$expand with $count fails when having a join table issue still exists on version 2.3.0(opened earlier as #376 and closed as fixed)

[dbhandari555]

odata-jpa version : 2.3.0

Issue summary:
When the criteria builder supplied is other than ProcessorCriteriaBuilder(For example: Hibernate's SqmCriteriaNodeBuilder), JPAExpandJoinCountQuery's count() method gets invoked. To start with, it fails with NPE when constructing from clause because of target not being set in JPAAbstractJoinQuery. If you get past that by explicitly setting the target to root, buildExpandJoinPath fails with error when getting columns list since there is only one column supplied.

Technical details:
First error: NPE
private void createCountFrom(CriteriaQuery countQuery) throws ODataApplicationException {
HashMap<String, From> joinTables = new HashMap();
this.createFromClauseRoot(countQuery, joinTables);
this.createFromClauseNavigationJoins(joinTables);
this.lastInfo.setFromClause(this.target);
}
createFromClauseRoot does not set the target in JPAAbstractJoinQuery causing NPE when executing createFromClauseNavigationJoins

Once fixed,
this.buildExpandJoinPath(this.target); results in "com.sap.olingo.jpa.processor.core.exception.ODataJPAQueryException: ON condition right attribute is null / not found." at this.association.getJoinColumnsList().

[dbhandari555]

@wog48 Was there a fix for this scenario in 2.2.0?

[wog48]

I was able to reproduce the problem

[wog48]

I have created a new release, which shall solve the issue.