Java - Inheritance - Can you return a child self into parent instance method that returns self? -


this question has answer here:

i have own custom list has bunch of functionality since manipulating same kinds of lists wanted extend custom list defined type , want able use parent functions , return child type.

example:

//object within list public class childobject {      private string name;      // getters, setters, methods, etc. }   // parent custom list public class parentlist<t> extends arraylist<t> {      public parentlist<t> filter(predicate<t> predicate) {         collector<t, ?, list<t>> collector = collectors.tolist();          list<t> temp = this.stream().filter(predicate).collect(collector);          this.clear();         this.addall(temp);          return this;     } }  // extended custom list predefined type public class childlist extends parentlist<childobject> {      // other methods }  // implementation public static void main(string[] args) {      childobject = new childobject("alice");     childobject b = new childobject("bob");      childlist filterlist = new childlist();     filterlist.add(a);     filterlist.add(b);      filterlist.filter(c -> childobject.getname().equals("alice")); }

it nice if possible feel free chime in whether doable, practical, or have thoughts on performance issues or bad practices.

i did figure out solution want know if way make work without following solution:

// extended custom list predefined type public class childlist extends parentlist<childobject> {      public childlist filter(predicate<childobject> predicate) {         super.filter(predicate);          return this;     }      // other methods }

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