what is meant by dao class in java
Data access object In the non specific context of the Java programming language, Data Access Objects as a design concept can be implemented in a number of ways. This can range from a fairly simple interface that separates the data access parts from the application logic, to frameworks and commercial products. DAO coding paradigms can require some skill. Technologies like Java Persistence API and Enterprise JavaBeans come built into application servers and can be used in applications that use a JavaEE application server. Commercial products like TopLink are available based on Object-relational mapping (ORM). Popular open source ORM products include Doctrine, Hibernate, iBATIS and JPA implementations such as Apache OpenJPA.