Explain Criteria API ?

Criteria is a simplified API for retrieving entities by composing Criterion objects. This is a very convenient approach for functionality like "search" screens where there is a variable number of conditions to be placed upon the result set.

List employees = session.createCriteria(Employee.class)
                          .add(Restrictions.like("name", "a%") )
                          .add(Restrictions.like("address", "Boston"))
                          .addOrder(Order.asc("name") )
                          .list();