/**
* removing parents and children
*
* @param parentId record id
* @param childId record id
*/
private void removePath(Long parentId, Long childId) {
EntityManager em = mc.getTransactionEntityManager();
// -- building branch to remove from below hierarchy >> using parent to use only this parent
// path if more than one exists
List<Long> pathList =
em.createQuery(
"SELECT rp.recordPK.path FROM RecordPath rp WHERE rp.recordPK.child = :child")
.setParameter("child", parentId)
.getResultList();
pathList.add(parentId);
// -- retrieving hierarchies to complete with new branch >> finding all children of reference
List<RecordPathPK> pkList =
em.createQuery("SELECT rp.recordPK FROM RecordPath rp WHERE rp.recordPK.path = :path")
.setParameter("path", childId)
.getResultList();
pkList.add(new RecordPathPK(parentId, childId, parentId));
// -- applying path branch to childrens
for (RecordPathPK pk : pkList) {
for (Long path : pathList) {
pk.setPath(path);
em.remove(em.getReference(RecordPath.class, pk));
}
}
}
/**
* Logic removing the record as well as the links. Multiple trials are preserved in comments just
* for reminder on current reference implementation.
*
* @param <T> POJOs must extend DefaultRecord
* @param recordList list of records to remove
*/
private <T extends Record> void removeTransaction(List<T> recordList) {
// String recordType = records.get(0).getClass().getName();
// -- extracting IDs for batch processing
ArrayList<Long> idList = new ArrayList<>();
for (Record record : recordList) {
idList.add(record.getId());
// -- POSTGRES won't perform correctly with multiple delete query
// mc.getEntityManager().createNamedQuery("RecordLink.deleteByRecordId").setParameter("record", record.getId()).executeUpdate();
// mc.getEntityManager().createNamedQuery("RecordWrapper.deleteByRecordId").setParameter("record", record.getId()).executeUpdate();
// record.setId(null);
// ------------------------------------------------------------------
}
// -- DELETE query less efficient than JPA remove (= batch) by x3
// mc.getEntityManager().createNamedQuery("RecordLink.deleteByRecordIdList").setParameter("list", idList).executeUpdate();
// mc.getEntityManager().createNamedQuery("RecordWrapper.deleteByRecordIdList").setParameter("list", idList).executeUpdate();
// ----------------------------------------------------------------------
EntityManager em = mc.getTransactionEntityManager();
// -- removing links
// -- two queries to fetch links is more efficient than a single with OR by x10
// -- CursoredStream is effective in memory management and helps to get better performances than
// EAGER fetch
CursoredStream pkList1 =
(CursoredStream)
em.createNamedQuery("RecordLink.findByReferenceIdList")
.setParameter("list", idList)
.setHint("eclipselink.cursor", true)
.getSingleResult();
CursoredStream pkList2 =
(CursoredStream)
em.createNamedQuery("RecordLink.findByLinkIdList")
.setParameter("list", idList)
.setHint("eclipselink.cursor", true)
.getSingleResult();
// -- using reference to avoid complete loading of obsolete objects
while (!pkList1.atEnd()) {
for (Object pkO : pkList1.next(100)) {
RecordLinkPK pk = (RecordLinkPK) pkO;
em.remove(em.getReference(RecordLink.class, pk));
auditor.logRemoveLink(pk.getReference(), pk.getLink());
}
}
pkList1.close();
while (!pkList2.atEnd()) {
for (Object pkO : pkList2.next(100)) {
RecordLinkPK pk = (RecordLinkPK) pkO;
em.remove(em.getReference(RecordLink.class, pk));
// no log here as duplicated
}
}
pkList2.close();
// -- removing paths
List<RecordPathPK> childList =
em.createNamedQuery("RecordPath.findChildFromIdList")
.setParameter("list", idList)
.getResultList();
for (RecordPathPK path : childList) {
removePath(path.getParent(), path.getChild());
auditor.logRemovePath(path.getParent(), path.getChild());
}
List<RecordPathPK> parentList =
em.createNamedQuery("RecordPath.findParentFromIdList")
.setParameter("list", idList)
.getResultList();
for (RecordPathPK path : parentList) {
removePath(path.getParent(), path.getChild());
auditor.logRemovePath(path.getParent(), path.getChild());
}
// -- removing indexes
List<RecordIndexPK> indexList =
em.createNamedQuery("RecordIndex.findIndexFromIdList")
.setParameter("list", idList)
.getResultList();
indexList
.stream()
.forEach(
(index) -> {
em.remove(em.getReference(RecordIndex.class, index));
});
// -- removing records
for (Long id : idList) {
RecordWrapper rw = em.getReference(RecordWrapper.class, id);
em.remove(rw);
auditor.logRemoveRecord(rw);
}
}