Added documentation for validation-constraints

Author: JohannesRabauer

CHANGELOG.md

@@ -17,7 +17,6 @@
 
 * Auto-Fix problems with adding ids to entities with existing data store.
 
-~~~~
 # 2.3.0
 
 * Add support for shutting down the storage during application shutdown

docs/modules/ROOT/nav.adoc

@@ -9,5 +9,6 @@
 ** xref:features/transactions.adoc[Transactions]
 ** xref:features/versions.adoc[Versions]
 ** xref:features/rest-api.adoc[REST Interface]
+** xref:features/validation-constraints.adoc[Validation Constraints]
 * xref:migration.adoc[Migration from JPA]
 * xref:known-issues.adoc[Known issues]

docs/modules/ROOT/pages/features/features.adoc

@@ -6,3 +6,4 @@
 * xref:features/transactions.adoc[Transactions]
 * xref:features/versions.adoc[Versions]
 * xref:features/rest-api.adoc[REST Interface]
+* xref:features/validation-constraints.adoc[Validation Constraints]

docs/modules/ROOT/pages/features/validation-constraints.adoc

@@ -0,0 +1,19 @@
+= Validation Constraints
+
+By using the https://jakarta.ee/learn/docs/jakartaee-tutorial/current/beanvalidation/bean-validation/bean-validation.html[Jakarta Bean Validation Constraints] developers with {product-name} can easily limit the allowed input of entities.
+Here is a full list of supported validations: https://jakarta.ee/learn/docs/jakartaee-tutorial/current/beanvalidation/bean-validation/bean-validation.html#_using_jakarta_bean_validation_constraints[https://jakarta.ee/learn]
+
+[source,java,title="https://github.com/xdev-software/spring-data-eclipse-store/blob/develop/spring-data-eclipse-store-demo/src/main/java/software/xdev/spring/data/eclipse/store/demo/complex/model/Person.java[Example from complex demo]"]
+----
+package software.xdev.spring.data.eclipse.store.demo.complex.model;
+
+import jakarta.validation.constraints.NotBlank;
+
+public class Person extends BaseEntity
+{
+    @NotBlank
+    private String firstName;
+    //...
+----
+
+The ``jakarta.validation.Validator`` is provided by the https://github.com/xdev-software/spring-data-eclipse-store/tree/develop/spring-data-eclipse-store/src/main/java/software/xdev/spring/data/eclipse/store/repository/config/EclipseStoreClientConfiguration.java[``EclipseStoreClientConfiguration``] and can be changed in the project-specific configuration.