Ideally speaking, a POJO is a Java object not bound by any restriction other than those forced by the Java Language Specification; i.e. a POJO should not have to 1). Extend prespecified classes, as in [crayon-6869f85b21c81813554702/] 2). Implement prespecified interfaces, as in [crayon-6869f85b21ca6630976529/] 3). Contain prespecified annotations, as in [crayon-6869f85b21cab419367762/] sumber: wiki 185