Hi,

I currently have a Java class which defines an order table and all order_lines (another table sorted by a sequence, and color) for that table. I use a Java List to return all of the order_lines rows and use the List index values as a reference. I need to make sure these index values remain constant even though new rows are added. There is also a status value on each order_line which is set to AVAILABLE if the line is new and IN_PROGRESS if the line has been processed. I would like to be able to return a list which contains only lines where the status is IN_PROGRESS. Some ideas I had are: (1) add a method in the Order Java class (not sure how to do this), (2) create an external query to return the list, or (3) change from List to another collection. What is the best way accomplish this?

Regards,
Rick

@Entity
@Table(name = "order_header")
public class Order {
private long id;
private List<OrderLine> lines = new ArrayList<OrderLine>();

@Id(generate = GeneratorType.AUTO)
public long getId() {
return id;
}
public void setId(long id) {
this.id = id;
}

@OneToMany(cascade = CascadeType.ALL)
@JoinColumn(name = "order_header_id")
@OrderBy("Sequence, Color")
public List<OrderLine> getLines() {
return lines;
}
public void setLines(List<OrderLine> lines) {
this.lines = lines;
}


// What is the best way to return List<OrderLine> as "select o from OrderLine where order_header_id = ? and status > AVAILABLE"?
// The elements returned in this List need to be modifiable.
...
}


@Entity
@Table(name = "order_line")
public class OrderLine {
private long id;
private String lineNo;

public enum Status {
AVAILABLE, IN_PROGRESS, SKIPPED }

private Status status = Status.AVAILABLE;

@Id(generate = GeneratorType.AUTO)
public long getId() {
return id;
}

public void setId(long id) {
this.id = id;
}

@Column(name = "line_no")
public String getLineNo() {
return lineNo;
}

public void setLineNo(String lineNo) {
this.lineNo = lineNo;
}

@Column(name = "status")
public Status getStatus() {
return status;
}

public void setStatus(Status status) {
this.status = status;
}

...
}

Here are two ways:

write a method to filter the results from getLines:



Alternatively, you can do it in the mapping, with a where clause, but this duplicates the mapping logic (which I am not a fan of) and you may have to return a set rather than a list (and then sort into a list) since the index column will not be contiguous.

Hi,

I tried using the following method:

@Transient
public List<PickingOrderLine> getLinesInProgress() {
return new ArrayList<PickingOrderLine>(CollectionUtils.select(getLines(), new InProgressPredicate()));
}

and the following predicate class:

public class InProgressPredicate implements Predicate {
public boolean evaluate(Object object) {
return true;
}
}

The result from getLinesInProgress() is an empty list (even though there are rows in getLines(). I earlier tried this routine and it also returned an empy list.

@Transient
public List<PickingOrderLine> getLinesInProgress() {
List<PickingOrderLine> l = new ArrayList<PickingOrderLine>();
for (int i = 0; i < getLines(); i++) {
l.add(getLines().get(i));
}
return l;
}

Regards,
Rick

what's getLines().size()?

getLines().size() = 0

It seems that I replaced too may calls to getLines with getLinesInProgress and it was not inserting the records into the DB. So, now it seems to be working. Thanks!!