--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/main/java/de/intevation/lada/validation/rules/messung/HasMesswert.java	Fri Mar 13 16:50:20 2015 +0100
@@ -0,0 +1,42 @@
+package de.intevation.lada.validation.rules.messung;
+
+import java.util.List;
+
+import javax.inject.Inject;
+
+import de.intevation.lada.model.land.LMessung;
+import de.intevation.lada.model.land.LMesswert;
+import de.intevation.lada.util.annotation.RepositoryConfig;
+import de.intevation.lada.util.data.QueryBuilder;
+import de.intevation.lada.util.data.Repository;
+import de.intevation.lada.util.data.RepositoryType;
+import de.intevation.lada.util.rest.Response;
+import de.intevation.lada.validation.Violation;
+import de.intevation.lada.validation.annotation.ValidationRule;
+import de.intevation.lada.validation.rules.Rule;
+
+@ValidationRule("Messung")
+public class HasMesswert implements Rule {
+
+    @Inject
+    @RepositoryConfig(type=RepositoryType.RO)
+    private Repository repo;
+
+    @Override
+    public Violation execute(Object object) {
+        LMessung messung = (LMessung)object;
+        QueryBuilder<LMesswert> builder =
+            new QueryBuilder<LMesswert>(
+                repo.entityManager("land"), LMesswert.class);
+        builder.and("messungsId", messung.getId());
+        Response response = repo.filter(builder.getQuery(), "land");
+        @SuppressWarnings("unchecked")
+        List<LMesswert> messwerte = (List<LMesswert>)response.getData();
+        if (messwerte == null || messwerte.isEmpty()) {
+            Violation violation = new Violation();
+            violation.addWarning("messwert", 631);
+            return violation;
+        }
+        return null;
+    }
+}