How to tell IDEA/Studio that the null check has been done?

Question

I\'m developing with Android Studio/IntelliJ IDEA.

I have enabled the inspection check called "Constant conditions & exceptions" that shows a warning if

Answer 1

Unfortunately marked as "right answer" solution is of date. But I found equivalent for me solution.

The new versions of IDE work correctly with static methods. So the example from the question won't throw warning anymore.

TextUtils#isEmpty(String);

public static boolean isEmpty(CharSequence str) {
    // your checks
}

Answer 2

You could use //noinspection ConstantConditions that will remove the NPE warning for the following line, like this:

String encoding = contentEncoding == null ? null : contentEncoding.getValue();

//noinspection ConstantConditions
if (!TextUtils.isEmpty(encoding) && encoding.equalsIgnoreCase("gzip")) {
    inputStream = new GZIPInputStream(entity.getContent());
} else {
    inputStream = entity.getContent();
}

Answer 3

You can use @SuppressWarnings("ConstantConditions") annotation.

@SuppressWarnings("ConstantConditions")
@Override
public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int indexViewType) {
    if (inflater == null) {
        inflater = LayoutInflater.from(parent.getContext());
    }
    ItemViewProvider provider = getProviderByIndex(indexViewType);
    provider.adapter = MultiTypeAdapter.this;
    return provider.onCreateViewHolder(inflater, parent);
}

Answer 4

1. Select "TextUtils.isEmpty".
2. Right Click -> Show Context Actions -> Add Method Contract.
3. Enter "null -> true".
4. Save the configuration xml.

Please check the details here

Answer 5

You can look into the link that Peter Gromov mention in his answer.

Created some simple classes that resemble your setup:

A class with a method annotated with @Nullable:

The TextUtil class with it's isEmpty method:

And finally the main class calling the TextUtil#isEmpty:

Now if you enter the File -> Settings... and go to Inspections ->Constant conditions & exceptions part you can change the Configure Assert/Check Methods to cater for your isEmpty method:

Add a new IsNull check method:

Enter the TextUtil class, isEmpty method and CharSequence parameter:

This gives this Assert/Check Method Configuration window:

Press Ok and then Ok again to go back to the editor view and you'll see that the inspection disappeared:

You are actually telling IntelliJ that the isEmpty method is doing a null check on the str parameter.

Answer 6

See http://www.jetbrains.com/idea/webhelp/configuring-check-assert-methods.html for IDEA 12. In IDEA 13 EAP, you can add method contract: http://youtrack.jetbrains.com/issue/IDEA-93372