Java Generics Copy Constructor -

i'm wanting code copy constructor generically defined class. have inner class node, going use nodes binary tree. when pass in a new object

public class treedb <t extends object> {     //methods , such      public t patient;      patient = new t(patient2);       //this line throwing error     //where patient2 of type <t> } 

i don't know how generically define copy constructor.

t can't guarantee class represents have required constructor can't use new t(..) form.

i not sure if need if sure class of object want copy have copy constructor can use reflection like

public class test<t> {      public t createcopy(t item) throws exception {// here should         // thrown more detailed exceptions decided reduce them         // readability          class<?> clazz = item.getclass();         constructor<?> copyconstructor = clazz.getconstructor(clazz);          @suppresswarnings("unchecked")         t copy = (t) copyconstructor.newinstance(item);          return copy;     } } 

//demo myclass have copy constructor:  //         public myclass(myclass original) public static void main(string[] args) throws exception {     myclass mc = new myclass("somestring", 42);      test<myclass> test = new test<>();     myclass copy = test.createcopy(mc);      system.out.println(copy.getsomestring());     system.out.println(copy.getsomenumber()); }