There are two types of JSA.
If you've paid sufficient Class 1 National Insurance contributions you can claim contribution-based JSA. (Class 1 contributions are only paid by employees. The Class 2 and Class 4 contributions paid by self-employed people don't count towards contribution-based JSA). This form of JSA does not depend upon your circumstances (such as your savings or your partner's income). Contribution-based JSA can be paid for up to 6 months.
Anyone who's ineligible for contribution-based JSA can be considered for income-based JSA. The big difference, though, is that your circumstances are taken into account. If you've got savings of over �6000 your entitlement will be reduced. (If your savings exceed �16000 you won't get income-based JSA). If your partner works for at least 24 hours each week, you won't get this form of JSA. (If he or she works for less than 24 hours, your entitlement will probably be reduced):
http://www.direct.gov.uk/en/MoneyTaxAndBenefit s/BenefitsTaxCreditsAndOtherSupport/Employedor lookingforwork/DG_10018757
Chris