FileSortOrder*: convert to Kotlin

Need more kotlin in the codebase and these were simple enough

Signed-off-by: Álvaro Brey Vilas <alvaro.brey@nextcloud.com>

scripts/analysis/lint-results.txt

@@ -1,2 +1,2 @@
 DO NOT TOUCH; GENERATED BY DRONE
-      <span class="mdl-layout-title">Lint Report: 102 warnings</span>
+      <span class="mdl-layout-title">Lint Report: 103 warnings</span>

src/main/java/com/owncloud/android/utils/FileSortOrder.java

@@ -1,107 +0,0 @@
-/*
- * Nextcloud Android client application
- *
- * @author Sven R. Kunze
- * Copyright (C) 2017 Sven R. Kunze
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU AFFERO GENERAL PUBLIC LICENSE
- * License as published by the Free Software Foundation; either
- * version 3 of the License, or any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU AFFERO GENERAL PUBLIC LICENSE for more details.
- *
- * You should have received a copy of the GNU Affero General Public
- * License along with this program.  If not, see <http://www.gnu.org/licenses/>.
- */
-
-package com.owncloud.android.utils;
-
-import com.owncloud.android.datamodel.OCFile;
-import com.owncloud.android.lib.resources.trashbin.model.TrashbinFile;
-
-import java.io.File;
-import java.util.Collections;
-import java.util.HashMap;
-import java.util.List;
-import java.util.Map;
-
-/**
- * Sort order
- */
-
-public class FileSortOrder {
-    public static final String sort_a_to_z_id = "sort_a_to_z";
-    public static final String sort_z_to_a_id = "sort_z_to_a";
-    public static final String sort_old_to_new_id = "sort_old_to_new";
-    public static final String sort_new_to_old_id = "sort_new_to_old";
-    public static final String sort_small_to_big_id = "sort_small_to_big";
-    public static final String sort_big_to_small_id = "sort_big_to_small";
-
-    public static final FileSortOrder sort_a_to_z = new FileSortOrderByName(sort_a_to_z_id, true);
-    public static final FileSortOrder sort_z_to_a = new FileSortOrderByName(sort_z_to_a_id, false);
-    public static final FileSortOrder sort_old_to_new = new FileSortOrderByDate(sort_old_to_new_id, true);
-    public static final FileSortOrder sort_new_to_old = new FileSortOrderByDate(sort_new_to_old_id, false);
-    public static final FileSortOrder sort_small_to_big = new FileSortOrderBySize(sort_small_to_big_id, true);
-    public static final FileSortOrder sort_big_to_small = new FileSortOrderBySize(sort_big_to_small_id, false);
-
-    public static final Map<String, FileSortOrder> sortOrders;
-
-    public enum Type {
-        trashBinView, localFileListView
-    }
-    static {
-        HashMap<String, FileSortOrder> temp = new HashMap<>();
-        temp.put(sort_a_to_z.name, sort_a_to_z);
-        temp.put(sort_z_to_a.name, sort_z_to_a);
-        temp.put(sort_old_to_new.name, sort_old_to_new);
-        temp.put(sort_new_to_old.name, sort_new_to_old);
-        temp.put(sort_small_to_big.name, sort_small_to_big);
-        temp.put(sort_big_to_small.name, sort_big_to_small);
-
-        sortOrders = Collections.unmodifiableMap(temp);
-    }
-
-    public String name;
-    public boolean isAscending;
-
-    public FileSortOrder(String name, boolean ascending) {
-        this.name = name;
-        isAscending = ascending;
-    }
-
-    public List<OCFile> sortCloudFiles(List<OCFile> files) {
-        return sortCloudFilesByFavourite(files);
-    }
-
-    public List<File> sortLocalFiles(List<File> files) {
-        return files;
-    }
-
-    public List<TrashbinFile> sortTrashbinFiles(List<TrashbinFile> files) {
-        return files;
-    }
-
-    /**
-     * Sorts list by Favourites.
-     *
-     * @param files files to sort
-     */
-    public static List<OCFile> sortCloudFilesByFavourite(List<OCFile> files) {
-        Collections.sort(files, (o1, o2) -> {
-            if (o1.isFavorite() && o2.isFavorite()) {
-                return 0;
-            } else if (o1.isFavorite()) {
-                return -1;
-            } else if (o2.isFavorite()) {
-                return 1;
-            }
-            return 0;
-        });
-
-        return files;
-    }
-}

src/main/java/com/owncloud/android/utils/FileSortOrder.kt

@@ -0,0 +1,109 @@
+/*
+ * Nextcloud Android client application
+ *
+ * @author Sven R. Kunze
+ * Copyright (C) 2017 Sven R. Kunze
+ * Copyright (C) 2022 Álvaro Brey Vilas
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU AFFERO GENERAL PUBLIC LICENSE
+ * License as published by the Free Software Foundation; either
+ * version 3 of the License, or any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU AFFERO GENERAL PUBLIC LICENSE for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public
+ * License along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+package com.owncloud.android.utils
+
+import com.owncloud.android.datamodel.OCFile
+import com.owncloud.android.lib.resources.trashbin.model.TrashbinFile
+import java.io.File
+import java.util.Collections
+
+/**
+ * Sort order
+ */
+open class FileSortOrder(@JvmField var name: String, var isAscending: Boolean) {
+
+    val sortMultiplier: Int
+        get() = if (isAscending) 1 else -1
+
+    @Suppress("EnumNaming") // already saved in user preferences -.-'
+    enum class Type {
+        trashBinView, localFileListView
+    }
+
+    companion object {
+        const val sort_a_to_z_id = "sort_a_to_z"
+        const val sort_z_to_a_id = "sort_z_to_a"
+        const val sort_old_to_new_id = "sort_old_to_new"
+        const val sort_new_to_old_id = "sort_new_to_old"
+        const val sort_small_to_big_id = "sort_small_to_big"
+        const val sort_big_to_small_id = "sort_big_to_small"
+
+        @JvmField
+        val sort_a_to_z: FileSortOrder = FileSortOrderByName(sort_a_to_z_id, true)
+
+        @JvmField
+        val sort_z_to_a: FileSortOrder = FileSortOrderByName(sort_z_to_a_id, false)
+
+        @JvmField
+        val sort_old_to_new: FileSortOrder = FileSortOrderByDate(sort_old_to_new_id, true)
+
+        @JvmField
+        val sort_new_to_old: FileSortOrder = FileSortOrderByDate(sort_new_to_old_id, false)
+
+        @JvmField
+        val sort_small_to_big: FileSortOrder = FileSortOrderBySize(sort_small_to_big_id, true)
+
+        @JvmField
+        val sort_big_to_small: FileSortOrder = FileSortOrderBySize(sort_big_to_small_id, false)
+
+        @JvmField
+        val sortOrders: Map<String, FileSortOrder> = Collections.unmodifiableMap(
+            mapOf(
+                sort_a_to_z.name to sort_a_to_z,
+                sort_z_to_a.name to sort_z_to_a,
+                sort_old_to_new.name to sort_old_to_new,
+                sort_new_to_old.name to sort_new_to_old,
+                sort_small_to_big.name to sort_small_to_big,
+                sort_big_to_small.name to sort_big_to_small
+            )
+        )
+
+        /**
+         * Sorts list by Favourites.
+         *
+         * @param files files to sort
+         */
+        @JvmStatic
+        fun sortCloudFilesByFavourite(files: MutableList<OCFile>): List<OCFile> {
+            files.sortWith { o1: OCFile, o2: OCFile ->
+                when {
+                    o1.isFavorite && o2.isFavorite -> 0
+                    o1.isFavorite -> -1
+                    o2.isFavorite -> 1
+                    else -> 0
+                }
+            }
+            return files
+        }
+    }
+
+    open fun sortCloudFiles(files: MutableList<OCFile>): List<OCFile> {
+        return sortCloudFilesByFavourite(files)
+    }
+
+    open fun sortLocalFiles(files: MutableList<File>): List<File> {
+        return files
+    }
+
+    open fun sortTrashbinFiles(files: MutableList<TrashbinFile>): List<TrashbinFile> {
+        return files
+    }
+}

src/main/java/com/owncloud/android/utils/FileSortOrderByDate.java

@@ -1,82 +0,0 @@
-/*
- * Nextcloud Android client application
- *
- * @author Sven R. Kunze
- * Copyright (C) 2017 Sven R. Kunze
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU AFFERO GENERAL PUBLIC LICENSE
- * License as published by the Free Software Foundation; either
- * version 3 of the License, or any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU AFFERO GENERAL PUBLIC LICENSE for more details.
- *
- * You should have received a copy of the GNU Affero General Public
- * License along with this program.  If not, see <http://www.gnu.org/licenses/>.
- */
-
-package com.owncloud.android.utils;
-
-import com.owncloud.android.datamodel.OCFile;
-import com.owncloud.android.lib.resources.trashbin.model.TrashbinFile;
-
-import java.io.File;
-import java.util.Collections;
-import java.util.List;
-
-/**
- * Created by srkunze on 28.08.17.
- */
-public class FileSortOrderByDate extends FileSortOrder {
-
-    FileSortOrderByDate(String name, boolean ascending) {
-        super(name, ascending);
-    }
-
-    /**
-     * Sorts list by Date.
-     *
-     * @param files list of files to sort
-     */
-    public List<OCFile> sortCloudFiles(List<OCFile> files) {
-        final int multiplier = isAscending ? 1 : -1;
-
-        Collections.sort(files, (o1, o2) ->
-                multiplier * Long.compare(o1.getModificationTimestamp(), o2.getModificationTimestamp()));
-
-        return super.sortCloudFiles(files);
-    }
-
-    /**
-     * Sorts list by Date.
-     *
-     * @param files list of files to sort
-     */
-    @Override
-    public List<TrashbinFile> sortTrashbinFiles(List<TrashbinFile> files) {
-        final int multiplier = isAscending ? 1 : -1;
-
-        Collections.sort(files, (o1, o2) -> {
-            return multiplier * Long.compare(o1.getDeletionTimestamp(),o2.getDeletionTimestamp());
-        });
-
-        return super.sortTrashbinFiles(files);
-    }
-
-    /**
-     * Sorts list by Date.
-     *
-     * @param files list of files to sort
-     */
-    @Override
-    public List<File> sortLocalFiles(List<File> files) {
-        final int multiplier = isAscending ? 1 : -1;
-
-        Collections.sort(files, (o1, o2) -> multiplier * Long.compare(o1.lastModified(),o2.lastModified()));
-
-        return files;
-    }
-}

src/main/java/com/owncloud/android/utils/FileSortOrderByDate.kt

@@ -0,0 +1,69 @@
+/*
+ * Nextcloud Android client application
+ *
+ * @author Sven R. Kunze
+ * Copyright (C) 2017 Sven R. Kunze
+ * Copyright (C) 2022 Álvaro Brey Vilas
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU AFFERO GENERAL PUBLIC LICENSE
+ * License as published by the Free Software Foundation; either
+ * version 3 of the License, or any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU AFFERO GENERAL PUBLIC LICENSE for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public
+ * License along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+package com.owncloud.android.utils
+
+import com.owncloud.android.datamodel.OCFile
+import com.owncloud.android.lib.resources.trashbin.model.TrashbinFile
+import java.io.File
+
+/**
+ * Created by srkunze on 28.08.17.
+ */
+class FileSortOrderByDate(name: String, ascending: Boolean) : FileSortOrder(name, ascending) {
+    /**
+     * Sorts list by Date.
+     *
+     * @param files list of files to sort
+     */
+    override fun sortCloudFiles(files: MutableList<OCFile>): List<OCFile> {
+        val multiplier = if (isAscending) 1 else -1
+        files.sortWith { o1: OCFile, o2: OCFile ->
+            multiplier * o1.modificationTimestamp.compareTo(o2.modificationTimestamp)
+        }
+        return super.sortCloudFiles(files)
+    }
+
+    /**
+     * Sorts list by Date.
+     *
+     * @param files list of files to sort
+     */
+    override fun sortTrashbinFiles(files: MutableList<TrashbinFile>): List<TrashbinFile> {
+        val multiplier = if (isAscending) 1 else -1
+        files.sortWith { o1: TrashbinFile, o2: TrashbinFile ->
+            multiplier * o1.deletionTimestamp.compareTo(o2.deletionTimestamp)
+        }
+        return super.sortTrashbinFiles(files)
+    }
+
+    /**
+     * Sorts list by Date.
+     *
+     * @param files list of files to sort
+     */
+    override fun sortLocalFiles(files: MutableList<File>): List<File> {
+        val multiplier = if (isAscending) 1 else -1
+        files.sortWith { o1: File, o2: File ->
+            multiplier * o1.lastModified().compareTo(o2.lastModified())
+        }
+        return files
+    }
+}

src/main/java/com/owncloud/android/utils/FileSortOrderByName.java

@@ -1,115 +0,0 @@
-/*
- * Nextcloud Android client application
- *
- * @author Sven R. Kunze
- * Copyright (C) 2017 Sven R. Kunze
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU AFFERO GENERAL PUBLIC LICENSE
- * License as published by the Free Software Foundation; either
- * version 3 of the License, or any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU AFFERO GENERAL PUBLIC LICENSE for more details.
- *
- * You should have received a copy of the GNU Affero General Public
- * License along with this program.  If not, see <http://www.gnu.org/licenses/>.
- */
-
-package com.owncloud.android.utils;
-
-import com.owncloud.android.datamodel.OCFile;
-import com.owncloud.android.lib.resources.trashbin.model.TrashbinFile;
-
-import java.io.File;
-import java.util.Collections;
-import java.util.List;
-import java.util.Locale;
-
-import edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
-import third_parties.daveKoeller.AlphanumComparator;
-
-/**
- * Created by srkunze on 28.08.17.
- */
-public class FileSortOrderByName extends FileSortOrder {
-
-    FileSortOrderByName(String name, boolean ascending) {
-        super(name, ascending);
-    }
-
-    /**
-     * Sorts list by Name.
-     *
-     * @param files files to sort
-     */
-    @SuppressFBWarnings("Bx")
-    public List<OCFile> sortCloudFiles(List<OCFile> files) {
-        final int multiplier = isAscending ? 1 : -1;
-
-        Collections.sort(files, (o1, o2) -> {
-            if (o1.isFolder() && o2.isFolder()) {
-                return multiplier * AlphanumComparator.compare(o1, o2);
-            } else if (o1.isFolder()) {
-                return -1;
-            } else if (o2.isFolder()) {
-                return 1;
-            }
-            return multiplier * AlphanumComparator.compare(o1, o2);
-        });
-
-        return super.sortCloudFiles(files);
-    }
-
-    /**
-     * Sorts list by Name.
-     *
-     * @param files files to sort
-     */
-    @SuppressFBWarnings("Bx")
-    @Override
-    public List<TrashbinFile> sortTrashbinFiles(List<TrashbinFile> files) {
-        final int multiplier = isAscending ? 1 : -1;
-
-        Collections.sort(files, (o1, o2) -> {
-            if (o1.isFolder() && o2.isFolder()) {
-                return multiplier * AlphanumComparator.compare(o1, o2);
-            } else if (o1.isFolder()) {
-                return -1;
-            } else if (o2.isFolder()) {
-                return 1;
-            }
-            return multiplier * AlphanumComparator.compare(o1, o2);
-        });
-
-        return super.sortTrashbinFiles(files);
-    }
-
-    /**
-     * Sorts list by Name.
-     *
-     * @param files files to sort
-     */
-    @Override
-    public List<File> sortLocalFiles(List<File> files) {
-        final int multiplier = isAscending ? 1 : -1;
-
-        Collections.sort(files, (o1, o2) -> {
-            if (o1.isDirectory() && o2.isDirectory()) {
-                return multiplier * o1.getPath().toLowerCase(Locale.getDefault())
-                        .compareTo(o2.getPath().toLowerCase(Locale.getDefault()));
-            } else if (o1.isDirectory()) {
-                return -1;
-            } else if (o2.isDirectory()) {
-                return 1;
-            }
-            return multiplier * AlphanumComparator.compare(o1.getPath()
-                            .toLowerCase(Locale.getDefault()),
-                                                           o2.getPath().toLowerCase(Locale.getDefault()));
-        });
-
-        return files;
-    }
-}

src/main/java/com/owncloud/android/utils/FileSortOrderByName.kt

@@ -0,0 +1,89 @@
+/*
+ * Nextcloud Android client application
+ *
+ * @author Sven R. Kunze
+ * Copyright (C) 2017 Sven R. Kunze
+ * Copyright (C) 2022 Álvaro Brey Vilas
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU AFFERO GENERAL PUBLIC LICENSE
+ * License as published by the Free Software Foundation; either
+ * version 3 of the License, or any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU AFFERO GENERAL PUBLIC LICENSE for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public
+ * License along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+package com.owncloud.android.utils
+
+import com.owncloud.android.datamodel.OCFile
+import com.owncloud.android.lib.resources.files.model.ServerFileInterface
+import com.owncloud.android.lib.resources.trashbin.model.TrashbinFile
+import edu.umd.cs.findbugs.annotations.SuppressFBWarnings
+import third_parties.daveKoeller.AlphanumComparator
+import java.io.File
+import java.util.Locale
+
+/**
+ * Sorts list by Name.
+ *
+ * Created by srkunze on 28.08.17.
+ */
+class FileSortOrderByName internal constructor(name: String?, ascending: Boolean) : FileSortOrder(name!!, ascending) {
+    /**
+     *
+     * @param files files to sort
+     */
+    @SuppressFBWarnings("Bx")
+    override fun sortCloudFiles(files: MutableList<OCFile>): List<OCFile> {
+        val sortedByName = sortServerFiles(files)
+        return super.sortCloudFiles(sortedByName)
+    }
+
+    /**
+     * Sorts list by Name.
+     *
+     * @param files files to sort
+     */
+    override fun sortTrashbinFiles(files: MutableList<TrashbinFile>): List<TrashbinFile> {
+        val sortedByName = sortServerFiles(files)
+        return super.sortTrashbinFiles(sortedByName)
+    }
+
+    private fun <T : ServerFileInterface> sortServerFiles(files: MutableList<T>): MutableList<T> {
+        files.sortWith { o1: ServerFileInterface, o2: ServerFileInterface ->
+            when {
+                o1.isFolder && o2.isFolder -> sortMultiplier * AlphanumComparator.compare(o1, o2)
+                o1.isFolder -> -1
+                o2.isFolder -> 1
+                else -> sortMultiplier * AlphanumComparator.compare(o1, o2)
+            }
+        }
+        return files
+    }
+
+    /**
+     * Sorts list by Name.
+     *
+     * @param files files to sort
+     */
+    override fun sortLocalFiles(files: MutableList<File>): List<File> {
+        files.sortWith { o1: File, o2: File ->
+            when {
+                o1.isDirectory && o2.isDirectory -> sortMultiplier * o1.path.lowercase(Locale.getDefault())
+                    .compareTo(o2.path.lowercase(Locale.getDefault()))
+                o1.isDirectory -> -1
+                o2.isDirectory -> 1
+                else -> sortMultiplier * AlphanumComparator.compare(
+                    o1.path.lowercase(Locale.getDefault()),
+                    o2.path.lowercase(Locale.getDefault())
+                )
+            }
+        }
+        return files
+    }
+}

src/main/java/com/owncloud/android/utils/FileSortOrderBySize.java

@@ -1,112 +0,0 @@
-/*
- * Nextcloud Android client application
- *
- * @author Sven R. Kunze
- * Copyright (C) 2017 Sven R. Kunze
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU AFFERO GENERAL PUBLIC LICENSE
- * License as published by the Free Software Foundation; either
- * version 3 of the License, or any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU AFFERO GENERAL PUBLIC LICENSE for more details.
- *
- * You should have received a copy of the GNU Affero General Public
- * License along with this program.  If not, see <http://www.gnu.org/licenses/>.
- */
-
-package com.owncloud.android.utils;
-
-import com.owncloud.android.datamodel.OCFile;
-import com.owncloud.android.lib.resources.trashbin.model.TrashbinFile;
-
-import java.io.File;
-import java.util.Collections;
-import java.util.List;
-
-
-/**
- * Sorts files by sizes
- */
-public class FileSortOrderBySize extends FileSortOrder {
-
-    FileSortOrderBySize(String name, boolean ascending) {
-        super(name, ascending);
-    }
-
-    /**
-     * Sorts list by Size.
-     *
-     * @param files list of files to sort
-     */
-    public List<OCFile> sortCloudFiles(List<OCFile> files) {
-        final int multiplier = isAscending ? 1 : -1;
-
-        Collections.sort(files, (o1, o2) -> {
-            if (o1.isFolder() && o2.isFolder()) {
-                return multiplier * Long.compare(o1.getFileLength(), o2.getFileLength());
-            } else if (o1.isFolder()) {
-                return -1;
-            } else if (o2.isFolder()) {
-                return 1;
-            } else {
-                return multiplier * Long.compare(o1.getFileLength(),o2.getFileLength());
-            }
-        });
-
-        return super.sortCloudFiles(files);
-    }
-
-    /**
-     * Sorts list by Size.
-     *
-     * @param files list of files to sort
-     */
-    @Override
-    public List<TrashbinFile> sortTrashbinFiles(List<TrashbinFile> files) {
-        final int multiplier = isAscending ? 1 : -1;
-
-        Collections.sort(files, (o1, o2) -> {
-            if (o1.isFolder() && o2.isFolder()) {
-                return multiplier * Long.compare(o1.getFileLength(), o2.getFileLength());
-            } else if (o1.isFolder()) {
-                return -1;
-
-            } else if (o2.isFolder()) {
-                return 1;
-            } else {
-                return multiplier * Long.compare(o1.getFileLength(),o2.getFileLength());
-            }
-        });
-
-        return super.sortTrashbinFiles(files);
-    }
-
-    /**
-     * Sorts list by Size.
-     *
-     * @param files list of files to sort
-     */
-    @Override
-    public List<File> sortLocalFiles(List<File> files) {
-        final int multiplier = isAscending ? 1 : -1;
-
-        Collections.sort(files, (o1, o2) -> {
-            if (o1.isDirectory() && o2.isDirectory()) {
-                return multiplier * Long.compare(FileStorageUtils.getFolderSize(o1),
-                                                 FileStorageUtils.getFolderSize(o2));
-            } else if (o1.isDirectory()) {
-                return -1;
-            } else if (o2.isDirectory()) {
-                return 1;
-            } else {
-                return multiplier * Long.compare(o1.length(),o2.length());
-            }
-        });
-
-        return files;
-    }
-}

src/main/java/com/owncloud/android/utils/FileSortOrderBySize.kt

@@ -0,0 +1,68 @@
+/*
+ * Nextcloud Android client application
+ *
+ * @author Sven R. Kunze
+ * Copyright (C) 2017 Sven R. Kunze
+ * Copyright (C) 2022 Álvaro Brey Vilas
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU AFFERO GENERAL PUBLIC LICENSE
+ * License as published by the Free Software Foundation; either
+ * version 3 of the License, or any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU AFFERO GENERAL PUBLIC LICENSE for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public
+ * License along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+package com.owncloud.android.utils
+
+import com.owncloud.android.datamodel.OCFile
+import com.owncloud.android.lib.resources.files.model.ServerFileInterface
+import com.owncloud.android.lib.resources.trashbin.model.TrashbinFile
+import java.io.File
+
+/**
+ * Sorts files by sizes
+ */
+class FileSortOrderBySize internal constructor(name: String?, ascending: Boolean) : FileSortOrder(name!!, ascending) {
+
+    override fun sortCloudFiles(files: MutableList<OCFile>): List<OCFile> {
+        val sortedBySize = sortServerFiles(files)
+        return super.sortCloudFiles(sortedBySize)
+    }
+
+    override fun sortTrashbinFiles(files: MutableList<TrashbinFile>): List<TrashbinFile> {
+        val sortedBySize = sortServerFiles(files)
+        return super.sortTrashbinFiles(sortedBySize)
+    }
+
+    private fun <T : ServerFileInterface> sortServerFiles(files: MutableList<T>): MutableList<T> {
+        files.sortWith { o1: ServerFileInterface, o2: ServerFileInterface ->
+            when {
+                o1.isFolder && o2.isFolder -> sortMultiplier * o1.fileLength.compareTo(o2.fileLength)
+                o1.isFolder -> -1
+                o2.isFolder -> 1
+                else -> sortMultiplier * o1.fileLength.compareTo(o2.fileLength)
+            }
+        }
+        return files
+    }
+
+    override fun sortLocalFiles(files: MutableList<File>): List<File> {
+
+        files.sortWith { o1: File, o2: File ->
+            when {
+                o1.isDirectory && o2.isDirectory -> sortMultiplier * FileStorageUtils.getFolderSize(o1)
+                    .compareTo(FileStorageUtils.getFolderSize(o2))
+                o1.isDirectory -> -1
+                o2.isDirectory -> 1
+                else -> sortMultiplier * o1.length().compareTo(o2.length())
+            }
+        }
+        return files
+    }
+}