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Subcomponents require public constructors on pure-static modules

See original GitHub issue


class MyModule {
    static String provideStaticDependency() {
        return "a static dependency";

    private MyModule() {
        throw new UnsupportedOperationException("No instances!");

@Subcomponent(modules = MyModule.class)
interface MySubComponent {
    String staticDependency();

interface MyComponent {
    MySubComponent subComponent();

Dagger complains:

error: MySubComponent requires modules which have no visible default constructors. Add the following modules as parameters to this method: MyModule
    MySubComponent subComponent();

If I make the module constructor public, it solves the warning, but the generated code never calls that constructor (as is evidenced by the fact that my application never crashes).

Issue Analytics

  • State:closed
  • Created 7 years ago
  • Reactions:2
  • Comments:16

github_iconTop GitHub Comments

gabrielittnercommented, May 6, 2016

Also happens for abstract modules of subcomponents which only have @Binds methods.

gk5885commented, Dec 26, 2016

Hey, thanks for the bump. I was actually working on this just the other day because it was annoying me too and we should have fix for the next release.

Read more comments on GitHub >

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