#12 -- Improve performance

src/main/java/ru/ulstu/extractor/heuristic/api/StructuralUnitIdentifier.java

@@ -51,7 +51,10 @@ public abstract class StructuralUnitIdentifier {
                 .filter(file -> StringUtils.fileInSubdirectory(file.getPath(), projectPath, subDirectory))
                 .forEach(projectFile -> {
                     try {
-                        String detectedLanguage = getDetectorService().getDetectedLanguage(new String(Files.readAllBytes(projectFile.toPath())));
+                        String detectedLanguage = getDetectorService().getDetectedLanguage(
+                                projectFile.getName(),
+                                new String(Files.readAllBytes(projectFile.toPath())),
+                                DetectorService.LangDetectScrupulousness.LOW);
                         projectFileLanguageFrequency.put(detectedLanguage, projectFileLanguageFrequency.getOrDefault(detectedLanguage, 0) + 1);
                     } catch (IOException e) {
                         e.printStackTrace();

src/main/java/ru/ulstu/extractor/heuristic/service/DetectorService.java

@@ -1,3 +1,8 @@
+/*
+ * Copyright (C) 2021 Anton Romanov - All Rights Reserved
+ * You may use, distribute and modify this code, please write to: romanov73@gmail.com.
+ */
+
 package ru.ulstu.extractor.heuristic.service;
 
 import com.gargoylesoftware.htmlunit.WebClient;
@@ -9,11 +14,22 @@ import java.util.Arrays;
 import java.util.List;
 import java.util.Locale;
 
+import static ru.ulstu.extractor.heuristic.service.DetectorService.LangDetectScrupulousness.LOW;
+
 @Service
 public class DetectorService {
+    public enum LangDetectScrupulousness {LOW, HIGH}
+
     private final static String BASE_URL = "http://localhost:8080/lang-detector.html";
 
-    public String getDetectedLanguage(String code) {
+    public String getDetectedLanguage(String fileName, String code, LangDetectScrupulousness scrupulousness) {
+        if (scrupulousness == LOW) {
+            return DirectoryService.getFileExtension(fileName).orElse("");
+        }
+        return getDetectedLanguage(code);
+    }
+
+    private String getDetectedLanguage(String code) {
         String selectedLang = null;
         try (WebClient webClient = new WebClient()) {
             webClient.setJavaScriptTimeout(60 * 1000);

src/main/java/ru/ulstu/extractor/heuristic/service/DirectoryService.java

@@ -16,6 +16,7 @@ import java.util.Arrays;
 import java.util.Collections;
 import java.util.List;
 import java.util.Objects;
+import java.util.Optional;
 import java.util.stream.Collectors;
 
 /**
@@ -23,6 +24,7 @@ import java.util.stream.Collectors;
  */
 @Service
 public class DirectoryService {
+    private static final String FILE_EXTENSION_DELIMITER = ".";
 
     /**
      * Получить список файлов, рекурсивно обойдя все дерево каталогов проекта.
@@ -51,4 +53,11 @@ public class DirectoryService {
         }
         return Collections.emptyList();
     }
+
+    public static Optional<String> getFileExtension(String fileName) {
+        if (fileName == null || fileName.isEmpty() || fileName.lastIndexOf(FILE_EXTENSION_DELIMITER) < 0) {
+            return Optional.empty();
+        }
+        return Optional.of(fileName.substring(fileName.lastIndexOf(FILE_EXTENSION_DELIMITER) + 1));
+    }
 }