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VS Code still runs Java file even when build fails?

Simple question here. Here is my Java file:
public class Test {
public static void main(String []args) {
System.out.println("It ran!");
}
void a() {
qweifjew;
}
}
When I press "Run" on VS Code, it says build failed do you want to continue? Makes sense since I have compile-time errors. But when I press continue, it is still able to run and display "It ran!". How come?
For more information on the run command:
C:\Users\jeffe\coding-tutorials\learning-jest> cd c:\Users\jeffe\coding-tutorials\learning-jest && c:\Users\jeffe\.vscode\extensions\vscjava.vscode-java-debug-0.27.1\scripts\launcher.bat "C:\Program Files\Java\jdk-11.0.2\bin\java.exe" -Dfile.encoding=UTF-8 -cp C:\Users\jeffe\AppData\Roaming\Code\User\workspaceStorage\5e0a770d0910238b624ead6f98bca1ec\redhat.java\jdt_ws\learning-jest_f8aabfb2\bin Test
It ran!

This is the decompiled .class file of your code:
public class Test {
public Test() {
}
public static void main(String[] args) {
System.out.println("It ran!ddfseffe");
}
void a() {
throw new Error("Unresolved compilation problems: \n\tSyntax error, insert \"VariableDeclarators\" to complete LocalVariableDeclaration\n\tqweifjew cannot be resolved\n");
}
}

You have Auto Save ON in VS code ?
It's able to run a previous successful build to give you an output.

How to embed every test in a wrapper logic?

Given the requirement that every junit test have to run in the following wrapper:
#Test
public void testFooBar() {
SpecialLogic.runWith(new SpecialLogic("blah", "foo", ANYTHING), () -> {
// my test
});
}
I am trying to avoid adding SpecialLogic.runWith(...) for each test.
Is there any possibility by using #BeforeEach or any other way?
Otherwise, there is much of duplicated code:
#Test
public void testFooBar_2() {
SpecialLogic.runWith(new SpecialLogic("blah", "foo", ANYTHING), () -> {
// my test logic 2
});
}
#Test
public void testFooBar_3() {
SpecialLogic.runWith(new SpecialLogic("blah", "foo", ANYTHING), () -> {
// my test logic 3
});
}

There are two ways of doing this:
Write your custom Runner, all the tests will have to run with this runner.
This may be inappropriate if you already use another runner (say for spring or mockito)
Write your own Rule. The rule is a little bit newer way of doing what you've asked for,
and it doesn't "occupy" the slot of a runner which can be only one.
public final class SampleRule implements TestRule {
#Override public Statement apply(final Statement base,
final Description description) {
return new Statement() {
#Override public void evaluate() throws Throwable {
// do your stuff before actually running the test
try {
base.evaluate(); // This line actually runs the test.
} finally {
// do your stuff after running a test
}
}
};}}
Here is one of numerous guides for writing Rules:

Looks like you should implement your own TestRunner to wrap your custom logic around each test method call. There is an article over at Baelung explaining how this works.

#Before and #After? It won't use closures but should be functionally the same.
https://junit.org/junit4/javadoc/latest/org/junit/Before.html
https://junit.org/junit4/javadoc/latest/org/junit/After.html

junit detect if a test is the only one run

I have a test like this:
#Test public void testInfinite() {
while (true) {runSomeOtherTest();waitForSomeSignal();}
We have a spring context which takes a while to initialize - and with the above test and hotswapping - it means I can debug changes in seconds rather than waiting for a restart.
However, obviously checking this into the CI system is a bit of a problem, and of course something I've accidentally done several times. I'm wondering if it's possible (without changing the testrunner, because we are already using a custom one, that's hard to modify) to determine if it's the only test running. eg I want to be able to say
#Test public void testInfinite() {
if (!testIsTheOnlyTestWhichWillBeRun()) return; ...
So, bottom line - what I'm looking for is that if I right click on exactly that test and say run, in the IDE - it will do that - in all other cases - eg I right click and run the whole class - or I do it from gradle, or from CI - the test does nothing and just returns immediately.

You can evaluate a System property:
#Test public void testInfinite() {
if (!"true".equals(System.getProperty("junit.runloop"))) {
return;
}
}
In your IDE/local run, you can then run the test with -Djunit.runloop=true.
To not polute the test cases themselves, you could write a JUnit rule that does this:
public class TestInfinite implements TestRule {
#Override
public Statement apply(Statement base, Description description) {
return new Statement() {
public void evaluate() throws Throwable {
do {
base.evaluate();
} while ("true".equals(System.getProperty("junit.runloop")));
}
};
}
}
So in your test, you can attach them:
public class YourTest {
#Rule public TestInfinite = new TestInfinite();
#Test public void testInfinite() {
// this will be run once if property is not set,
// in an endless loop if it is
}
}

Gradle run test classes in parallel with methods of same class running in same thread

I'm having a few Junit test classes. I want to run them in 2 threads, so included maxParallelForks = 2 . I want to make sure that tests of same class run in same thread sequentially. How to achieve this? (I use SpringRunner.)

I was using #RunWith(Suite.class) to run multiple test classes. So I created a new Runner class and this solved my problem.
public class ParallelExecutor extends Suite {
public ParallelExecutor(Class<?> klass, RunnerBuilder builder) throws InitializationError, IOException, InterruptedException {
super(klass, builder);
setScheduler(new RunnerScheduler() {
private final ExecutorService service = Executors.newFixedThreadPool(10);
public void schedule(Runnable childStatement) {
service.submit(childStatement);
}
public void finished() {
try {
service.shutdown();
service.awaitTermination(Long.MAX_VALUE, TimeUnit.NANOSECONDS);
} catch (InterruptedException e) {
e.printStackTrace(System.err);
}
}
});
}
}

As far as I can see from a quick look at the Gradle sources, this should exactly be the option you want. maxParallelForks make test classes be executed in parallel, not single test methods.

How to run tearDown type method for a specific test in JUnit class with multiple tests?

I have a junit testCase class with multiple test methods in it ( As requirement , we don't want to create separate class for each test.)
I wanna create a tearDown type method for EACH test method , which will run specifically for that test. Not for ALL test.
My problem is , in many tests i Insert record in database, test it and delete it after test.
But, If a test fails mid way , control don't reaches till end my dummy record ain't deleting.
I think only ONE tearDown() is allowed for one class, and this tearDown() don't know what object/record i created or inserted and what to delete!!!
I want to create a tearDown() or #After method just for one specific test. Something like finally{} in java for each method.
For Eg:
public class TestDummy extends TestCase {
public void testSample1(){
InsertSomeData1();
assertFalse(true);
runTearDown1();
}
public void testSample2(){
InsertSomeData2();
assertFalse(true);
runTearDown2();
}
public void runTearDown1(){
deleteDummyDatafromTestSample1....
}
public void runTearDown2(){
deleteDummyDatafromTestSample2....
}
}
Here control will never go to runTearDown1() or runTearDown2() and I don't a one common tearDown() because it won't know what data I inserted and thats specific to each method.

It seems your test relies on a fixed database, and future tests will break if your current test breaks. What I'd recommend is not to focus on this particular problem (a test-specific tearDown method that runs for each test), but your main problem - borken tests. Before your test run, it should always work with a clean database, and this should be the case for each test. Right now, your first test has a relationship with the second (through the database).
What the right approach would be is that you recreate your database before each test, or at the very least reset it to a basic state. In this case, you'll want a test like this:
public class TestDummy {
// this code runs (once) when this test class is run.
#BeforeClass
public void setupDatabase() {
// code that creates the database schema
}
// this code runs after all tests in this class are run.
#AfterClass
public void teardownDatabase() {
// code that deletes your database, leaving no trace whatsoever.
}
// This code runs before each test case. Use it to, for example, purge the
// database and fill it with default data.
#Before
public void before() {
}
// You can use this method to delete all test data inserted by a test method too.
#After
public void after() {
}
// now for the tests themselves, we should be able to assume the database will
// always be in the correct state, independent from the previous or next test cases.
#Test
public void TestSample2() {
insertSomeData();
assertTrue(someData, isValid());
}
}
Disclaimer: JUnit 4 tests (using annotations), might not be the right annotations, might not even be the right answer(s).

You could have smth like this:
interface DBTest {
void setUpDB();
void test();
void tearDownDB();
}
class DBTestRunner {
void runTest(DBTest test) throws Exception {
test.setUpDB();
try {
test.test();
} finally {
test.tearDownDB();
}
}
}
public void test48() throws Exception {
new DBTestRunner().runTest(new DBTest() {
public void setUpDB() {...}
public void test() {...}
public void tearDownDB() {...}
});
}

#iluxa . Gr8.. Your solution is perfect!!! In one test class i created two tests test48 and test49 (same as required in my code above testSample1 and testSample2) and viola! every test method now gets its own setup() and tearDown. Only this solution looks little complicated as need to use DBTestRunner in each method, but I don't see any better solution. I was thinking Junit may have some direct solution. like #After or tearDown() with some parameter or something.
Tks a lot.

Use MethodRule:
public class MyRule implements MethodRule {
#Override
public Statement apply(final Statement base, FrameworkMethod method, Object target) {
return new Statement() {
#Override
public void evaluate() throws Throwable {
try {
base.evaluate();
} catch (AssertionError e) {
doFail();
} finally {
doAnyway();
}
}
};
}
}
Then declare it in your test class:
public class TestDummy{
public MethodRule rule = new MyRule();
......
}