sort filtered papers

src/main/java/ru/ulstu/paper/service/PaperService.java

@@ -47,15 +47,7 @@ public class PaperService {
     }
 
     public List<Paper> findAll() {
-        return paperRepository.findAll().stream().sorted((paper1, paper2) -> {
-            int statusCompareResult =
-                    Integer.valueOf(Arrays.asList(Paper.PaperStatus.values()).indexOf(paper1.getStatus()))
-                            .compareTo(Arrays.asList(Paper.PaperStatus.values()).indexOf(paper2.getStatus()));
-            if (statusCompareResult != 0) {
-                return statusCompareResult;
-            }
-            return paper1.getTitle().compareTo(paper2.getTitle());
-        }).collect(Collectors.toList());
+        return sortPapers(paperRepository.findAll());
     }
 
     public List<PaperDto> findAllDto() {
@@ -145,9 +137,21 @@ public class PaperService {
     }
 
     public List<PaperDto> filter(PaperFilterDto filterDto) {
-        return convert(paperRepository.filter(
+        return convert(sortPapers(paperRepository.filter(
                 filterDto.getFilterAuthorId() == null ? null : userService.findById(filterDto.getFilterAuthorId()),
-                filterDto.getYear()), PaperDto::new);
+                filterDto.getYear())), PaperDto::new);
+    }
+
+    private List<Paper> sortPapers(List<Paper> papers) {
+        return papers.stream().sorted((paper1, paper2) -> {
+            int statusCompareResult =
+                    Integer.valueOf(Arrays.asList(Paper.PaperStatus.values()).indexOf(paper1.getStatus()))
+                            .compareTo(Arrays.asList(Paper.PaperStatus.values()).indexOf(paper2.getStatus()));
+            if (statusCompareResult != 0) {
+                return statusCompareResult;
+            }
+            return paper1.getTitle().compareTo(paper2.getTitle());
+        }).collect(Collectors.toList());
     }
 
     public PaperDto findPaper(int id) {