Added Document subclasses

Lab3/src/main/java/org/lumijiez/enums/FileType.java

@@ -4,8 +4,22 @@ import java.util.ArrayList;
 import java.util.List;
 
 public enum FileType {
-    IMAGE, PLAINTEXT, FILE, CODE;
+    IMAGE("Image"), PLAINTEXT("Plaintext"), FILE("File"), CODE("Code"), NONE("None");
     public List<String> typeExtensions;
+    public final String typeName;
+
+    FileType(String typeName) {
+        this.typeName = typeName;
+    }
+
+    public static FileType getFileType(String extension) {
+        for (FileType fileType : values()) {
+            if (fileType.typeExtensions.contains(extension.toLowerCase())) {
+                return fileType;
+            }
+        }
+        return NONE;
+    }
 
     static {
         IMAGE.typeExtensions = new ArrayList<>(List.of("jpg", "png"));