protected Object clone() 克隆方法
    补充: 子类覆写父类的方法 子类覆写的方法返回值要和父类一样活着
    子类方法的返回值类型是父类对应方法返回值类型的子类型image.png 要被克隆的对象对应的类 必须实现Cloneable

    1.         Cloneable接口: 一个标记接口!!  类似于电影票<br />            标记接口:<br />                    该接口没有任何东西 是一种标记
    3.     CloneNotSupportedException clone接口没有被应用异常<br />  要被克隆的对象对应的类必须实现Cloneable接口<br />![image.png](https://cdn.nlark.com/yuque/0/2022/png/28889470/1654684907668-d3c501c1-04c4-405b-8228-f3bd30093c87.png#clientId=ua3b7c389-8690-4&crop=0&crop=0&crop=1&crop=1&from=paste&height=260&id=u801983e3&margin=%5Bobject%20Object%5D&name=image.png&originHeight=325&originWidth=951&originalType=binary&ratio=1&rotation=0&showTitle=false&size=41781&status=done&style=none&taskId=u40d53c79-cdc9-4ce6-956b-305bb5c7d35&title=&width=760.8)<br />![image.png](https://cdn.nlark.com/yuque/0/2022/png/28889470/1654685084503-75eef754-1b9f-41d6-9a16-53b4024473e5.png#clientId=ua3b7c389-8690-4&crop=0&crop=0&crop=1&crop=1&from=paste&height=53&id=u1b3196d7&margin=%5Bobject%20Object%5D&name=image.png&originHeight=66&originWidth=450&originalType=binary&ratio=1&rotation=0&showTitle=false&size=4471&status=done&style=none&taskId=u5c1d8c9b-be20-4dbc-8eda-7e393b1b647&title=&width=360)<br />![image.png](https://cdn.nlark.com/yuque/0/2022/png/28889470/1654685117576-ccab2691-c83d-4e34-b482-305b0ef22a66.png#clientId=ua3b7c389-8690-4&crop=0&crop=0&crop=1&crop=1&from=paste&height=354&id=u1d161cde&margin=%5Bobject%20Object%5D&name=image.png&originHeight=443&originWidth=854&originalType=binary&ratio=1&rotation=0&showTitle=false&size=50855&status=done&style=none&taskId=ubc4ba030-7816-4fbf-91cb-2230d6003f5&title=&width=683.2)