create new list in sort method to avoid side effects

effective-webwork · Oct 30, 2023 · 8d51e53 · 8d51e53
1 parent c2213a6
commit 8d51e53
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diff --git a/Kitodo/src/main/java/org/kitodo/production/services/data/ImportService.java b/Kitodo/src/main/java/org/kitodo/production/services/data/ImportService.java
@@ -983,15 +983,16 @@ private Process loadParentProcess(Ruleset ruleset, int projectId, String parentI
      * @param projectId projectId by which the list gets sorted
      */
     public List<ProcessDTO> sortProcessesByProjectID(List<ProcessDTO> processDTOs, int projectId) {
+        List<ProcessDTO> sortedList = new ArrayList<>(processDTOs);
         Comparator<ProcessDTO> comparator = Comparator.comparingInt(obj -> {
             if (obj.getProject().getId() == projectId) {
                 return 0; // Matching value should come first
             } else {
                 return 1; // Non-matching value comes later
             }
         });
-        Collections.sort(processDTOs, comparator);
-        return processDTOs;
+        Collections.sort(sortedList, comparator);
+        return sortedList;
     }
 
     /**

diff --git a/Kitodo/src/test/java/org/kitodo/production/services/data/ImportServiceTest.java b/Kitodo/src/test/java/org/kitodo/production/services/data/ImportServiceTest.java
@@ -47,9 +47,9 @@ public void shouldSortProcessesWithProvidedProjectIdFirst()  {
         List<ProcessDTO> processes = new ArrayList<>(Arrays.asList(processOne, processTwo, processThree));
 
         ImportService importService = new ImportService();
-        importService.sortProcessesByProjectID(processes, 9);
+        List<ProcessDTO> sortedProcesses = importService.sortProcessesByProjectID(processes, 9);
 
-        int projectIdOfFirstProcess = processes.get(0).getProject().getId();
+        int projectIdOfFirstProcess = sortedProcesses.get(0).getProject().getId();
 
         Assert.assertEquals("Process not sorted based on provided projectId",9,
                 projectIdOfFirstProcess);