java - Why does reflection return two methods, when there is only one implementation? -


suppose have code:

public interface address {     public int getno(); }  public interface user<t extends address> {     public string getusername();     public t getaddress();     }  public class addressimpl implements address {     private int no;     public int getno() {         return no;     }     public void setno(int no) {         this.no = no;     } }  public class userimpl implements user<addressimpl> {     private string username;     private addressimpl addressimpl;      public string getusername() {         return username;     }     public void setusername(string username) {         this.username = username;     }      public addressimpl getaddress() {         return addressimpl;     }      public void setaddress(addressimpl addressimpl) {         this.addressimpl = addressimpl;     } }

running code:

int getaddressmethodcount = 0; (method method : userimpl.class.getmethods()) {     if (method.getname().startswith("getaddress")) {         getaddressmethodcount++;     } }

would yield 2 getaddressmethodcount variable; why so?

it's way covariant return types implemented. javap -private show more conveniently reflection.

the subclass have synthetic bridge method handles forwarding more specific method. far jvm concerned methods have name, sequence of raw typed parameters , raw type return. can overload on return type in bytecode.

a system.err.println(mehtod.getreturntype()); should give different results 2 methods.


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