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I have a class that I mocked using Mockito. The original class is quite simple such as the following.

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
public class MyNewClass{
    private static Logger logger = LoggerFactory.getLogger(MyNewClass.class);
     * Only for unit/integration test, otherwise no need to use this method.
    protected static void setLogger(Logger logger) {
        MyNewClass.logger = logger;
The method logger.info("SomeString") will print to a file since it is configured for production.
In my test class how do I print to a console instead? I'm currently in Eclipse.
public class MyNewClassTest{
    private static Logger mockedLogger = Mockito.mock(Logger.class);
    @Before
    public void setUp() throws Exception {
        MyNewClass.setLogger(mockedLogger);
        // TODO how to print to console instead of file.
Then how do I overwrite the mockedLogger.info("SomeString") to print to console , simply by using System.out.println()
                Inject the logger, don't construct it statically. Tools like PowerMock should only be  used as a last resort since they utilize byte code manipulation. Also, you can reconfigure the logger for tests.
– Turing85
                Aug 24, 2020 at 18:51
Honestly, your approach seems to me a bit odd: I'd rather define separate logging configuration for tests. Anyways, If you have good reasons for what you are trying to achieve, here is how you can do it:
@Before
public void setUp() {
    MyNewClass.setLogger(mockedLogger);
    Mockito.doAnswer(invocation -> {
        System.out.println((String) invocation.getArgument(0));
        return null;
    }).when(mockedLogger).info(anyString());
Using PowerMock, you could get rid of the logger setter in the MyNewClass by mocking LoggerFactory:
@RunWith(PowerMockRunner.class)
@PrepareForTest(LoggerFactory.class)
public class MyNewClassTest {
    private static Logger mockedLogger = Mockito.mock(Logger.class);
    @Before
    public void setUp() {
        PowerMockito.mockStatic(LoggerFactory.class);
        PowerMockito.when(LoggerFactory.getLogger(any(Class.class))).thenReturn(mockedLogger);
        Mockito.doAnswer(invocation -> {
            System.out.println((String) invocation.getArgument(0));
            return null;
        }).when(mockedLogger).info(anyString());
        
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