@Data
@AllArgsConstructor
@NoArgsConstructor
public class Student {
private Integer age;
private String name;
}

List studentList = Lists.newArrayList();
studentList.add(new Student(28, "river"));
studentList.add(new Student(12, "lucy"));
studentList.add(new Student(33, "frank"));
studentList.add(new Student(33, "lucy"));

List studentDistinctList = studentList.stream()
.collect(Collectors.collectingAndThen
(Collectors.toCollection(() ->
new TreeSet<>(Comparator.comparing(t -> t.getName()))),
ArrayList::new
)
);
System.out.println(new Gson().toJson(studentDistinctList));

List studentDistinct2List = studentList.stream().filter(StreamUtil.distinctByKey(t->t.getName()))
.collect(Collectors.toList());
System.out.println(new Gson().toJson(studentDistinct2List));

public class StreamUtil {
/**
* https://stackoverflow.com/questions/23699371/java-8-distinct-by-property
* @param keyExtractor
* @param 
* @return
*/
public static  Predicate distinctByKey(Function<? super T, ?> keyExtractor) {
Set