Usage of @Transient annotated field

Support
#1

Very new to Cuba, apologies if this is a simple issue.

I have a very simple invoice / invoice line composition that worked fine until I added the following transient linePrice property.


    @Column(name = "QUANTITY", nullable = false)
    protected Integer quantity;

    @Column(name = "UNIT_PRICE", nullable = false)
    protected BigDecimal unitPrice;

    @Transient
    @MetaProperty(related = {"quantity", "unitPrice"})
    protected BigDecimal linePrice;

    public BigDecimal getLinePrice() {
        return getUnitPrice().multiply(BigDecimal.valueOf(getQuantity()));
    }

I added linePrice to my view but whenever I try to edit I get a NullPointerException pointing to the “return” line in getLinePrice.

Any pointers appreciated.

#2

Probably it is because the fields are null when the object is just created in memory. Try to initialize the fields:

@Column(name = "QUANTITY", nullable = false)
protected Integer quantity = 0;

@Column(name = "UNIT_PRICE", nullable = false)
protected BigDecimal unitPrice = BigDecimal.ZERO;

@Transient
@MetaProperty(related = {"quantity", "unitPrice"})
protected BigDecimal linePrice;

public BigDecimal getLinePrice() {
    return getUnitPrice().multiply(BigDecimal.valueOf(getQuantity()));
}