checker/tests/calledmethods/Generics.java

import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.stream.Stream;
import org.checkerframework.checker.calledmethods.qual.*;
import org.checkerframework.common.returnsreceiver.qual.*;

public class Generics {

  static interface Symbol {

    boolean isStatic();

    void finalize(@CalledMethods("isStatic") Symbol this);
  }

  static List<@CalledMethods("isStatic") Symbol> makeList(Symbol s) {
    s.isStatic();
    ArrayList<@CalledMethods("isStatic") Symbol> l = new ArrayList<>();
    l.add(s);
    return l;
  }

  static void useList() {
    Symbol s = null;
    for (Symbol t : makeList(s)) {
      t.finalize();
    }
  }

  // reduced from real-world code
  private <@CalledMethods() T extends Symbol> T getMember(Class<T> type, boolean b) {
    if (b) {
      T sym = getMember(type, !b);
      if (sym != null && sym.isStatic()) {
        return sym;
      }
    } else {
      T sym = getMember(type, b);
      if (sym != null) {
        return sym;
      }
    }
    return null;
  }

  static Stream<String> stringList() {
    String s = "hi";
    // dummy method call
    s.contains("h");
    // should infer type Stream<@CalledMethods() String>
    return Arrays.asList(s).stream();
  }
}