From 9dc5ca602c8a657bdd4872871038c7b90307cc9b Mon Sep 17 00:00:00 2001
From: rob bygrave <robin.bygrave@gmail.com>
Date: Mon, 14 May 2018 21:32:48 +1200
Subject: [PATCH] #1372 - Missing @OneToOne mapping yields unusable error
 messages.

---
 .../io/ebeaninternal/server/deploy/BeanPropertyAssocOne.java  | 4 ++++
 src/test/java/org/tests/model/basic/OrderAggregate.java       | 2 +-
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/main/java/io/ebeaninternal/server/deploy/BeanPropertyAssocOne.java b/src/main/java/io/ebeaninternal/server/deploy/BeanPropertyAssocOne.java
index 4cea3315a..25f84abe1 100644
--- a/src/main/java/io/ebeaninternal/server/deploy/BeanPropertyAssocOne.java
+++ b/src/main/java/io/ebeaninternal/server/deploy/BeanPropertyAssocOne.java
@@ -310,6 +310,10 @@ public class BeanPropertyAssocOne<T> extends BeanPropertyAssoc<T> implements STr
         String discProperty = prefix + "." + discriminatorColumn;
         selectChain.add(discProperty);
       }
+      if (targetIdBinder == null) {
+        throw new IllegalStateException("No Id binding property for " + getFullBeanName()
+          + ". Probably a missing @OneToOne mapping annotation on this relationship?");
+      }
       targetIdBinder.buildRawSqlSelectChain(prefix, selectChain);
 
     } else {
diff --git a/src/test/java/org/tests/model/basic/OrderAggregate.java b/src/test/java/org/tests/model/basic/OrderAggregate.java
index 364d94f2f..f67614b35 100644
--- a/src/test/java/org/tests/model/basic/OrderAggregate.java
+++ b/src/test/java/org/tests/model/basic/OrderAggregate.java
@@ -16,7 +16,7 @@ import javax.persistence.OneToOne;
 @Sql
 public class OrderAggregate {
 
-  @OneToOne
+  //@OneToOne
   Order order;
 
   Double maxAmount;