checker/tests/tainting/TaintedIntersections.java

import org.checkerframework.checker.tainting.qual.Tainted;
import org.checkerframework.checker.tainting.qual.Untainted;

public class TaintedIntersections {
  interface MyInterface {}

  void test1() {
    // null is @Untainted
    @Untainted Object o1 = (@Untainted Object & @Untainted MyInterface) null;
    // :: warning: (explicit.annotation.ignored)
    @Untainted Object o2 = (@Untainted Object & @Tainted MyInterface) null;
    // :: error: (assignment) :: warning: (explicit.annotation.ignored)
    @Untainted Object o3 = (@Tainted Object & @Untainted MyInterface) null;
    // :: error: (assignment)
    @Untainted Object o4 = (@Tainted Object & @Tainted MyInterface) null;
  }

  void test2() {
    // null is @Untainted
    @Untainted Object o1 = (@Untainted Object & MyInterface) null;
    @Untainted Object o3 = (Object & @Untainted MyInterface) null;
    // :: error: (assignment)
    @Untainted Object o2 = (Object & @Tainted MyInterface) null;
    // :: error: (assignment)
    @Untainted Object o4 = (@Tainted Object & MyInterface) null;
  }

  void test3(@Tainted MyInterface i) {
    // :: warning: (cast.unsafe)
    @Untainted Object o1 = (@Untainted Object & @Untainted MyInterface) i;
    // :: warning: (explicit.annotation.ignored) :: warning: (cast.unsafe)
    @Untainted Object o2 = (@Untainted Object & @Tainted MyInterface) i;
    // :: error: (assignment) :: warning: (explicit.annotation.ignored)
    @Untainted Object o3 = (@Tainted Object & @Untainted MyInterface) i;
    // :: error: (assignment)
    @Untainted Object o4 = (@Tainted Object & @Tainted MyInterface) i;
  }

  void test4(@Tainted MyInterface i) {
    // :: warning: (cast.unsafe)
    @Untainted Object o1 = (@Untainted Object & MyInterface) i;
    // :: warning: (cast.unsafe)
    @Untainted Object o3 = (Object & @Untainted MyInterface) i;
    // :: error: (assignment)
    @Untainted Object o2 = (Object & @Tainted MyInterface) i;
    // :: error: (assignment)
    @Untainted Object o4 = (@Tainted Object & MyInterface) i;
  }
}