Jasper if condition

I have a BigDecimal variable that contains number with minus(-) and not. I want to put static text that should be match with this conditions:

• If $V{saldo} contains minus (-) value The static text will show "Rugi"
• If $V {saldo} doesnt's contain minus(-) value the static text will show "Laba"

For example, if $V{saldo} = -250000 then the static text should be "Rugi", and if $V{saldo} = 400000 then the static text should be "Laba"

Can anyone help me?? Thanks