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How to print exceptions on console? I am using TestNG and Maven

I want to see the exceptions on console. I am using TestNG with Maven as a build tool. I have defined my testng.xml in the Maven surefire plugin.

https://www.javadoc.io/doc/org.testng/testng/latest/org/testng/reporters/VerboseReporter.html
you should use above reporter , but the constructor expects a string so you cannot initialize it using testng.xml ( if any one knows how to pass string argument to listener in testng.xml please do add it here )
So the work around is to add the listener through script and initiate testng through a java entry file.
public static void main(String[] args) {
TestNG testng = new TestNG();
// Create a list of String
List<String> suitefiles = new ArrayList<String>();
// Add xml file which you have to execute
suitefiles.add(prop.getProperty("path_to_your_existing_testngxml\testng.xml"));
// now set xml file for execution
testng.setTestSuites(suitefiles);
testng.addListener(new VerboseReporter("[TestNG] "));
// finally execute the runner using run method
testng.run();
}
Output:
Note
As this reporter constructor expects a string you should not provide it in your testng.xml you will get initialization error

If you use any kind of logging framework you should probably stick with that.
Otherwise you can always print Exceptions using https://docs.oracle.com/en/java/javase/11/docs/api/java.base/java/lang/Throwable.html#printStackTrace() (and siblings) such as
...
} catch (Exception e) {
e.printStackTrace(System.out);
e.printStackTrace(System.err);
}
...

Allow Evosuite to write files during test generation

Im currently trying to get Evosuite to work with JNA. Consider the following basic example:
import com.sun.jna.ptr.IntByReference;
public class Example {
public static int foo(int x) {
IntByReference c = new IntByReference(x);
if (c.getValue() == 100) {
return 100;
} else {
return 0;
}
}
}
Im running Evosuite from the command line with these options:
java32 -jar evosuite.jar -projectCP "src;E:\evosuite\test\lib\jna-5.2.0.jar" -class Example -criterion branch
Evosuite wont reach 100% branch coverage (only the trivial 33%), but notifies me with this message after the timeout:
* Permissions denied during test execution:
- java.io.FilePermission:
write C:\Users\PC\AppData\Local\Temp\jna--2025216854: 1
I found out that JNA needs to write some temp files in order to work, but Evosuite will block any atempt of file writing during test generation. I understand that this is a reasonable policy in most cases because you dont want Evosuite to write random files to your disk while generating tests for a saveFile() function, but in my case this shouldn't be a problem.
Is there a way to tell Evosuite to allow file writing during test generation or a different approach to generate tests for java programms using the JNA library?

I figured out how to run JNA without the need of writing temporary files thanks to cubrr.
copy the system specific jnidispatch.[dll, ...] file to a folder
add -Djna.boot.library.path=folder -Djna.nounpack=true to the command
Note: the jna.boot.library.path should only point to the containig folder, do not write folder/jnidispatch.
Solution to the initial question:
Setting the evosuite option -Dsandbox=false will remove most restrictions for test generation and finally allowed me to generate my tests!

Using JunitCore for tests in different projects

Background:
I am currently working on a project in eclipse that programatically executes JUnit tests that are pushed to a server.
So far everything works but I would like to know the results of the tests (specifically any failures) so I can push them out to an email. Right now the tests just output to the console but that doesn't seem to give me much output to actually use.
Right now I use the Runtime class to call the tests but that doesn't seem to have the functionality I need for getting results.
I have looked into the JUnitCore class but can't call any tests outside of the current java project.
So my main question would be how can I use JUnitCore to run junit tests in a specific JAR file? Or is there an easier way to approach this problem using a different class?
This is the only thing I've been able to get to work:
RunTests()
{
junitCore = new JUnitCore();
junitCore.run(AllTests.class);
}
But I would like to do something along the lines of this:
RunTests()
{
junitCore = new JUnitCore();
junitCore.run("C:\\$batch\\test\\hil research\\201507071307\\CommsTestRunner\\plugins\\TestSuite\\US35644.class");
}
I would appreciate any suggestions to this problem I am having. I'm an EE and was just introduced to java last month so this has been quite the challenge for me.

JUnitCore expects to read loaded classes, not class files in a JAR. Your real question is likely how to load the JAR (or directory of .class files) so it can be run.
Poke around with URLClassLoader; once you've amended the classpath appropriately, you can get a Class out of findClass and pass it into the JUnitCore methods you've found.

Since the tests might have classes that are also used by your server (but not necessarily at the same version) I would suggest not having your server directly run the tests. Instead, you can have your server start a new JVM that runs the tests. This is how IDEs like Eclipse run tests. You simply need to write a main class that has JUnit run the tests, and serializes the results on disk.
Your main class would look something like this:
public class MyRunner {
public static void main(String... args) throws IOException {
String path = System.getProperty("resultPath");
if (path == null) {
throw new NullPointerException("must specify resultPath property");
}
// Possibly install a security manager to prevent calls to System.exit()
Result result = new JUnitCore().runMain(new RealSystem(), args);
try (ObjectOutputStream out = new ObjectOutputStream(new FileOutputStream(path)) {
out.writeObject(result);
}
System.exit(result.wasSuccessful() ? 0 : 1);
}
}
Then your server simply needs to construct a java command line with the jars that include the tests, the JUnit jar file, and a jar that contains MyRunner.

Building Java file at runtime & running JUnit test on that class file

I am trying to build a Dynamic web project where user can practice Java code.
I got success on writing the code written by user in a .java file, compile the code & get error messages using Java Compile API.
Now, I need to run JUnit 1.4 Compatible test on that code.
I researched for it, and found something like parameterized junit testing. But my view on how should it be done isn't still clear.
UPDATE
This (http://codingbat.com/prob/p171896) is the exact thing what I'm trying to implement.

I solved this problem with the following steps:
Compile the JUnit TestClass and the ClassToTest
JavaCompiler compiler = ToolProvider.getSystemJavaCompiler();
int compilerResult = compiler.run(null, null, null,"/path/to/TestClass.java", "/path/to/ClassToTest.java");
System.out.println("Compiler result code: " + compilerResult);
Load the compiled classes into the classloader
File dir = new File("/path/to/class/files/");
URL url = dir.toURI().toURL();
URL[] urls = {url};
ClassLoader classLoader = new URLClassLoader(urls);
Run the tests (make sure that you add junit as a dependency of your project)
Class<?> junitTest = Class.forName("TestClass", true, classLoader);
Result result = junit.run(junitTest);
Edit: If you're not needing the JUnit tests to be dynamic you can skip the compilation of those tests and add them here: junit.run(JunitTest.class)

Empty benchmarks when running JMH samples in Intellij IDEA

I have some problem with using JMH.
So, I create an empty project in Intellij Idea, then in project structure add jmh-core jar file. Finally, try to run samples, for example
import org.openjdk.jmh.annotations.GenerateMicroBenchmark;
import org.openjdk.jmh.runner.Runner;
import org.openjdk.jmh.runner.RunnerException;
import org.openjdk.jmh.runner.options.Options;
import org.openjdk.jmh.runner.options.OptionsBuilder;
public class JMHSample_01_HelloWorld {
#GenerateMicroBenchmark
public void wellHelloThere() {
// this method was intentionally left blank.
}
public static void main(String[] args) throws RunnerException {
Options opt = new OptionsBuilder()
.include(".*" + JMHSample_01_HelloWorld.class.getSimpleName() + ".*")
.forks(1)
.build();
new Runner(opt).run();
}
}
but result is
No matching benchmarks. Miss-spelled regexp?
Use EXTRA verbose mode to debug the pattern matching.
Process finished with exit code 0
with using verbosity(VerboseMode.EXTRA)
No matching benchmarks. Miss-spelled regexp?
Benchmarks:
Process finished with exit code 0
I tried to change output path to projectFolder\target\classes but nothing was changed.
Then I looked at the source code in the debug mode and see that resource = "/META-INF/MicroBenchmarks",urls.hasMoreElements() is false and therefore benchmarks is empty. Then I saw at the samples jar file which has MicroBenchmarks file with information about tests and work well.
So, the question is what do I do wrong?
Do I have to write information about test manually?

Please follow the instructions on JMH page to set up the benchmark project, namely:
"Make sure you tried these things before getting support:
- Archetypes provide the golden build configuration. Try to generate the clean JMH benchmark project and transplant the benchmark
there. This is important to try when upgrading to the newer JMH
versions, since the minute differences in the build configurations may
attribute to the failures you are seeing."
If you'd follow that, you will notice that you also need to add jmh-generator-annprocess as the dependency, and make sure it runs before you run any test.