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-68abff8f14df7378153577/] 2). Implement prespecified interfaces, as in [crayon-68abff8f14e0f779373521/] 3). Contain prespecified annotations, as in [crayon-68abff8f14e13167231832/] sumber: wiki 185