How do I programmatically run all the JUnit tests in my Java application?

Question

From Eclipse I can easily run all the JUnit tests in my application.

I would like to be able to run the tests on target systems from the application jar, without Eclipse

Answer 1

I ran into a minor problem with my last solution. If I ran "all tests" from Eclipse they ran twice because they ran the individual tests AND the suite. I could have worked around that, but then I realized there was a simpler solution:

package suneido;

import java.io.IOException;
import java.util.ArrayList;
import java.util.Enumeration;
import java.util.jar.JarEntry;
import java.util.jar.JarFile;

public class RunAllTests {

    public static void run(String jarfile) {
        String[] tests = findTests(jarfile);
        org.junit.runner.JUnitCore.main(tests);
    }

    private static String[] findTests(String jarfile) {
        ArrayList tests = new ArrayList();
        try {
            JarFile jf = new JarFile(jarfile);
            for (Enumeration e = jf.entries(); e.hasMoreElements();) {
                String name = e.nextElement().getName();
                if (name.startsWith("suneido/") && name.endsWith("Test.class")
                        && !name.contains("$"))
                    tests.add(name.replaceAll("/", ".")
                            .substring(0, name.length() - 6));
            }
            jf.close();
        } catch (IOException e) {
            throw new RuntimeException(e);
        }
        return tests.toArray(new String[0]);
    }

    public static void main(String[] args) {
        run("jsuneido.jar");
    }

}