. So i need to find a non spring way. How do I shut down the application in a junit test?

Answer 1

I cannot reproduce this with Gradle 6.3 and JUnit 5; I briefly see a [java] <defunct> process in the ps output, and that disappears on its own. Maybe it's because I only run a single test suite and when you run more you'd need to cleanup after each.

That said, look into the Java process API . Start the app as in this question , but hold on to the Process returned from ProcessBuilder.start() and call its destroy() method in your @AfterClass method.

package com.example.demo;

import java.util.ArrayList;
import org.junit.jupiter.api.*;

public class DemoApplicationTests {
    private static Process process;

    @BeforeAll
    public static void beforeClass() throws Exception {
        ArrayList<String> command = new ArrayList<String>();
        command.add(System.getProperty("java.home") + "/bin/java"); // quick and dirty for unix
        command.add("-cp");
        command.add(System.getProperty("java.class.path"));
        command.add(DemoApplication.class.getName());

        ProcessBuilder builder = new ProcessBuilder(command);
        process = builder.inheritIO().start();
    }

    @Test
    void whatever() {
        // ...
    }

    @AfterAll
    public static void afterClass() {
        process.destroy();  
    }
}