relation constructor should fail fast for null values to track down non-standard initialization (e.g. JSON libs)

Author: greenrobot

objectbox-java/src/main/java/io/objectbox/relation/ToMany.java

@@ -74,6 +74,12 @@ public class ToMany<TARGET> implements List<TARGET>, Serializable {
  transient private boolean removeFromTargetBox;
 
  public ToMany(Object sourceEntity, RelationInfo<TARGET> relationInfo) {
+ if(sourceEntity == null ) {
+ throw new IllegalArgumentException("No source entity given (null)");
+ }
+ if(relationInfo == null) {
+ throw new IllegalArgumentException("No relation info given (null)");
+ }
  this.entity = sourceEntity;
  this.relationInfo = relationInfo;
  }

objectbox-java/src/main/java/io/objectbox/relation/ToOne.java

@@ -55,6 +55,12 @@ public class ToOne<TARGET> implements Serializable {
  * @param relationInfo Meta info as generated in the Entity_ (entity name plus underscore) classes.
  */
  public ToOne(Object sourceEntity, RelationInfo relationInfo) {
+ if(sourceEntity == null ) {
+ throw new IllegalArgumentException("No source entity given (null)");
+ }
+ if(relationInfo == null) {
+ throw new IllegalArgumentException("No relation info given (null)");
+ }
  this.entity = sourceEntity;
  this.relationInfo = relationInfo;
  virtualProperty = relationInfo.targetIdProperty == null;