add sorter

src/main/java/org/embulk/input/filename/FilenameInputPlugin.java

@@ -162,45 +162,32 @@ public class FilenameInputPlugin
             
             // We have to sort the files before we set them to the tasks.
             // Here we get the parameter about the order
+            
+            Comparator comparator;
             String order = task.getLoadOrder();
-            if (order.equals("")){order = "ALPHABETICAL";}
+            switch (order) {
+                case "ASCEND_MODIFIED": comparator = AscendModifiedSorter.getComparator();
+                break;
+                case "DESCEND_MODIFIED": comparator = DescendModifiedSorter.getComparator();
+                break;
+                case "ASCEND_CREATION": comparator = AscendCreationSorter.getComparator();
+                break;
+                case "DESCEND_CREATION": comparator = DescendModifiedSorter.getComparator();
+                break;
+                default: comparator = new Comparator<String>();
+                break;
+            }
+            
+            
             
             // This method return the files in a directory,however the files in the varibale files is in random order. we have to sort them next
             ArrayList<String> files = listFiles(task,Paths.get(dir).normalize(),lastPath,order);
             
-            // Sort the files if each directory
-            if (order.equals("ALPHABETICAL")){
-                Collections.sort(files);
-            } else if(order.equals("ASCEND_MODIFIED") || order.equals("DESCEND_MODIFIED")){
-                Collections.sort(files,new Comparator<String>(){
-                    @Override
-                    public int compare(String f1, String f2) {
-                        try{
-                            return getLastModifiedTime(f1).compareTo(getLastModifiedTime(f2));
-                        } catch (IOException ex){
-                            ex.printStackTrace();
-                        }
-                        return 0;
-                    }
-                });
-                if (order.equals("DESCEND_MODIFIED")){ Collections.reverse(files); }
-            } else if ( order.equals("ASCEND_CREATION") || order.equals("DESCEND_CREATION") ){
-                Collections.sort(files,new Comparator<String>(){
-                    @Override
-                    public int compare(String f1, String f2) {
-                        try{
-                            return getCreationTime(f1).compareTo(getCreationTime(f2));
-                        } catch (IOException ex){
-                            ex.printStackTrace();
-                        }
-                        return 0;
-                    }
-                });
-          
-                if ( order.equals("DESCEND_CREATION") ) { Collections.reverse(files);}
-            } else {
-                throw new RuntimeException("Input a correct order");
-            }
+            
+            
+            // Sort the files for each directory
+            Collections.sort(files,comparator);
+        
             
             // End of sort
             
@@ -398,3 +385,76 @@ public class FilenameInputPlugin
       return fileTime;
     }
 }
+
+interface Sorter {
+    public static Comparator getComparator();
+}
+
+class AscendModifiedSorter implements Sorter {
+    public static Comparator getComparator(){
+        return new Comparator<String>(){
+                    @Override
+                    public int compare(String f1, String f2) {
+                        try{
+                            return getLastModifiedTime(f1).compareTo(getLastModifiedTime(f2));
+                        } catch (IOException ex){
+                            ex.printStackTrace();
+                        }
+                        return 0;
+                    }
+                });
+    }
+}
+
+
+
+
+class AscendCreationSorter implements Sorter {
+    public static Comparator getComparator(){
+        return new Comparator<String>(){
+                    @Override
+                    public int compare(String f1, String f2) {
+                        try{
+                            return getCreationTime(f1).compareTo(getCreationTime(f2));
+                        } catch (IOException ex){
+                            ex.printStackTrace();
+                        }
+                        return 0;
+                    }
+                });
+    }
+}
+
+class DescendModifiedSorter implements Sorter {
+    public static Comparator getComparator(){
+        return new Comparator<String>(){
+                    @Override
+                    public int compare(String f1, String f2) {
+                        try{
+                            return - getLastModifiedTime(f1).compareTo(getLastModifiedTime(f2));
+                        } catch (IOException ex){
+                            ex.printStackTrace();
+                        }
+                        return 0;
+                    }
+                });
+    }
+}
+
+
+
+class DescendCreationSorter implements Sorter {
+    public static Comparator getComparator(){
+        return new Comparator<String>(){
+                    @Override
+                    public int compare(String f1, String f2) {
+                        try{
+                            return - getCreationTime(f1).compareTo(getCreationTime(f2));
+                        } catch (IOException ex){
+                            ex.printStackTrace();
+                        }
+                        return 0;
+                    }
+                });
+    }
+}
\ No newline at end of file