Hacking.

Author: odrotbohm

server/pom.xml

@@ -20,6 +20,7 @@ xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/ma
 		<datasource-micrometer.version>2.1.1</datasource-micrometer.version>
 		<java.version>25</java.version>
 		<jmolecules.version>2025.0.2</jmolecules.version>
+		<spring-data-bom.version>2026.0.0-SNAPSHOT</spring-data-bom.version>
 		<spring-modulith.version>2.1.0-SNAPSHOT</spring-modulith.version>
 
 		<!-- Enable full annotation processing on Java 23+ -->

server/src/main/java/de/odrotbohm/restbucks/dashboard/Dashboard.java

@@ -27,8 +27,12 @@
 
 import org.javamoney.moneta.Money;
 import org.springframework.data.rest.webmvc.RepositoryLinksResource;
+import org.springframework.data.rest.webmvc.support.ETag;
 import org.springframework.hateoas.server.RepresentationModelProcessor;
+import org.springframework.http.HttpStatus;
 import org.springframework.modulith.events.ApplicationModuleListener;
+import org.springframework.web.ErrorResponse;
+import org.springframework.web.bind.annotation.ExceptionHandler;
 import org.springframework.web.bind.annotation.GetMapping;
 import org.springframework.web.bind.annotation.RestController;
 
@@ -58,6 +62,16 @@ void on(OrderPaid event) {
 		this.revenue = revenue.add(event.total());
 	}
 
+	@GetMapping("/exception")
+	void exception() {
+		throw new IllegalArgumentException();
+	}
+
+	@ExceptionHandler
+	ErrorResponse handle(IllegalArgumentException exception, ETag etag) {
+		return ErrorResponse.builder(exception, HttpStatus.NOT_ACCEPTABLE, "Boo!").build();
+	}
+
 	/*
 	 * (non-Javadoc)
 	 * @see org.springframework.hateoas.server.RepresentationModelProcessor#process(org.springframework.hateoas.RepresentationModel)