Now imagine that we want to retrieve the person's name attributes only.
What means does Spring Data offer to achieve this?The rest of this chapter answers that question.
What means does Spring Data offer to achieve this?The rest of this chapter answers that question.
[[projections.interfaces]]
== Interface-based Projections
@ -264,17 +264,22 @@ class NamesOnly {
@@ -264,17 +264,22 @@ class NamesOnly {
You can dramatically simplify the code for a DTO by using https://projectlombok.org[Project Lombok], which provides an `@Value` annotation (not to be confused with Spring's `@Value` annotation shown in the earlier interface examples).
If you use Project Lombok's `@Value` annotation, the sample DTO shown earlier would become the following:
[source,java]
[source,java]
----
@Value
class NamesOnly {
String firstname, lastname;
}
----
Fields are `private final` by default, and the class exposes a constructor that takes all fields and automatically gets `equals(…)` and `hashCode()` methods implemented.
@ -284,7 +289,7 @@ To apply dynamic projections, use a query method such as the one shown in the fo
@@ -284,7 +289,7 @@ To apply dynamic projections, use a query method such as the one shown in the fo
.A repository using a dynamic projection parameter