diff --git a/rest/alien_controller.go b/rest/alien_controller.go
index 8be737b..ebb212e 100644
--- a/rest/alien_controller.go
+++ b/rest/alien_controller.go
@@ -5,7 +5,6 @@ import (
 	"net/http"
 	"regexp"
 	"strconv"
-	"strings"
 	"tank/rest/result"
 	"time"
 )
@@ -281,7 +280,7 @@ func (this *AlienController) Upload(writer http.ResponseWriter, request *http.Re
 
 	dirMatter := this.matterDao.CheckWithRootByUuid(uploadToken.FolderUuid, user)
 
-	matter := this.matterService.Upload(file, user, dirMatter, uploadToken.Filename, uploadToken.Privacy)
+	matter := this.matterService.AtomicUpload(file, user, dirMatter, uploadToken.Filename, uploadToken.Privacy)
 
 	//更新这个uploadToken的信息.
 	uploadToken.ExpireTime = time.Now()
@@ -299,6 +298,8 @@ func (this *AlienController) CrawlToken(writer http.ResponseWriter, request *htt
 	}
 
 	uploadTokenUuid := request.FormValue("uploadTokenUuid")
+	url := request.FormValue("url")
+
 	if uploadTokenUuid == "" {
 		panic("uploadTokenUuid必填")
 	}
@@ -314,22 +315,9 @@ func (this *AlienController) CrawlToken(writer http.ResponseWriter, request *htt
 
 	user := this.userDao.CheckByUuid(uploadToken.UserUuid)
 
-	url := request.FormValue("url")
-	if url == "" || (!strings.HasPrefix(url, "http://") && !strings.HasPrefix(url, "https://")) {
-		panic("资源url必填，并且应该以http://或者https://开头")
-	}
+	dirMatter := this.matterDao.CheckWithRootByUuid(uploadToken.FolderUuid, user)
 
-	var dirPath string
-	if uploadToken.FolderUuid == MATTER_ROOT {
-
-		dirPath = "/"
-	} else {
-
-		dirMatter := this.matterDao.CheckByUuid(uploadToken.FolderUuid)
-		dirPath = dirMatter.Path
-	}
-
-	matter := this.matterService.Crawl(url, uploadToken.Filename, user, uploadToken.FolderUuid, dirPath, uploadToken.Privacy)
+	matter := this.matterService.AtomicCrawl(url, uploadToken.Filename, user, dirMatter, uploadToken.Privacy)
 
 	//更新这个uploadToken的信息.
 	uploadToken.ExpireTime = time.Now()
@@ -347,6 +335,7 @@ func (this *AlienController) CrawlDirect(writer http.ResponseWriter, request *ht
 	privacyStr := request.FormValue("privacy")
 	//文件夹路径，以 / 开头。
 	dir := request.FormValue("dir")
+	url := request.FormValue("url")
 
 	if filename == "" {
 		panic("文件名必填")
@@ -354,11 +343,6 @@ func (this *AlienController) CrawlDirect(writer http.ResponseWriter, request *ht
 		panic(fmt.Sprintf(`【%s】不符合要求，文件名中不能包含以下特殊符号：< > | * ? / \`, filename))
 	}
 
-	url := request.FormValue("url")
-	if url == "" || (!strings.HasPrefix(url, "http://") && !strings.HasPrefix(url, "https://")) {
-		panic("资源url必填，并且应该以http://或者https://开头")
-	}
-
 	var privacy bool
 	if privacyStr == "" {
 		panic(`文件公有性必填`)
@@ -375,7 +359,7 @@ func (this *AlienController) CrawlDirect(writer http.ResponseWriter, request *ht
 	user := this.CheckRequestUser(writer, request)
 	dirMatter := this.matterService.CreateDirectories(user, dir)
 
-	matter := this.matterService.Crawl(url, filename, user, dirMatter.Uuid, dirMatter.Path, privacy)
+	matter := this.matterService.AtomicCrawl(url, filename, user, dirMatter, privacy)
 
 	return this.Success(matter)
 }
diff --git a/rest/dav_service.go b/rest/dav_service.go
index 0b49fc1..c5cf85b 100644
--- a/rest/dav_service.go
+++ b/rest/dav_service.go
@@ -230,10 +230,10 @@ func (this *DavService) HandlePut(writer http.ResponseWriter, request *http.Requ
 	//如果存在，那么先删除再说。
 	srcMatter := this.matterDao.findByUserUuidAndPath(user.Uuid, subPath)
 	if srcMatter != nil {
-		this.matterService.Delete(srcMatter)
+		this.matterService.AtomicDelete(srcMatter)
 	}
 
-	this.matterService.Upload(request.Body, user, dirMatter, filename, true)
+	this.matterService.AtomicUpload(request.Body, user, dirMatter, filename, true)
 
 }
 
@@ -245,7 +245,7 @@ func (this *DavService) HandleDelete(writer http.ResponseWriter, request *http.R
 	//寻找符合条件的matter.
 	matter := this.matterDao.CheckWithRootByPath(subPath, user)
 
-	this.matterService.Delete(matter)
+	this.matterService.AtomicDelete(matter)
 }
 
 //创建文件夹
@@ -259,7 +259,7 @@ func (this *DavService) HandleMkcol(writer http.ResponseWriter, request *http.Re
 	//寻找符合条件的matter.
 	dirMatter := this.matterDao.CheckWithRootByPath(dirPath, user)
 
-	this.matterService.CreateDirectory(dirMatter, thisDirName, user)
+	this.matterService.AtomicCreateDirectory(dirMatter, thisDirName, user)
 
 }
 
@@ -371,9 +371,9 @@ func (this *DavService) HandleMove(writer http.ResponseWriter, request *http.Req
 	//移动到新目录中去。
 	if destinationDirPath == srcDirPath {
 		//文件夹没变化，相当于重命名。
-		this.matterService.Rename(srcMatter, destinationName, user)
+		this.matterService.AtomicRename(srcMatter, destinationName, user)
 	} else {
-		this.matterService.Move(srcMatter, destDirMatter, overwrite)
+		this.matterService.AtomicMove(srcMatter, destDirMatter, overwrite)
 	}
 
 	this.logger.Info("完成移动 %s => %s", subPath, destDirMatter.Path)
@@ -387,7 +387,7 @@ func (this *DavService) HandleCopy(writer http.ResponseWriter, request *http.Req
 	srcMatter, destDirMatter, _, _, destinationName, overwrite := this.prepareMoveCopy(writer, request, user, subPath)
 
 	//复制到新目录中去。
-	this.matterService.Copy(srcMatter, destDirMatter, destinationName,overwrite)
+	this.matterService.AtomicCopy(srcMatter, destDirMatter, destinationName,overwrite)
 
 	this.logger.Info("完成复制 %s => %s", subPath, destDirMatter.Path)
 
diff --git a/rest/download/download.go b/rest/download/download.go
index 1feab50..c8af574 100644
--- a/rest/download/download.go
+++ b/rest/download/download.go
@@ -366,33 +366,11 @@ func DownloadFile(
 
 
 // 从指定的url下载一个文件。参考：https://golangcode.com/download-a-file-from-a-url/
-func HttpDownloadFile(filepath string, url string) (int64, error) {
-
-	// Create the file
-	out, err := os.Create(filepath)
-	if err != nil {
-		return 0, err
-	}
-	defer func() {
-		e := out.Close()
-		PanicError(e)
-	}()
+func HttpDownloadFile(url string) io.Reader {
 
 	// Get the data
 	resp, err := http.Get(url)
-	if err != nil {
-		return 0, err
-	}
-	defer func() {
-		e := resp.Body.Close()
-		PanicError(e)
-	}()
+	PanicError(err)
 
-	// Write the body to file
-	size, err := io.Copy(out, resp.Body)
-	if err != nil {
-		return 0, err
-	}
-
-	return size, nil
+	return resp.Body
 }
diff --git a/rest/matter_controller.go b/rest/matter_controller.go
index 26f2751..a15930a 100644
--- a/rest/matter_controller.go
+++ b/rest/matter_controller.go
@@ -192,7 +192,7 @@ func (this *MatterController) CreateDirectory(writer http.ResponseWriter, reques
 		dirMatter = this.matterDao.CheckByUuid(puuid)
 	}
 
-	matter := this.matterService.CreateDirectory(dirMatter, name, user);
+	matter := this.matterService.AtomicCreateDirectory(dirMatter, name, user);
 	return this.Success(matter)
 }
 
@@ -234,7 +234,7 @@ func (this *MatterController) Upload(writer http.ResponseWriter, request *http.R
 
 	dirMatter := this.matterDao.CheckWithRootByUuid(puuid, user)
 
-	matter := this.matterService.Upload(file, user, dirMatter, fileName, privacy)
+	matter := this.matterService.AtomicUpload(file, user, dirMatter, fileName, privacy)
 
 	return this.Success(matter)
 }
@@ -243,6 +243,10 @@ func (this *MatterController) Upload(writer http.ResponseWriter, request *http.R
 func (this *MatterController) Crawl(writer http.ResponseWriter, request *http.Request) *result.WebResult {
 
 	userUuid := request.FormValue("userUuid")
+	puuid := request.FormValue("puuid")
+	url := request.FormValue("url")
+	privacyStr := request.FormValue("privacy")
+
 	user := this.checkUser(writer, request)
 	if user.Role != USER_ROLE_ADMINISTRATOR {
 		userUuid = user.Uuid
@@ -254,27 +258,13 @@ func (this *MatterController) Crawl(writer http.ResponseWriter, request *http.Re
 
 	user = this.userDao.CheckByUuid(userUuid)
 
-	puuid := request.FormValue("puuid")
-	var dirRelativePath string
-	if puuid == "" {
-		this.PanicBadRequest("puuid必填")
-	} else {
-		if puuid == MATTER_ROOT {
-			dirRelativePath = ""
-		} else {
-			//找出上一级的文件夹。
-			dirMatter := this.matterDao.CheckByUuidAndUserUuid(puuid, userUuid)
-			dirRelativePath = dirMatter.Path
-		}
-	}
+	dirMatter := this.matterDao.CheckWithRootByUuid(puuid, user)
 
 	privacy := false
-	privacyStr := request.FormValue("privacy")
 	if privacyStr == TRUE {
 		privacy = true
 	}
 
-	url := request.FormValue("url")
 	if url == "" || (!strings.HasPrefix(url, "http://") && !strings.HasPrefix(url, "https://")) {
 		panic("资源url必填，并且应该以http://或者https://开头")
 	}
@@ -284,7 +274,7 @@ func (this *MatterController) Crawl(writer http.ResponseWriter, request *http.Re
 		panic("文件名必传")
 	}
 
-	matter := this.matterService.Crawl(url, filename, user, puuid, dirRelativePath, privacy)
+	matter := this.matterService.AtomicCrawl(url, filename, user, dirMatter, privacy)
 
 	return this.Success(matter)
 }
@@ -305,7 +295,7 @@ func (this *MatterController) Delete(writer http.ResponseWriter, request *http.R
 		this.PanicUnauthorized("没有权限")
 	}
 
-	this.matterService.Delete(matter)
+	this.matterService.AtomicDelete(matter)
 
 	return this.Success("删除成功！")
 }
@@ -336,7 +326,7 @@ func (this *MatterController) DeleteBatch(writer http.ResponseWriter, request *h
 			this.PanicUnauthorized("没有权限")
 		}
 
-		this.matterService.Delete(matter)
+		this.matterService.AtomicDelete(matter)
 
 	}
 
@@ -358,7 +348,7 @@ func (this *MatterController) Rename(writer http.ResponseWriter, request *http.R
 		this.PanicUnauthorized("没有权限")
 	}
 
-	this.matterService.Rename(matter, name, user)
+	this.matterService.AtomicRename(matter, name, user)
 
 	return this.Success(matter)
 }
@@ -447,7 +437,7 @@ func (this *MatterController) Move(writer http.ResponseWriter, request *http.Req
 		srcMatters = append(srcMatters, srcMatter)
 	}
 
-	this.matterService.MoveBatch(srcMatters, destMatter)
+	this.matterService.AtomicMoveBatch(srcMatters, destMatter)
 
 	return this.Success(nil)
 }
diff --git a/rest/matter_service.go b/rest/matter_service.go
index 62b7a03..b24ce5f 100644
--- a/rest/matter_service.go
+++ b/rest/matter_service.go
@@ -1,7 +1,6 @@
 package rest
 
 import (
-	"fmt"
 	"io"
 	"net/http"
 	"os"
@@ -11,6 +10,10 @@ import (
 	"tank/rest/result"
 )
 
+/**
+ * 操作文件的Service
+ * 以 Atomic 开头的方法带有操作锁，这种方法不能被其他的Atomic方法调用，只能提供给外部调用。
+ */
 //@Service
 type MatterService struct {
 	Bean
@@ -65,7 +68,7 @@ func (this *MatterService) DownloadFile(
 }
 
 //删除文件
-func (this *MatterService) Delete(matter *Matter) {
+func (this *MatterService) AtomicDelete(matter *Matter) {
 
 	if matter == nil {
 		panic(result.BadRequest("matter不能为nil"))
@@ -78,18 +81,13 @@ func (this *MatterService) Delete(matter *Matter) {
 	this.matterDao.Delete(matter)
 }
 
-//开始上传文件
-//上传文件. alien表明文件是否是应用使用的文件。
+//上传文件
 func (this *MatterService) Upload(file io.Reader, user *User, dirMatter *Matter, filename string, privacy bool) *Matter {
 
 	if user == nil {
 		panic(result.BadRequest("user cannot be nil."))
 	}
 
-	//操作锁
-	this.userService.MatterLock(user.Uuid)
-	defer this.userService.MatterUnlock(user.Uuid)
-
 	//验证dirMatter
 	if dirMatter == nil {
 		panic(result.BadRequest("dirMatter cannot be nil."))
@@ -166,6 +164,20 @@ func (this *MatterService) Upload(file io.Reader, user *User, dirMatter *Matter,
 	return matter
 }
 
+//上传文件
+func (this *MatterService) AtomicUpload(file io.Reader, user *User, dirMatter *Matter, filename string, privacy bool) *Matter {
+
+	if user == nil {
+		panic(result.BadRequest("user cannot be nil."))
+	}
+
+	//操作锁
+	this.userService.MatterLock(user.Uuid)
+	defer this.userService.MatterUnlock(user.Uuid)
+
+	return this.Upload(file, user, dirMatter, filename, privacy)
+}
+
 //内部创建文件，不带操作锁。
 func (this *MatterService) innerCreateDirectory(dirMatter *Matter, name string, user *User) *Matter {
 
@@ -241,7 +253,7 @@ func (this *MatterService) innerCreateDirectory(dirMatter *Matter, name string,
 }
 
 //在dirMatter中创建文件夹 返回刚刚创建的这个文件夹
-func (this *MatterService) CreateDirectory(dirMatter *Matter, name string, user *User) *Matter {
+func (this *MatterService) AtomicCreateDirectory(dirMatter *Matter, name string, user *User) *Matter {
 
 	//操作锁
 	this.userService.MatterLock(user.Uuid)
@@ -325,7 +337,7 @@ func (this *MatterService) innerMove(srcMatter *Matter, destDirMatter *Matter) {
 }
 
 //将一个srcMatter放置到另一个destMatter(必须为文件夹)下
-func (this *MatterService) Move(srcMatter *Matter, destDirMatter *Matter, overwrite bool) {
+func (this *MatterService) AtomicMove(srcMatter *Matter, destDirMatter *Matter, overwrite bool) {
 
 	if srcMatter == nil {
 		panic(result.BadRequest("srcMatter cannot be nil."))
@@ -358,7 +370,7 @@ func (this *MatterService) Move(srcMatter *Matter, destDirMatter *Matter, overwr
 }
 
 //将一个srcMatter放置到另一个destMatter(必须为文件夹)下
-func (this *MatterService) MoveBatch(srcMatters []*Matter, destDirMatter *Matter) {
+func (this *MatterService) AtomicMoveBatch(srcMatters []*Matter, destDirMatter *Matter) {
 
 	if destDirMatter == nil {
 		panic(result.BadRequest("destDirMatter cannot be nil."))
@@ -450,7 +462,7 @@ func (this *MatterService) innerCopy(srcMatter *Matter, destDirMatter *Matter, n
 }
 
 //将一个srcMatter复制到另一个destMatter(必须为文件夹)下，名字叫做name
-func (this *MatterService) Copy(srcMatter *Matter, destDirMatter *Matter, name string, overwrite bool) {
+func (this *MatterService) AtomicCopy(srcMatter *Matter, destDirMatter *Matter, name string, overwrite bool) {
 
 	if srcMatter == nil {
 		panic(result.BadRequest("srcMatter cannot be nil."))
@@ -471,7 +483,7 @@ func (this *MatterService) Copy(srcMatter *Matter, destDirMatter *Matter, name s
 }
 
 //将一个matter 重命名为 name
-func (this *MatterService) Rename(matter *Matter, name string, user *User) {
+func (this *MatterService) AtomicRename(matter *Matter, name string, user *User) {
 
 	if user == nil {
 		this.PanicBadRequest("user cannot be nil")
@@ -623,52 +635,25 @@ func (this *MatterService) Detail(uuid string) *Matter {
 }
 
 //去指定的url中爬文件
-func (this *MatterService) Crawl(url string, filename string, user *User, puuid string, dirRelativePath string, privacy bool) *Matter {
+func (this *MatterService) AtomicCrawl(url string, filename string, user *User, dirMatter *Matter, privacy bool) *Matter {
 
-	//文件名不能太长。
-	if len(filename) > 200 {
-		panic("文件名不能超过200")
+	if user == nil {
+		panic(result.BadRequest("user cannot be nil."))
 	}
 
-	//获取文件应该存放在的物理路径的绝对路径和相对路径。
-	absolutePath := GetUserFileRootDir(user.Username) + dirRelativePath + "/" + filename
-	relativePath := dirRelativePath + "/" + filename
+	if url == "" || (!strings.HasPrefix(url, "http://") && !strings.HasPrefix(url, "https://")) {
+		panic("资源url必填，并且应该以http://或者https://开头")
+	}
 
-	//使用临时文件存放
-	fmt.Printf("存放于%s", absolutePath)
-	size, err := download.HttpDownloadFile(absolutePath, url)
+	//操作锁
+	this.userService.MatterLock(user.Uuid)
+	defer this.userService.MatterUnlock(user.Uuid)
+
+	//从指定的url下载一个文件。参考：https://golangcode.com/download-a-file-from-a-url/
+	resp, err := http.Get(url)
 	this.PanicError(err)
 
-	//判断用户自身上传大小的限制。
-	if user.SizeLimit >= 0 {
-		if size > user.SizeLimit {
-			panic("您最大只能上传" + HumanFileSize(user.SizeLimit) + "的文件")
-		}
-	}
-
-	//查找文件夹下面是否有同名文件。
-	matters := this.matterDao.ListByUserUuidAndPuuidAndDirAndName(user.Uuid, puuid, false, filename)
-	//如果有同名的文件，那么我们直接覆盖同名文件。
-	for _, dbFile := range matters {
-		this.Delete(dbFile)
-	}
-
-	//将文件信息存入数据库中。
-	matter := &Matter{
-		Puuid:    puuid,
-		UserUuid: user.Uuid,
-		Username: user.Username,
-		Dir:      false,
-		Name:     filename,
-		Md5:      "",
-		Size:     size,
-		Privacy:  privacy,
-		Path:     relativePath,
-	}
-
-	matter = this.matterDao.Create(matter)
-
-	return matter
+	return this.Upload(resp.Body, user, dirMatter, filename, privacy)
 }
 
 //调整一个Matter的path值