Why does Java throw NullPointerException using HashMap with Dagger?

Asked Jul 23 '20 at 07:23

Active Jul 23 '20 at 08:25

Viewed 40 times

First I create Dagger Component and Module.

@Singleton
@Component(modules = {UploadModule.class})
public interface UploadComponent {
    void inject(UploadS3ToMap requestHandler);
}

Module:

private Map<String, String> uploadMap = new HashMap<String, String>();

@Singleton
@Provides
Map<String, String> getUploadMap() {
    return uploadMap;
}

And than trying to use it in my Class:

@Inject
Map<String,String> getUploadMap;

getUploadMap.put("test", "testIssue");
return getUploadMap.toString();

And I have an Exception: nulljava.lang.NullPointerException

What is wrong with it?

edited Jul 23 '20 at 08:25

asked Jul 23 '20 at 07:23

mvn.2047

Someone has marked a question to be closed. If this issue is clear for you, what prevent you to write a short answer for author and community? – mvn.2047 Jul 23 '20 at 07:36
Exceptions are thrown, not returned. – user207421 Jul 23 '20 at 08:21
Obviously your map is not being injected. You should provide a [mre] demonstrating the problem is you need more help. – Slaw Jul 23 '20 at 09:12
@Slaw Thank your for your support. I am working on it now. – mvn.2047 Jul 23 '20 at 09:22

Why does Java throw NullPointerException using HashMap with Dagger?

0 Answers0