Java 8 Stream добавить в список
List<String> destList = Arrays.asList("foo");
List<String> newList = Arrays.asList("0", "1", "2", "3", "4", "5");
destList = Stream.concat(destList.stream(), newList.stream()).parallel()
.collect(Collectors.toList());
System.out.println(destList);
//output: [foo, 0, 1, 2, 3, 4, 5]
Thankful Trout