ssh三层框架——上传文件(大小格式筛选+json返回相对地址)

上传文件

参考文章有三种上传方式http://wiki.jikexueyuan.com/project/ssh-noob-learning/upload-file.html

1：在struts中配置

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE struts PUBLIC
    "-//Apache Software Foundation//DTD Struts Configuration 2.0//EN"
    "http://struts.apache.org/dtds/struts-2.0.dtd">

<struts>
    <constant name="struts.il8n.encoding" value="UTF-8" />

    <constant name="struts.action.extension" value=","></constant>    
    <!-- 上传文件最大限制（如果为多文件上传，则为多个文件的总大小） -->    
    <constant name="struts.multipart.maxSize" value="40000000"></constant>    
    <!-- 存放上传文件的临时目录 -->    
    <constant name="struts.multipart.saveDir" value="D:\\temp"></constant>      

    <!-- 注意使用的包不是struts-default 而是json-default -->
    <package name="myPackage" namespace="/" extends="json-default">     
        <action name="upImgAction" class = "infoAction" method="upImg">
            <!-- param是参数，能够到action中 -->
            <param name="maximumSize ">1000000</param>  
            <!-- 这里写需要的格式待会儿会用到检验格式 -->  
            <param name="allowedTypes">image/png,image/jpg,image/jpeg,image/gif</param>     
        </action>
    </package>
</struts>

2：action

采用表单注入

//上传文件，采用表单形式，注入
private File upload;                  //上传文件
private String uploadFileName;        //上传文件名
private String uploadContentType;     //上传文件类型

private long maximumSize;  
private String allowedTypes;  

public File getUpload() {  
    return upload;  
}  
public void setUpload(File upload) {  
    this.upload = upload;  
}  
public String getUploadFileName() {  
    return uploadFileName;  
}  
public void setUploadFileName(String uploadFileName) {  
    this.uploadFileName = uploadFileName;  
}  

public String getUploadContentType() {  
    return uploadContentType;  
}  
public void setUploadContentType(String uploadContentType) {  
    this.uploadContentType = uploadContentType;  
}  
public long getMaximumSize() {  
    return maximumSize;  
}  
public void setMaximumSize(long maximumSize) {  
    this.maximumSize = maximumSize;  
}  
public String getAllowedTypes() {  
    return allowedTypes;  
}  
public void setAllowedTypes(String allowedTypes) {  
    this.allowedTypes = allowedTypes;  
}  

//上传头像
public String upImg() throws IOException {
        System.out.println("upImg...action...");

        HttpServletResponse response = ServletActionContext.getResponse();
        response.setContentType("application/json;charset=utf-8");
        response.setHeader("Access-Control-Allow-Origin", "*");
        PrintWriter outt = response.getWriter();

        JSONObject json = new JSONObject();
        try{
            //上传文件
            String flag = infoService.upFile(maximumSize,allowedTypes,upload,uploadFileName,uploadContentType);

            //地址为上传成功   0失败  -1太大  -2类型不符合
            json.put("msg", flag);

        } catch (Exception e) {
            System.out.println(e.toString());
            json.put("msg", "0");                    //失败
        } finally {
            outt.write(json.toString());
            outt.flush();
            outt.close();
        }

        return null;
    }
}

3：service中

//上传文件
public String upFile(long maximumSize, String allowedTypes, File upload, String uploadFileName,
        String uploadContentType) {
    System.out.println("upFile...service...");
    HttpSession session = ServletActionContext.getRequest().getSession();

    try{
        //新建文件
        File uploadFile = new File(ServletActionContext.getServletContext().getRealPath("upload"));
        if(!uploadFile.exists()) {  
            uploadFile.mkdir();  
        } 

        //验证文件大小
        if (maximumSize < upload.length()) {  
            return "-1";                        //文件过大

        } else {
            //验证文件格式
            boolean flag = false;  
            String[]  allowedTypesStr = allowedTypes.split(",");    //这是在配置文件中 按照逗号隔开

            for (int i = 0; i < allowedTypesStr.length; i++) {  
                if (uploadContentType.equals(allowedTypesStr[i])) {  
                    flag = true;                              
                }  
            }  

            if (flag == false) {  
                return "-2";                     //文件格式错误

            } else {
                //文件名为"uid_img"+uid+"后缀"
                String[] uploadFileNameArray = uploadFileName.split("\\.");
                uploadFileName = "uid_img" + session.getAttribute("uid") + "." + uploadFileNameArray[1];
                String path = uploadFile.getPath()+ "\\" + uploadFileName;

                //准备上传
                FileUtils.copyFile(upload, new File(path));  
                //删除临时文件  
                upload.delete(); 

                //相对路径
                String rePath = "upload" + "\\" + uploadFileName;
                //写入数据库
                boolean flag2 = infoDao.upImg((int)session.getAttribute("uid"), rePath);
                if(flag2 == false) {
                    return "0";                //失败
                } else { 
                    System.out.println(ServletActionContext.getServletContext().getContextPath());
                    return rePath;               //成功
                }

            }
        }
    } catch (Exception e) {
        System.out.println(e.toString());
        return "0";
    }

}

4：dao

//写入头像地址
@Override
public boolean upImg(int uid, String path) {
    System.out.println("upImg...dao...");

    try{
        User user = hibernateTemplate.get(User.class, uid);
        user.setPhoto(path);
        return true;
    }catch (Exception e) {
        System.out.println(e.toString());
        return false;
    }
}