Refactored ClassFinder to improve null handling, normalize class names, and support multiple resources; adjusted InjectionContext to use an effective class loader

Author: Michal-python

dependencyInjection/src/main/java/cat/michal/catbase/injector/ClassFinder.java

@@ -3,21 +3,25 @@
 import java.io.*;
 import java.net.JarURLConnection;
 import java.net.URL;
+import java.net.URISyntaxException;
 import java.util.*;
 import java.util.jar.JarEntry;
 import java.util.jar.JarFile;
 import java.util.stream.Collectors;
 
 public class ClassFinder {
     private final ClassLoader classLoader;
-    private final Collection<String> excludedEntries;
+    private final Set<String> excludedEntries;
 
-    ClassFinder(Collection<String> excludedEntries, ClassLoader classLoader) {
+    public ClassFinder(Collection<String> excludedEntries, ClassLoader classLoader) {
         this.classLoader = classLoader;
-        this.excludedEntries = excludedEntries;
+        this.excludedEntries = excludedEntries == null ? Collections.emptySet() : excludedEntries.stream()
+                .filter(Objects::nonNull)
+                .map(ClassFinder::normalizeName)
+                .collect(Collectors.toCollection(LinkedHashSet::new));
     }
 
-    ClassFinder() {
+    public ClassFinder() {
         this(Collections.emptyList(), ClassLoader.getSystemClassLoader());
     }
 
@@ -31,43 +35,52 @@ public List<Class<?>> findAllClasses(String packageName) {
 
     public List<String> findAllClassesPaths(String packageName) {
         String path = packageName.replace('.', '/');
-        URL resource = classLoader.getResource(path);
-        List<String> classes = new ArrayList<>();
-
-        if (resource == null) {
-            return classes;
-        }
+        Set<String> classes = new LinkedHashSet<>();
 
         try {
-            if ("jar".equals(resource.getProtocol())) {
-                JarURLConnection conn = (JarURLConnection) resource.openConnection();
-                try (JarFile jar = conn.getJarFile()) {
-                    Enumeration<JarEntry> entries = jar.entries();
-                    while (entries.hasMoreElements()) {
-                        JarEntry entry = entries.nextElement();
-                        if (entry.getName().startsWith(path + "/") && entry.getName().endsWith(".class")) {
-                            String className = entry.getName().replace('/', '.').replaceAll("\\.class$", "");
-                            classes.add(className);
+            Enumeration<URL> resources = classLoader.getResources(path);
+            while (resources.hasMoreElements()) {
+                URL resource = resources.nextElement();
+                String protocol = resource.getProtocol();
+                if ("jar".equals(protocol)) {
+                    JarURLConnection conn = (JarURLConnection) resource.openConnection();
+                    try (JarFile jar = conn.getJarFile()) {
+                        Enumeration<JarEntry> entries = jar.entries();
+                        while (entries.hasMoreElements()) {
+                            JarEntry entry = entries.nextElement();
+                            String name = entry.getName();
+                            if (name.startsWith(path + "/") && name.endsWith(".class") && !name.contains("$")) {
+                                String className = normalizeName(name);
+                                classes.add(className);
+                            }
                         }
                     }
+                } else if ("file".equals(protocol)) {
+                    File dir;
+                    try {
+                        dir = new File(resource.toURI());
+                    } catch (URISyntaxException e) {
+                        dir = new File(resource.getPath());
+                    }
+                    scanDirectory(packageName, dir, classes);
                 }
-            } else if ("file".equals(resource.getProtocol())) {
-                File dir = new File(resource.getFile());
-                scanDirectory(packageName, dir, classes);
             }
         } catch (IOException e) {
             e.printStackTrace();
         }
 
-        return classes;
+        classes.removeIf(excludedEntries::contains);
+        return new ArrayList<>(classes);
     }
 
-    private void scanDirectory(String packageName, File dir, List<String> classes) {
-        if (!dir.exists()) return;
-        for (File file : Objects.requireNonNull(dir.listFiles())) {
+    private void scanDirectory(String packageName, File dir, Collection<String> classes) {
+        if (dir == null || !dir.exists()) return;
+        File[] files = dir.listFiles();
+        if (files == null) return;
+        for (File file : files) {
             if (file.isDirectory()) {
                 scanDirectory(packageName + (packageName.isEmpty() ? "" : ".") + file.getName(), file, classes);
-            } else if (file.getName().endsWith(".class")) {
+            } else if (file.getName().endsWith(".class") && !file.getName().contains("$")) {
                 String className = packageName + (packageName.isEmpty() ? "" : ".") + file.getName().replaceAll("\\.class$", "");
                 classes.add(className);
             }
@@ -76,9 +89,18 @@ private void scanDirectory(String packageName, File dir, List<String> classes) {
 
     private Class<?> getClass(String className) {
         try {
-            return Class.forName(className.substring(0, className.lastIndexOf('.')));
-        } catch (ClassNotFoundException ignored) {
+            return classLoader.loadClass(className);
+        } catch (Throwable ignored) {
         }
         return null;
     }
+
+    private static String normalizeName(String name) {
+        if (name == null) return null;
+        String normalized = name.replace('/', '.');
+        if (normalized.endsWith(".class")) {
+            normalized = normalized.substring(0, normalized.length() - 6);
+        }
+        return normalized;
+    }
 }

dependencyInjection/src/main/java/cat/michal/catbase/injector/InjectionContext.java

@@ -14,7 +14,8 @@ public class InjectionContext {
     public InjectionContext(Collection<String> packagePaths, Collection<String> excludedEntries, ClassLoader classLoader) {
         this.classes = new ArrayList<>();
         this.dependencies = new ArrayList<>();
-        ClassFinder classFinder = classLoader == null ? new ClassFinder() : new ClassFinder(excludedEntries, classLoader);
+        ClassLoader effectiveClassLoader = classLoader != null ? classLoader : Thread.currentThread().getContextClassLoader();
+        ClassFinder classFinder = new ClassFinder(excludedEntries, effectiveClassLoader);
 
         packagePaths.forEach(packagePath -> this.classes.addAll(classFinder.findAllClasses(packagePath)));
     }