Recognize contractual non-nullness of standard library functions

The nullness analyzer does not recognize that certain standard library functions will, contractually, never return null. A common example would be Integer::toString.

These methods will generate unchecked cast warnings if assigned to a @Nonnull field.

As I understand, the plugin relies on Eclipse JDT for nullness analysis. I have come across LastNPE, which publishes JDT-compatible external null annotation files for many common libraries.

Would it be possible to include these annotations by default? Alternatively, if this is not desirable, could EAA files be supported by the plugin?

Environment

• Operating System: Windows 10 Enterprise
• JDK version: openjdk 11.0.12 2021-07-20
• Visual Studio Code version: 1.71.2
• Java extension version: v1.11.0

issue ではソースファイルもテストも指定されていません。まず、拡張機能が nullness 解析を Eclipse JDT にどのように委譲しているかを調べ、LastNPE の JDT 互換アノテーションと要求されている EAA サポートを比較してください。標準ライブラリの Integer::toString のようなメソッドを @Nonnull フィールドに代入したときに、unchecked cast 警告が発生しなくなれば完了です。