Added: Add annotations and modifiers

termux-shared/src/main/java/com/termux/shared/file/FileUtils.java

@@ -4,6 +4,7 @@ import android.os.Build;
 import android.system.Os;
 
 import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
 
 import com.google.common.io.RecursiveDeleteOption;
 import com.termux.shared.file.filesystem.FileType;
@@ -97,6 +98,7 @@ public class FileUtils {
      * @param path The {@code path} to convert.
      * @return Returns the {@code normalized path}.
      */
+    @Nullable
     public static String normalizePath(String path) {
         if (path == null) return null;
 
@@ -247,7 +249,7 @@ public class FileUtils {
     }
 
     /**
-     * Checks the type of file that exists at {@code filePath}.
+     * Get the type of file that exists at {@code filePath}.
      *
      * This function is a wrapper for
      * {@link FileTypes#getFileType(String, boolean)}
@@ -260,6 +262,7 @@ public class FileUtils {
      *                       returned.
      * @return Returns the {@link FileType} of file.
      */
+    @NonNull
     public static FileType getFileType(final String filePath, final boolean followLinks) {
         return FileTypes.getFileType(filePath, followLinks);
     }
@@ -1446,8 +1449,8 @@ public class FileUtils {
     }
 
     public static class ReadSerializableObjectResult {
-        public Error error;
-        public Serializable serializableObject;
+        public final Error error;
+        public final Serializable serializableObject;
 
         ReadSerializableObjectResult(Error error, Serializable serializableObject) {
             this.error = error;

termux-shared/src/main/java/com/termux/shared/file/FileUtilsErrno.java

@@ -94,7 +94,7 @@ public class FileUtilsErrno extends Errno {
 
 
     /** Defines the {@link Errno} mapping to get a shorter version of {@link FileUtilsErrno}. */
-    public static Map<Errno, Errno> ERRNO_SHORT_MAPPING = new HashMap<Errno, Errno>() {{
+    public static final Map<Errno, Errno> ERRNO_SHORT_MAPPING = new HashMap<Errno, Errno>() {{
         put(ERRNO_FILE_NOT_FOUND_AT_PATH, ERRNO_FILE_NOT_FOUND_AT_PATH_SHORT);
 
         put(ERRNO_NON_REGULAR_FILE_FOUND, ERRNO_NON_REGULAR_FILE_FOUND_SHORT);

termux-shared/src/main/java/com/termux/shared/file/filesystem/FileTypes.java

@@ -82,6 +82,7 @@ public class FileTypes {
      *                       returned.
      * @return Returns the {@link FileType} of file.
      */
+    @NonNull
     public static FileType getFileType(final String filePath, final boolean followLinks) {
         if (filePath == null || filePath.isEmpty()) return FileType.NO_EXIST;