Hello
I think recently the requirement every relationship to be defined
both ways was revoked.
I found few problems with it:
we have defined (to many, read only):
<obj-relationship name="sessions" source="Course" target="Session"
deleteRule="Nullify" db-relationship-path="CourseClasses.sessions"/>
it looks like cayenne creates fake relationship called
runtimeRelationship0 which fails during runtime :
[java] 14:36:38,192 [btpool0-1 ] INFO
org.apache.cayenne.remote.service.BaseRemoteService :157 - error
processing message
[java] java.lang.NoSuchFieldException: runtimeRelationship0
[java] at java.lang.Class.getDeclaredField(Class.java:1854)
[java] at
org.apache.cayenne.reflect.FieldAccessor.lookupFieldInHierarchy
(FieldAccessor.java:154)
[java] at
org.apache.cayenne.reflect.FieldAccessor.lookupFieldInHierarchy
(FieldAccessor.java:163)
[java] at
org.apache.cayenne.reflect.FieldAccessor.lookupFieldInHierarchy
(FieldAccessor.java:163)
[java] at
org.apache.cayenne.reflect.FieldAccessor.prepareField
(FieldAccessor.java:101)
[java] at org.apache.cayenne.reflect.FieldAccessor.<init>
(FieldAccessor.java:50)
[java] at
org.apache.cayenne.reflect.PersistentDescriptorFactory.createAccessor
(PersistentDescriptorFactory.java:191)
[java] at
org.apache.cayenne.reflect.valueholder.ValueHolderDescriptorFactory.crea
teToOneProperty(ValueHolderDescriptorFactory.java:70)
[java] at
org.apache.cayenne.reflect.PersistentDescriptorFactory.getDescriptor
(PersistentDescriptorFactory.java:99)
[java] at
org.apache.cayenne.reflect.PersistentDescriptorFactory.getDescriptor
(PersistentDescriptorFactory.java:51)
[java] at
org.apache.cayenne.reflect.ClassDescriptorMap.createDescriptor
(ClassDescriptorMap.java:122)
as a workaround a reverse relationship can be created (to one, read
only) :
<obj-relationship name="course" source="Session" target="Course" db-
relationship-path="courseClass.course"/>
It does work ok than, with a small problem. We have also customised
the dotemplates (templates to generate the cayenne classes).
within them we are using loop to create a generic setValueForKey(key,
value) method for classes on client (this is an equivalent of
writeProperty(key, value) on server):
#foreach( $rel in ${objEntity.DeclaredRelationships})
#if (!$rel.ToMany)
if (${stringUtils.capitalizedAsConstant($rel.Name)}
_PROPERTY.equals(key)) { set${stringUtils.capitalized($rel.Name)}( ($
{importUtils.formatJavaType($rel.TargetEntity.ClientClassName)})
value); return; }
#end
#end
but we don't want to iterate through the "read-only" relationships.
Any hint how to do that ?
Marcin
