java - Getter for mutable object -


i read many articles how write right getter/ setter mutable object date or array. when changed on 

    public date getdateto() {         return (date) dateto.clone();     }      public void setdateto(date dateto) {         this.dateto = (date) dateto.clone();     }

i java.lang.nullpointerexception. means shoul initialize date in (post)constructor?

it dateto not constructed, there nothing clone. answer yes - should initialize it.


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