Java – querydsl – subquery in set expression

I use spring data JPA and querydsl (3.2.3)

My simplified model is as follows:

@Entity
public class Invoice {
    @ManyToOne
    private supplier supplier;
}

@Entity
public class supplier {
    private String number;
}

@Entity
public class Company {
    private String number;
    private boolean active
}

Now, what I'm trying to do is this query:

SELECT * FROM Invoice WHERE invoice.supplier.number in (SELECT number from Company where active=true)

So basically, I need to make a sub query in the collectionexpression, such as format, to get all the company numbers and set them as an in () expression

My spring database implements customquerydsljparepository, which extends jparepository and querydslpredicateexecutor I hope the answer is straightforward, but I'm new to querydsl and haven't found a solution so far

Solution

This is a variant of jaiwo99, more in the form of jpaesque

BooleanExpression exp = invoice.supplier.number.in(new JPASubQuery()
    .from(company)
    .where(company.active.isTrue())
    .list(company.nu‌​mber));

Randomly merge them into the original answer