This inspection analyzes method control and data flow to report possible conditions that are always true or false,
expressions whose value is statically proven to be constant, and situations that can lead to nullability contract violations.
Variables, method parameters and return values marked as @Nullable
or @NotNull
are treated as nullable (or not-null, respectively)
and used during the analysis to check nullability contracts, e.g. report NullPointerException
(NPE) errors that might be produced.
More complex contracts can be defined using @Contract
annotation, for example:
@Contract("_, null -> null")
— method returns null if its second argument is null
@Contract("_, null -> null; _, !null -> !null")
— method returns null if its second argument is null and not-null otherwise
@Contract("true -> fail")
— a typical assertFalse
method which throws an exception if true
is passed to it
The inspection can be configured to use custom @Nullable
/@NotNull
annotations (by default the ones from annotations.jar will be used)