/**
* Returns an existing join for the given attribute if one already exists or creates a new one if
* not.
*
* @param from the {@link From} to get the current joins from.
* @param attribute the {@link Attribute} to look for in the current joins.
* @return will never be {@literal null}.
*/
private static Join<?, ?> getOrCreateJoin(From<?, ?> from, String attribute) {
for (Join<?, ?> join : from.getJoins()) {
boolean sameName = join.getAttribute().getName().equals(attribute);
if (sameName && join.getJoinType().equals(JoinType.LEFT)) {
return join;
}
}
return from.join(attribute, JoinType.LEFT);
}
@SuppressWarnings({"unchecked"})
private void renderJoins(
StringBuilder jpaqlQuery, RenderingContext renderingContext, Collection<Join<?, ?>> joins) {
if (joins == null) {
return;
}
for (Join join : joins) {
((FromImplementor) join).prepareAlias(renderingContext);
jpaqlQuery
.append(renderJoinType(join.getJoinType()))
.append(((FromImplementor) join).renderTableExpression(renderingContext));
renderJoins(jpaqlQuery, renderingContext, join.getJoins());
renderFetches(jpaqlQuery, renderingContext, join.getFetches());
}
}
