diff --git a/web/src/main/kotlin/cn/tursom/web/HttpContent.kt b/web/src/main/kotlin/cn/tursom/web/HttpContent.kt
index 7d7d60a..c1c02ac 100644
--- a/web/src/main/kotlin/cn/tursom/web/HttpContent.kt
+++ b/web/src/main/kotlin/cn/tursom/web/HttpContent.kt
@@ -119,8 +119,6 @@ interface HttpContent : ResponseHeaderAdapter, RequestHeaderAdapter {
     chunkSize: Int = 8192
   )
 
-  fun setContextType(type: Any) = setResponseHeader("Content-Type", type)
-
   fun jump(url: String) = temporaryMoved(url)
   fun moved(url: String) = permanentlyMoved(url)
 
diff --git a/web/src/main/kotlin/cn/tursom/web/ResponseHeaderAdapter.kt b/web/src/main/kotlin/cn/tursom/web/ResponseHeaderAdapter.kt
index f22b68b..250f7ac 100644
--- a/web/src/main/kotlin/cn/tursom/web/ResponseHeaderAdapter.kt
+++ b/web/src/main/kotlin/cn/tursom/web/ResponseHeaderAdapter.kt
@@ -1,6 +1,7 @@
 package cn.tursom.web
 
 import cn.tursom.web.utils.CacheControl
+import cn.tursom.web.utils.ContextTypeMap
 import cn.tursom.web.utils.Cookie
 import cn.tursom.web.utils.SameSite
 
@@ -53,7 +54,11 @@ interface ResponseHeaderAdapter {
   fun range(start: Int, end: Int, resourceSize: Int) = setResponseHeader("Content-Range", "$start-$end/$resourceSize")
   fun range(resourceSize: Int) = setResponseHeader("Content-Range", "*/$resourceSize")
 
+  fun setContextType(type: Any) = setResponseHeader("Content-Type", type)
+
   fun responseHtml() = setResponseHeader("content-type", "text/html; charset=UTF-8")
   fun responseText() = setResponseHeader("content-type", "text/plain; charset=UTF-8")
   fun responseJson() = setResponseHeader("content-type", "application/json; charset=UTF-8")
+
+  fun autoContextType(type: String) = setContextType(ContextTypeMap[type] ?: "application/octet-stream")
 }
\ No newline at end of file
diff --git a/web/src/main/kotlin/cn/tursom/web/router/mapping/ConnectMapping.kt b/web/src/main/kotlin/cn/tursom/web/mapping/ConnectMapping.kt
similarity index 62%
rename from web/src/main/kotlin/cn/tursom/web/router/mapping/ConnectMapping.kt
rename to web/src/main/kotlin/cn/tursom/web/mapping/ConnectMapping.kt
index 3153c15..0bace78 100644
--- a/web/src/main/kotlin/cn/tursom/web/router/mapping/ConnectMapping.kt
+++ b/web/src/main/kotlin/cn/tursom/web/mapping/ConnectMapping.kt
@@ -1,4 +1,4 @@
-package cn.tursom.web.router.mapping
+package cn.tursom.web.mapping
 
 annotation class ConnectMapping(
   vararg val route: String
diff --git a/web/src/main/kotlin/cn/tursom/web/router/mapping/DeleteMapping.kt b/web/src/main/kotlin/cn/tursom/web/mapping/DeleteMapping.kt
similarity index 62%
rename from web/src/main/kotlin/cn/tursom/web/router/mapping/DeleteMapping.kt
rename to web/src/main/kotlin/cn/tursom/web/mapping/DeleteMapping.kt
index e53447d..44b2695 100644
--- a/web/src/main/kotlin/cn/tursom/web/router/mapping/DeleteMapping.kt
+++ b/web/src/main/kotlin/cn/tursom/web/mapping/DeleteMapping.kt
@@ -1,4 +1,4 @@
-package cn.tursom.web.router.mapping
+package cn.tursom.web.mapping
 
 annotation class DeleteMapping(
   vararg val route: String
diff --git a/web/src/main/kotlin/cn/tursom/web/router/mapping/GetMapping.kt b/web/src/main/kotlin/cn/tursom/web/mapping/GetMapping.kt
similarity index 61%
rename from web/src/main/kotlin/cn/tursom/web/router/mapping/GetMapping.kt
rename to web/src/main/kotlin/cn/tursom/web/mapping/GetMapping.kt
index 6d33d3e..a75c2be 100644
--- a/web/src/main/kotlin/cn/tursom/web/router/mapping/GetMapping.kt
+++ b/web/src/main/kotlin/cn/tursom/web/mapping/GetMapping.kt
@@ -1,4 +1,4 @@
-package cn.tursom.web.router.mapping
+package cn.tursom.web.mapping
 
 annotation class GetMapping(
   vararg val route: String
diff --git a/web/src/main/kotlin/cn/tursom/web/router/mapping/HeadMapping.kt b/web/src/main/kotlin/cn/tursom/web/mapping/HeadMapping.kt
similarity index 61%
rename from web/src/main/kotlin/cn/tursom/web/router/mapping/HeadMapping.kt
rename to web/src/main/kotlin/cn/tursom/web/mapping/HeadMapping.kt
index 553a461..6ce01c2 100644
--- a/web/src/main/kotlin/cn/tursom/web/router/mapping/HeadMapping.kt
+++ b/web/src/main/kotlin/cn/tursom/web/mapping/HeadMapping.kt
@@ -1,4 +1,4 @@
-package cn.tursom.web.router.mapping
+package cn.tursom.web.mapping
 
 annotation class HeadMapping(
   vararg val route: String
diff --git a/web/src/main/kotlin/cn/tursom/web/router/mapping/Mapping.kt b/web/src/main/kotlin/cn/tursom/web/mapping/Mapping.kt
similarity index 68%
rename from web/src/main/kotlin/cn/tursom/web/router/mapping/Mapping.kt
rename to web/src/main/kotlin/cn/tursom/web/mapping/Mapping.kt
index ed062e4..d70711f 100644
--- a/web/src/main/kotlin/cn/tursom/web/router/mapping/Mapping.kt
+++ b/web/src/main/kotlin/cn/tursom/web/mapping/Mapping.kt
@@ -1,4 +1,4 @@
-package cn.tursom.web.router.mapping
+package cn.tursom.web.mapping
 
 annotation class Mapping(
   vararg val route: String,
diff --git a/web/src/main/kotlin/cn/tursom/web/router/mapping/OptionsMapping.kt b/web/src/main/kotlin/cn/tursom/web/mapping/OptionsMapping.kt
similarity index 62%
rename from web/src/main/kotlin/cn/tursom/web/router/mapping/OptionsMapping.kt
rename to web/src/main/kotlin/cn/tursom/web/mapping/OptionsMapping.kt
index e343b00..1c33822 100644
--- a/web/src/main/kotlin/cn/tursom/web/router/mapping/OptionsMapping.kt
+++ b/web/src/main/kotlin/cn/tursom/web/mapping/OptionsMapping.kt
@@ -1,4 +1,4 @@
-package cn.tursom.web.router.mapping
+package cn.tursom.web.mapping
 
 annotation class OptionsMapping(
   vararg val route: String
diff --git a/web/src/main/kotlin/cn/tursom/web/router/mapping/PatchMapping.kt b/web/src/main/kotlin/cn/tursom/web/mapping/PatchMapping.kt
similarity index 61%
rename from web/src/main/kotlin/cn/tursom/web/router/mapping/PatchMapping.kt
rename to web/src/main/kotlin/cn/tursom/web/mapping/PatchMapping.kt
index 22d8066..61285e2 100644
--- a/web/src/main/kotlin/cn/tursom/web/router/mapping/PatchMapping.kt
+++ b/web/src/main/kotlin/cn/tursom/web/mapping/PatchMapping.kt
@@ -1,4 +1,4 @@
-package cn.tursom.web.router.mapping
+package cn.tursom.web.mapping
 
 annotation class PatchMapping(
   vararg val route: String
diff --git a/web/src/main/kotlin/cn/tursom/web/router/mapping/PostMapping.kt b/web/src/main/kotlin/cn/tursom/web/mapping/PostMapping.kt
similarity index 61%
rename from web/src/main/kotlin/cn/tursom/web/router/mapping/PostMapping.kt
rename to web/src/main/kotlin/cn/tursom/web/mapping/PostMapping.kt
index b5f22be..906cf67 100644
--- a/web/src/main/kotlin/cn/tursom/web/router/mapping/PostMapping.kt
+++ b/web/src/main/kotlin/cn/tursom/web/mapping/PostMapping.kt
@@ -1,4 +1,4 @@
-package cn.tursom.web.router.mapping
+package cn.tursom.web.mapping
 
 annotation class PostMapping(
   vararg val route: String
diff --git a/web/src/main/kotlin/cn/tursom/web/router/mapping/PutMapping.kt b/web/src/main/kotlin/cn/tursom/web/mapping/PutMapping.kt
similarity index 61%
rename from web/src/main/kotlin/cn/tursom/web/router/mapping/PutMapping.kt
rename to web/src/main/kotlin/cn/tursom/web/mapping/PutMapping.kt
index f6e1622..2cfa1b2 100644
--- a/web/src/main/kotlin/cn/tursom/web/router/mapping/PutMapping.kt
+++ b/web/src/main/kotlin/cn/tursom/web/mapping/PutMapping.kt
@@ -1,4 +1,4 @@
-package cn.tursom.web.router.mapping
+package cn.tursom.web.mapping
 
 annotation class PutMapping(
   vararg val route: String
diff --git a/web/src/main/kotlin/cn/tursom/web/router/mapping/TraceMapping.kt b/web/src/main/kotlin/cn/tursom/web/mapping/TraceMapping.kt
similarity index 61%
rename from web/src/main/kotlin/cn/tursom/web/router/mapping/TraceMapping.kt
rename to web/src/main/kotlin/cn/tursom/web/mapping/TraceMapping.kt
index 0bbe973..f891b1e 100644
--- a/web/src/main/kotlin/cn/tursom/web/router/mapping/TraceMapping.kt
+++ b/web/src/main/kotlin/cn/tursom/web/mapping/TraceMapping.kt
@@ -1,4 +1,4 @@
-package cn.tursom.web.router.mapping
+package cn.tursom.web.mapping
 
 annotation class TraceMapping(
   vararg val route: String
diff --git a/web/src/main/kotlin/cn/tursom/web/result/Html.kt b/web/src/main/kotlin/cn/tursom/web/result/Html.kt
new file mode 100644
index 0000000..4645d96
--- /dev/null
+++ b/web/src/main/kotlin/cn/tursom/web/result/Html.kt
@@ -0,0 +1,3 @@
+package cn.tursom.web.result
+
+annotation class Html
\ No newline at end of file
diff --git a/web/src/main/kotlin/cn/tursom/web/result/Json.kt b/web/src/main/kotlin/cn/tursom/web/result/Json.kt
new file mode 100644
index 0000000..8316d39
--- /dev/null
+++ b/web/src/main/kotlin/cn/tursom/web/result/Json.kt
@@ -0,0 +1,3 @@
+package cn.tursom.web.result
+
+annotation class Json
\ No newline at end of file
diff --git a/web/src/main/kotlin/cn/tursom/web/result/Text.kt b/web/src/main/kotlin/cn/tursom/web/result/Text.kt
new file mode 100644
index 0000000..eaa40c7
--- /dev/null
+++ b/web/src/main/kotlin/cn/tursom/web/result/Text.kt
@@ -0,0 +1,3 @@
+package cn.tursom.web.result
+
+annotation class Text
\ No newline at end of file
diff --git a/web/src/main/kotlin/cn/tursom/web/router/RoutedHttpHandler.kt b/web/src/main/kotlin/cn/tursom/web/router/RoutedHttpHandler.kt
index f1e52e3..ed5ecfb 100644
--- a/web/src/main/kotlin/cn/tursom/web/router/RoutedHttpHandler.kt
+++ b/web/src/main/kotlin/cn/tursom/web/router/RoutedHttpHandler.kt
@@ -1,11 +1,15 @@
 package cn.tursom.web.router
 
+import cn.tursom.core.buffer.ByteBuffer
 import cn.tursom.json.JsonWorkerImpl
 import cn.tursom.web.ExceptionContent
 import cn.tursom.web.HttpContent
 import cn.tursom.web.HttpHandler
 import cn.tursom.web.router.impl.SimpleRouter
-import cn.tursom.web.router.mapping.*
+import cn.tursom.web.mapping.*
+import cn.tursom.web.result.Html
+import cn.tursom.web.result.Json
+import cn.tursom.web.result.Text
 import cn.tursom.web.utils.Chunked
 import org.slf4j.LoggerFactory
 import java.io.File
@@ -50,10 +54,9 @@ open class RoutedHttpHandler<T : HttpContent, in E : ExceptionContent>(
     @Suppress("LeakingThis")
     val clazz = handler.javaClass
     clazz.methods.forEach { method ->
+      log?.debug("try mapping {}", method)
       method.parameterTypes.let {
-        if (it.size != 1 || !HttpContent::class.java.isAssignableFrom(it[0])) {
-          return@forEach
-        } else if (it.isNotEmpty()) {
+        if (!(it.size == 1 && HttpContent::class.java.isAssignableFrom(it[0])) && it.isNotEmpty()) {
           return@forEach
         }
       }
@@ -128,15 +131,11 @@ open class RoutedHttpHandler<T : HttpContent, in E : ExceptionContent>(
         router[safeRoute(route)] = handler@{ content ->
           if (method.parameterTypes.isEmpty()) {
             val result = method(obj) ?: return@handler
-            when (result) {
-              is String -> content.finishHtml(result.toByteArray())
-              is ByteArray -> content.finishText(result)
-              is File -> content.finishFile(result)
-              is RandomAccessFile -> content.finishFile(result)
-              is Chunked -> content.finishChunked(result)
-              else -> json?.let {
-                content.finishJson(json.toJson(result)!!.toByteArray())
-              } ?: content.finishText(result.toString().toByteArray())
+            when {
+              method.getAnnotation(Html::class.java) != null -> finishHtml(result, content)
+              method.getAnnotation(Text::class.java) != null -> finishText(result, content)
+              method.getAnnotation(Json::class.java) != null -> finishJson(result, content)
+              else -> autoReturn(result, content)
             }
           } else {
             method(obj, content)
@@ -173,5 +172,48 @@ open class RoutedHttpHandler<T : HttpContent, in E : ExceptionContent>(
     }
 
     private fun safeRoute(route: String) = if (route.first() == '/') route else "/$route"
+
+    private fun autoReturn(result: Any, content: HttpContent) = when (result) {
+      is String -> content.finishText(result.toByteArray())
+      is ByteArray -> content.finishText(result)
+      is File -> {
+        content.autoContextType(result.name)
+        content.finishFile(result)
+      }
+      is RandomAccessFile -> content.finishFile(result)
+      is Chunked -> content.finishChunked(result)
+      else -> finishJson(result, content)
+    }
+
+    private fun finishHtml(result: Any, content: HttpContent) = when (result) {
+      is ByteBuffer -> content.finishHtml(result)
+      is ByteArray -> content.finishHtml(result)
+      is String -> content.finishHtml(result.toByteArray())
+      else -> content.finishHtml(result.toString().toByteArray())
+    }
+
+    private fun finishText(result: Any, content: HttpContent) = when (result) {
+      is ByteBuffer -> content.finishText(result)
+      is ByteArray -> content.finishText(result)
+      is String -> content.finishText(result.toByteArray())
+      else -> content.finishText(result.toString().toByteArray())
+    }
+
+    private fun finishJson(result: Any, content: HttpContent) {
+      when (result) {
+        is ByteBuffer -> content.finishJson(result)
+        is ByteArray -> content.finishJson(result)
+        is String -> content.finishJson("\"$result\"".toByteArray())
+        is Byte, Short, Int, Long, Float, Double, Boolean -> content.finishJson(result.toString().toByteArray())
+        else -> {
+          val json = json?.toJson(result)?.toByteArray()
+          if (json != null) {
+            content.finishJson(json)
+          } else {
+            content.finishText(result.toString().toByteArray())
+          }
+        }
+      }
+    }
   }
 }
diff --git a/web/src/main/kotlin/cn/tursom/web/utils/ContextTypeMap.kt b/web/src/main/kotlin/cn/tursom/web/utils/ContextTypeMap.kt
new file mode 100644
index 0000000..d2e2ef7
--- /dev/null
+++ b/web/src/main/kotlin/cn/tursom/web/utils/ContextTypeMap.kt
@@ -0,0 +1,83 @@
+package cn.tursom.web.utils
+
+import cn.tursom.core.datastruct.StringRadixTree
+
+object ContextTypeMap {
+  private val router = StringRadixTree<String>()
+  operator fun get(type: String) = router[type.substringAfterLast('.')]
+
+  init {
+    router["aac"] = "audio/aac"
+    router["abw"] = "application/x-abiword"
+    router["arc"] = "application/x-freearc"
+    router["avi"] = "video/x-msvideo"
+    router["azw"] = "aapplication/vnd.amazon.ebook"
+    router["bin"] = "application/octet-stream"
+    router["bmp"] = "image/bmp"
+    router["bz"] = "application/x-bzip"
+    router["bz2"] = "application/x-bzip2"
+    router["csh"] = "application/x-csh"
+    router["css"] = "itext/css; charset=UTF-8"
+    router["csv"] = "itext/csv; charset=UTF-8"
+    router["doc"] = "application/msword"
+    router["docx"] = "application/vnd.openxmlformats-officedocument.wordprocessingml.document"
+    router["eot"] = "application/vnd.ms-fontobject"
+    router["epub"] = "application/epub+zip"
+    router["gif"] = "image/gif"
+    router["html"] = "text/html; charset=UTF-8"
+    router["htm"] = "text/html; charset=UTF-8"
+    router["ico"] = "image/vnd.microsoft.icon"
+    router["ics"] = "text/calendar; charset=UTF-8"
+    router["jar"] = "application/java-archive"
+    router["jpeg"] = "image/jpeg"
+    router["jpg"] = "image/jpeg"
+    router["js"] = "text/javascript; charset=UTF-8"
+    router["json"] = "application/json; charset=UTF-8"
+    router["jsonld"] = "application/ld+json"
+    router["mid"] = "audio/midi"
+    router["midi"] = "audio/midi"
+    router["mjs"] = "text/javascript"
+    router["mp3"] = "audio/mpeg"
+    router["mp4"] = "audio/mp4"
+    router["mpeg"] = "video/mpeg"
+    router["mpkg"] = "application/vnd.apple.installer+xml"
+    router["odp"] = "application/vnd.oasis.opendocument.presentation"
+    router["ods"] = "application/vnd.oasis.opendocument.spreadsheet"
+    router["odt"] = "application/vnd.oasis.opendocument.text"
+    router["oga"] = "audio/ogg"
+    router["ogg"] = "application/ogg"
+    router["ogv"] = "video/ogg"
+    router["ogx"] = "application/ogg"
+    router["otf"] = "font/otf"
+    router["png"] = "image/png"
+    router["pdf"] = "application/pdf"
+    router["ppt"] = "application/vnd.ms-powerpoint"
+    router["pptx"] = "application/vnd.openxmlformats-officedocument.presentationml.presentation"
+    router["rar"] = "application/x-rar-compressed"
+    router["rtf"] = "application/rtf"
+    router["sh"] = "application/x-sh"
+    router["svg"] = "image/svg+xml"
+    router["swf"] = "application/x-shockwave-flash"
+    router["tar"] = "application/x-tar"
+    router["tif"] = "image/tiff"
+    router["tiff"] = "image/tiff"
+    router["ttf"] = "font/ttf"
+    router["txt"] = "text/plain; charset=UTF-8"
+    router["vsd"] = "application/vnd.visio"
+    router["wav"] = "audio/wav"
+    router["weba"] = "audio/webm"
+    router["webm"] = "video/webm"
+    router["webp"] = "image/webp"
+    router["woff"] = "font/woff"
+    router["woff2"] = "font/woff2"
+    router["xhtml"] = "application/xhtml+xml"
+    router["xls"] = "application/vnd.ms-excel"
+    router["xlsx"] = "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet"
+    router["xml"] = "text/xml; charset=UTF-8"
+    router["xul"] = "application/vnd.mozilla.xul+xml"
+    router["zip"] = "application/zip"
+    router["3gp"] = "video/3gpp"
+    router["3g2"] = "ivideo/3gpp2"
+    router["7z"] = "application/x-7z-compressed"
+  }
+}
\ No newline at end of file