java - Reflection finding method with Generic Type withing Parameterized Class -

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i have class following signature:

public class multiplesorting<t extends enum<?>> {     private class<t> criteriatype;     private t selectedcriteria;      public multiplesorting(class<t> criteriatype) {         super();         this.criteriatype = criteriatype;     }          public void setselectedcriteria(t selectedcriteria) {         this.selectedcriteria = selectedcriteria;     }      public t getselectedcriteria() {         return selectedcriteria;     }      public class<t> getcriteriatype(){         return criteriatype;     }      public void setcriteriatype(class<t> criteriatype){         this.criteriatype = criteriatype;     } }

i instantiating new multiplesorting(articlesortfield.class);. here articlesortfield enum. method within multiplesorting when trying method setselectedcriteria through reflection as:

method setselectedcriteriamethod = getclass().getdeclaredmethod("setselectedcriteria",getcriteriatype());

the setselectedcriteriamethod returning null. after debugging found getcriteriatype() returning class articledortfield argument type of setselectedcriteria method enum, why reflection returning null.

also if change signature of multiplesorting public class multiplesorting<t> t of setselectedcriteria becoming object.

  • how can fix issue?
  • is happening due type erasure? thought t replaced articledortfield. couldn't understand why behaving this. how type erasure works? replace generic type concrete implementation?

any pointer helpful me.

a possible fix issue might "setselectedcriteria" method calling getclass().getdeclaredmethod(...) desired type, super type, , walking class hierarchy until found matching method. it's not beautiful solution might trick.

and yes, caused type erasure. once code compiled, there no <t> object, there no <t extends enum<?>> enum. type safety checked compiler, not enforced jvm.


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