@org.checkerframework.framework.qual.DefaultQualifier( org.checkerframework.checker.nullness.qual.Nullable.class) public class MyException extends Exception { public MyException() {} public final String getTotalTrace() { final StringBuilder sb = new StringBuilder(); //:: error: (iterating.over.nullable) for (StackTraceElement st : getStackTrace()) { //:: error: (dereference.of.nullable) sb.append(st.toString()); sb.append("\n"); } return sb.toString(); } @SuppressWarnings("nullness") public StackTraceElement[] getStackTrace() { throw new RuntimeException("not implemented yet"); } }