Mock Lambda Context and Logger while testing AWS Lambda RequestHandler (with JUnit4)

LambdaRequestHandlerWithLoggerTest.java

//In the test class
import com.amazonaws.services.lambda.runtime.Context;
import com.amazonaws.services.lambda.runtime.LambdaLogger;
import org.junit.runner.RunWith;
import org.mockito.junit.MockitoJUnitRunner;
import org.mockito.Mock;
import org.junit.Before;
import org.junit.Test;
import static org.mockito.Mockito.when;
import static org.mockito.Mockito.doAnswer;
import static org.mockito.ArgumentMatchers.anyString;

@RunWith(MockitoJUnitRunner.class)//without this runner - mocks would be "null"
public class LambdaRequestHandlerTest {
    private LambdaRequestHandler handler;
    @Mock
    Context context;
    @Mock
    LambdaLogger loggerMock;

    @Before
    public void setUp() throws Exception {
      when(context.getLogger()).thenReturn(loggerMock);
        
      doAnswer(call -> {
            System.out.println((String)call.getArgument(0));//print to the console
            return null;
        }).when(loggerMock).log(anyString());
        
      handler = new LambdaRequestHandler();
    }

    @Test
    public void handleRequest() {
        String respond = handler.handleRequest("some input", context);
    }
}

//In the request handler
public class LambdaRequestHandler implements RequestHandler<String, String> {
    @Override
    public String handleRequest(String input, Context context) {
      LambdaLogger logger = context.getLogger();
      logger.log("some log message");
      
      return "some output";
    }
}