reason: no instance(s) of type variable(s) T exist so that void conforms to using mockito

I want to throw an Exception when running a void method

when(booking.validate(any())).thenThrow(BookingException.builder().build());

but I have a compilation error:

Required type: T
Provided: void
reason: no instance(s) of type variable(s) T exist so that void conforms to T

/**
* Use <code>doThrow()</code> when you want to stub the void method with an exception.
* <p>
* Stubbing voids requires different approach from {@link Mockito#when(Object)} because the compiler
* does not like void methods inside brackets...
* <p>
* Example:
*
* <pre class="code"><code class="java">
* doThrow(new RuntimeException()).when(mock).someVoidMethod();
* </code></pre>
*
* @param toBeThrown to be thrown when the stubbed method is called
* @return stubber - to select a method for stubbing
*/
@CheckReturnValue
public static Stubber doThrow(Throwable... toBeThrown) {
return MOCKITO_CORE.stubber().doThrow(toBeThrown);
}

I Figured out the right syntax.
```
Service mockedService = new DefaultServie();
doNothing().when(mockedService).sendReportingLogs(null);
```
Hope this answers the questions

Just complementing @Shane 's comment, which was a life saver but not very clear.

Example on how to throw PersistenceException from a repository method:

doThrow(new PersistenceException())
.when(outboxRepository)
.delete(isA(WorkersEphemeralOutboxEntry.class));

I find this especially helpful when you have overloaded methods and the compiler cannot figure out which one to call with any() and any(Class.class) gives you compiling error.

For **void** methods, I think you need to use the `doThrow` syntax.

So in your case it would be:

```java
doThrow(BookingException.builder().build())
.when(booking)
.validate(any());
```