Replace jakarta.activation with an internal MIME-type parser

Author: hyperxpro

client/src/main/java/org/asynchttpclient/request/body/multipart/FileLikePart.java

@@ -15,10 +15,6 @@
  */
 package org.asynchttpclient.request.body.multipart;
 
-import jakarta.activation.MimetypesFileTypeMap;
-
-import java.io.IOException;
-import java.io.InputStream;
 import java.nio.charset.Charset;
 
 import static org.asynchttpclient.util.MiscUtils.withDefault;
@@ -28,16 +24,6 @@
  */
 public abstract class FileLikePart extends PartBase {
 
-    private static final MimetypesFileTypeMap MIME_TYPES_FILE_TYPE_MAP;
-
-    static {
-        try (InputStream is = FileLikePart.class.getResourceAsStream("ahc-mime.types")) {
-            MIME_TYPES_FILE_TYPE_MAP = new MimetypesFileTypeMap(is);
-        } catch (IOException e) {
-            throw new ExceptionInInitializerError(e);
-        }
-    }
-
     /**
      * Default content encoding of file attachments.
      */
@@ -63,7 +49,7 @@ protected FileLikePart(String name, String contentType, Charset charset, String
     }
 
     private static String computeContentType(String contentType, String fileName) {
-        return contentType != null ? contentType : MIME_TYPES_FILE_TYPE_MAP.getContentType(withDefault(fileName, ""));
+        return contentType != null ? contentType : MimeTypes.getContentType(withDefault(fileName, ""));
     }
 
     public String getFileName() {

client/src/main/java/org/asynchttpclient/request/body/multipart/MimeTypes.java

@@ -0,0 +1,91 @@
+/*
+ *    Copyright (c) 2024-2026 AsyncHttpClient Project. All rights reserved.
+ *
+ *    Licensed under the Apache License, Version 2.0 (the "License");
+ *    you may not use this file except in compliance with the License.
+ *    You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *    Unless required by applicable law or agreed to in writing, software
+ *    distributed under the License is distributed on an "AS IS" BASIS,
+ *    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *    See the License for the specific language governing permissions and
+ *    limitations under the License.
+ */
+package org.asynchttpclient.request.body.multipart;
+
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.InputStreamReader;
+import java.nio.charset.StandardCharsets;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.Locale;
+import java.util.Map;
+
+/**
+ * Maps file extensions to content types using the bundled {@code ahc-mime.types} resource.
+ *
+ * <p>This is a self-contained replacement for {@code jakarta.activation.MimetypesFileTypeMap}, which was
+ * previously used solely to resolve the content type of {@link FileLikePart}s. The lookup mirrors the
+ * {@code MimetypesFileTypeMap} contract: the extension is the substring after the last {@code '.'}, and an
+ * unknown or missing extension resolves to {@value #DEFAULT_CONTENT_TYPE}. Unlike the original, the lookup is
+ * case-insensitive and relies exclusively on the bundled resource, so detection is deterministic across
+ * machines and classpaths.
+ */
+final class MimeTypes {
+
+    static final String DEFAULT_CONTENT_TYPE = "application/octet-stream";
+
+    /**
+     * Lower-cased file extension to content type. Built once at class load from {@code ahc-mime.types}.
+     */
+    private static final Map<String, String> EXTENSION_TO_CONTENT_TYPE;
+
+    static {
+        Map<String, String> map = new HashMap<>();
+        // The MimetypesFileTypeMap format: '#' comments, blank lines, and whitespace-delimited
+        // "type ext1 ext2 ..." entries. A later mapping for the same extension wins, matching the
+        // original Hashtable-based implementation.
+        try (InputStream is = MimeTypes.class.getResourceAsStream("ahc-mime.types");
+             BufferedReader reader = new BufferedReader(new InputStreamReader(is, StandardCharsets.ISO_8859_1))) {
+            String line;
+            while ((line = reader.readLine()) != null) {
+                line = line.trim();
+                if (line.isEmpty() || line.charAt(0) == '#') {
+                    continue;
+                }
+                String[] tokens = line.split("\\s+");
+                for (int i = 1; i < tokens.length; i++) {
+                    map.put(tokens[i].toLowerCase(Locale.ROOT), tokens[0]);
+                }
+            }
+        } catch (IOException e) {
+            throw new ExceptionInInitializerError(e);
+        }
+        EXTENSION_TO_CONTENT_TYPE = Collections.unmodifiableMap(map);
+    }
+
+    private MimeTypes() {
+    }
+
+    /**
+     * Resolves the content type for the given file name based on its extension.
+     *
+     * @param fileName the file name (may include a path; only the part after the last {@code '.'} is used)
+     * @return the mapped content type, or {@value #DEFAULT_CONTENT_TYPE} if the extension is absent or unknown
+     */
+    static String getContentType(String fileName) {
+        int dot = fileName.lastIndexOf('.');
+        if (dot < 0) {
+            return DEFAULT_CONTENT_TYPE;
+        }
+        String extension = fileName.substring(dot + 1);
+        if (extension.isEmpty()) {
+            return DEFAULT_CONTENT_TYPE;
+        }
+        return EXTENSION_TO_CONTENT_TYPE.getOrDefault(extension.toLowerCase(Locale.ROOT), DEFAULT_CONTENT_TYPE);
+    }
+}

client/src/test/java/org/asynchttpclient/request/body/multipart/MimeTypesTest.java

@@ -0,0 +1,53 @@
+/*
+ *    Copyright (c) 2024-2026 AsyncHttpClient Project. All rights reserved.
+ *
+ *    Licensed under the Apache License, Version 2.0 (the "License");
+ *    you may not use this file except in compliance with the License.
+ *    You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *    Unless required by applicable law or agreed to in writing, software
+ *    distributed under the License is distributed on an "AS IS" BASIS,
+ *    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *    See the License for the specific language governing permissions and
+ *    limitations under the License.
+ */
+package org.asynchttpclient.request.body.multipart;
+
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+class MimeTypesTest {
+
+    @Test
+    void resolvesKnownExtensions() {
+        assertEquals("image/png", MimeTypes.getContentType("image.png"));
+        assertEquals("text/html", MimeTypes.getContentType("data.html"));
+        assertEquals("image/jpeg", MimeTypes.getContentType("photo.jpeg"));
+    }
+
+    @Test
+    void lookupIsCaseInsensitive() {
+        assertEquals("image/png", MimeTypes.getContentType("IMAGE.PNG"));
+        assertEquals("text/html", MimeTypes.getContentType("Data.Html"));
+    }
+
+    @Test
+    void usesExtensionAfterLastDot() {
+        assertEquals("image/png", MimeTypes.getContentType("my.archive.png"));
+    }
+
+    @Test
+    void unknownExtensionFallsBackToDefault() {
+        assertEquals(MimeTypes.DEFAULT_CONTENT_TYPE, MimeTypes.getContentType("file.zzz"));
+    }
+
+    @Test
+    void missingExtensionFallsBackToDefault() {
+        assertEquals(MimeTypes.DEFAULT_CONTENT_TYPE, MimeTypes.getContentType("noextension"));
+        assertEquals(MimeTypes.DEFAULT_CONTENT_TYPE, MimeTypes.getContentType("trailingdot."));
+        assertEquals(MimeTypes.DEFAULT_CONTENT_TYPE, MimeTypes.getContentType(""));
+    }
+}

pom.xml

@@ -49,7 +49,6 @@
         <brotli4j.version>1.23.0</brotli4j.version>
         <slf4j.version>2.0.18</slf4j.version>
         <zstd-jni.version>1.5.7-8</zstd-jni.version>
-        <activation.version>2.0.1</activation.version>
         <logback.version>1.5.32</logback.version>
         <jetbrains-annotations.version>26.1.0</jetbrains-annotations.version>
         <testcontainers.version>2.0.5</testcontainers.version>
@@ -284,11 +283,6 @@
             <version>${slf4j.version}</version>
         </dependency>
 
-        <dependency>
-            <groupId>com.sun.activation</groupId>
-            <artifactId>jakarta.activation</artifactId>
-            <version>${activation.version}</version>
-        </dependency>
         <dependency>
             <groupId>org.jetbrains</groupId>
             <artifactId>annotations</artifactId>