java - 过滤列表的属性不包含在另一个列表的属性中

Question

public class Bill {
    private Long code;

    public Bill(Long code) {
        this.code = code;
    }
    // setters and Getters
}

class Detail {
    private BillId billId;

    public Detail(BillId billId) {
        this.billId = billId;
    }
    // setters and Getters

}

class BillId {
    private Long number;
    private Long code;

    public BillId(Long number, Long code) {
        this.number = number;
        this.code = code;
    }
    // setters and Getters
}

现在我有了

List<Bill> listBill = new ArrayList<>();
listBill.add(new Bill(1L));
listBill.add(new Bill(2L));
listBill.add(new Bill(3L));
listBill.add(new Bill(4L));
listBill.add(new Bill(5L));
listBill.add(new Bill(6L));


List<Detail> listDetail = new ArrayList<>();
listDetail.add(new Detail(new BillId(1000L, 10L)));
listDetail.add(new Detail(new BillId(1000L, 2L)));
listDetail.add(new Detail(new BillId(2000L, 30L)));
listDetail.add(new Detail(new BillId(2000L, 4L)));
listDetail.add(new Detail(new BillId(3000L, 50L)));
listDetail.add(new Detail(new BillId(3000L, 6L)));

现在我需要一个新列表，从listBill获取项目，其中某些项目与listDetail中的某些项目不匹配

detail.getBillId ().getCode() not match with bill.getCode()

预期列表对于新内容抱歉!

newListBill.add(new Bill(1L)); 
newListBill.add(new Bill(3L));
newListBill.add(new Bill(5L));

Answer 1

使用流API:

listBill.stream()
.filter( b -> !listDetail.stream()
     .anyMatch( d -> d.getBillId().getCode() == b.getCode() ) )
.collect( Collectors.toList() );