Major Description
Given an entity class A which owns a OneToOne entity of class B, and given a cascade on that OneToOne that includes DELETE, an attempt to bulk-delete A when using the DataCache results in a stack trace like the following:
java.lang.ClassCastException: org.apache.openjpa.datacache.QueryCacheStoreQuery cannot be cast to org.apache.openjpa.kernel.ExpressionStoreQuery
at org.apache.openjpa.kernel.ExpressionStoreQuery$DataStoreExecutor.executeQuery(ExpressionStoreQuery.java:674)
at org.apache.openjpa.kernel.QueryImpl.execute(QueryImpl.java:979)
at org.apache.openjpa.kernel.QueryImpl.deleteInMemory(QueryImpl.java:1005)
... 28 more
The proximate cause for the bug is that when the JDBCStoreQuery does this:
private Table getTable(FieldMapping fm, Table table) {
if (fm.getCascadeDelete() != ValueMetaData.CASCADE_NONE)
return INVALID;
it causes "isSingleTableMapping" to be considered false, which in turn permits executeBulkOperation to return null. Meanwhile, back in DataStoreExecutor:
public Number executeDelete(StoreQuery q, Object[] params)
{ Number num = ((ExpressionStoreQuery) q).executeDelete(this, _meta, _metas, _subs, _facts, _exps, params); if (num == null) return q.getContext().deleteInMemory(this, params); // <- now we have come here because executeDelete punted return num; }So deleteInMemory gets called in QueryImpl:
public Number deleteInMemory(StoreQuery.Executor executor,
Object[] params) {
try {
Object o = execute(executor, params);
, but a DataStoreExecutor doesn't know how to execute the QueryCacheStoreQuery that it gets.
Somehwere, something is too unwrapped, or not wrapped enough. Good luck!
Workaround:
If A owns B, then instead of cascade=CascadeType.ALL, you can
@Entity
class A {
B myThing;
@OneToOne(cascade =
{ CascadeType.PERSIST, CascadeType.MERGE, CascadeType.REFRESH })
B getMyThing()
}
@Entity
class B {
A owner;
@ForeignKey(deleteAction=ForeignKeyAction.CASCADE)
A getOwner()
}