// Issue 1147 https://github.com/typetools/checker-framework/issues/1147 // @below-java8-jdk-skip-test import java.util.StringJoiner; class Issue1147 { public static void main(String[] args) { StringJoiner sj = new StringJoiner(","); sj.add("a"); sj.add(null); System.out.println(sj); } }