@Override is not allowed when implementing interface method

If your project has multiple modules, also check that every module uses language level 6 or above, or use the project's language level (see Project Settings > Modules > xxx > Language level).

You may need to reload your project once it is modified.


A simpler solution - inline

  1. Put the caret on the @Override word and move the caret on the left side until the red bulb icon will appear. Then click on it.

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  2. Click on Set language level to 6 - Override in interfaces

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The method above is an alternative to the following approach:

  1. Go to File > Project Structure... or press Ctrl+Alt+Shift+S

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  2. Go to Project Settings > Modules > Sources > Language level and choose any level that is 6 or greater than 6.

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At your module/project, Right click to see context menu:

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Choose Open Module Settings or press F4. In setting windows:

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Set value for Choose Language level section.


You also should check Project language level by this way: press Ctrl+Alt+Shift+S

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