関連ワード:  what is class in java and object    what is object class in java with example    what is objectmapper class in java    what is java class and object explain its features    what is object class in java programming language    what is class and object in java explain with example    what is class and object in java oops    what is class and object in java with realtime examples    what is class and object in java program    what is class and object in java javatpoint