spring-framework

Spring Framework

Sam Brannen 68fce29ae9 Support Optional with null-safe and Elvis operators in SpEL expressions This commit introduces null-safe support for java.util.Optional in the following SpEL operators: - PropertyOrFieldReference - MethodReference - Indexer - Projection - Selection - Elvis Specifically, when a null-safe operator is applied to an empty `Optional`, it will be treated as if the `Optional` were `null`, and the subsequent operation will evaluate to `null`. However, if a null-safe operator is applied to a non-empty `Optional`, the subsequent operation will be applied to the object contained in the `Optional`, thereby effectively unwrapping the `Optional`. For example, if `user` is of type `Optional<User>`, the expression `user?.name` will evaluate to `null` if `user` is either `null` or an empty `Optional` and will otherwise evaluate to the `name` of the `user`, effectively `user.get().getName()` for property access. Note, however, that invocations of methods defined in the `Optional` API are still supported on an empty `Optional`. For example, if `name` is of type `Optional<String>`, the expression `name?.orElse('Unknown')` will evaluate to "Unknown" if `name` is an empty `Optional` and will otherwise evaluate to the `String` contained in the `Optional` if `name` is a non-empty `Optional`, effectively `name.get()`. Closes gh-20433		9 months ago
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assets/images	…
examples	Use include-code Macro	3 years ago
pages	Support Optional with null-safe and Elvis operators in SpEL expressions	9 months ago
partials/web	Fix typo in reference documentation	1 year ago
nav.adoc	Document programmatic bean registration	10 months ago