java上传文件常见几种方式

1、ServletFileUpload

　　表单提交中当提交数据类型是multipare/form-data类型的时候，如果我们用servlet去做处理的话，该http请求就会被servlet容器，包装成httpservletRequest对象

　　，在由相应的servlet进行处理。

    

package com.jws.app.operater.service.impl;

import java.io.File;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;

import javax.annotation.Resource;
import javax.servlet.http.HttpServletRequest;

import org.apache.commons.fileupload.FileItem;
import org.apache.commons.fileupload.FileItemFactory;
import org.apache.commons.fileupload.disk.DiskFileItemFactory;
import org.apache.commons.fileupload.servlet.ServletFileUpload;
import org.apache.log4j.Logger;
import org.springframework.stereotype.Service;

import net.sf.json.JSONObject;

import com.jws.app.operater.data.UserInfoMapper;
import com.jws.app.operater.model.UserInfo;
import com.jws.app.operater.service.PersionPhoteAuthServer;
import com.jws.common.constant.Constants;
import com.jws.common.constant.ConstantsCode;
import com.jws.common.util.JiveGlobe;
import com.jws.common.util.ResultPackaging;

@Service("persionPhoteAuthServerImpl")
public class PersionPhoteAuthServerImpl implements PersionPhoteAuthServer {
    @Resource
    private UserInfoMapper userInfoMapper;
    private final Logger logger = Logger.getLogger(this.getClass());

    @Override
    public JSONObject uploadPhoto(HttpServletRequest reques) {
        JSONObject returnObject = new JSONObject();
        String path =  Constants.imageUrl;
        File repositoryFile = new File(path);
        if (!repositoryFile.exists()) {repositoryFile.mkdirs();}
        FileItemFactory factory = new DiskFileItemFactory(1024 * 32,repositoryFile);
        ServletFileUpload upload = new ServletFileUpload(factory);
        upload.setHeaderEncoding("utf-8");
        upload.setSizeMax(1024 * 1024 * 500);
        List<?> fileItr = null;
        try {
             fileItr = upload.parseRequest(reques);
                // 讲非文件值放在map中
                HashMap<String, String> map = new HashMap<>();
                Iterator<?> iter = fileItr.iterator();
                while (iter.hasNext()) {
                    FileItem item = (FileItem) iter.next();
                    if (item.isFormField()) {
                        map.put(item.getFieldName(), item.getString());
                    }
                }
                // 验证参数
                if (map == null || !map.containsKey("openid")) {
                    returnObject =ResultPackaging.dealJsonObject(ConstantsCode.RESULT_CODE_FAIL, ConstantsCode.CODE_LACK_PARAMETER, null);
                    return returnObject;            
                }
                String openid  = map.get("openid");
                //处理文件
                boolean isTrue = true;
                String filename = "";
                Iterator<?> iter1 = fileItr.iterator();
                while (iter1.hasNext()) {
                    FileItem f = (FileItem) iter1.next();
                    if (!f.isFormField()) {
                //详情 name=abc.png,  size=376507 bytes,     isFormField=false, FieldName=picture1
                        filename = f.getName() == null ? "" : f.getName();
                        filename = JiveGlobe.getFromRom()+".jpg";
                        File saveFile = new File(path, filename);
                        if (saveFile.exists()) {
                            isTrue = false;break;}
                            f.write(saveFile);
                        } 
            }
            if(JiveGlobe.isEmpty(filename)){
                returnObject =ResultPackaging.dealJsonObject(ConstantsCode.RESULT_CODE_FAIL, ConstantsCode.CODE_LACK_PARAMETER, null);
                return returnObject;            
            }
            returnObject =ResultPackaging.dealJsonObject(ConstantsCode.RESULT_CODE_SUCCESS, ConstantsCode.RESULT_CODE_SUCCESS, null);
            //保存文件信息
            UserInfo rd = new UserInfo();
            rd.setSpareField1("1");
            rd.setSpareField3(filename);
            rd.setOpenId(openid);
            userInfoMapper.updateByPrimaryKey(rd);
        } catch (Exception e) {
            System.out.println(e);
            logger.error("###认证失败"+e);
        }
        return returnObject;
    }
    
    
}

2、MultipartFile

   

@RequestMapping("/upload")
    @ResponseBody
    public String handleFileUpload(@RequestParam("file") MultipartFile file) {

        if (file.isEmpty()) {
            return "文件为空";
        }
        // 获取文件名
        String fileName = file.getOriginalFilename();
        System.out.println("上传的文件名为：" + fileName);
        // 获取文件的后缀名
        String suffixName = fileName.substring(fileName.lastIndexOf("."));
        System.out.println("上传的后缀名为：" + suffixName);
        // 文件上传后的路径
        String filePath = "D://";
        File dest = new File(filePath + fileName);
        // 检测是否存在目录
        if (!dest.getParentFile().exists()) {
            dest.getParentFile().mkdirs();
        }
        try {
            file.transferTo(dest);
            return "上传成功";
        } catch (IllegalStateException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
        return "上传失败";
    }

/**
     * 多文件具体上传时间，主要是使用了MultipartHttpServletRequest和MultipartFile
     * 
     * @param request
     * @return
     */
    @RequestMapping(value = "/batch/upload", method = RequestMethod.POST)
    public @ResponseBody String handleFileUpload1(HttpServletRequest request) {
        List<MultipartFile> files = ((MultipartHttpServletRequest) request).getFiles("file");
        String filePath = "D://";
        MultipartFile file = null;

        for (int i = 0; i < files.size(); ++i) {
            file = files.get(i);
            // 获取文件名
            String fileName = file.getOriginalFilename();
            System.out.println("上传的文件名为：" + fileName);

            if (!file.isEmpty()) {
                File dest = new File(filePath + fileName);
                // 检测是否存在目录
                if (!dest.getParentFile().exists()) {
                    dest.getParentFile().mkdirs();
                }
                try {
                    file.transferTo(dest);
                } catch (Exception e) {
                    return "上传失败 " + i + " => " + e.getMessage();
                }
            } else {
                return "上传失败 " + i + " 文件为空.";
            }
        }
        return "上传成功";
    }

3、CommonsMultipartResolver

　　

 *
     * @param request
     * @return
     */
    @ResponseBody
    @RequestMapping("/uploadFile")
    public Map<String, Object> uploadFile(HttpServletRequest request) {
        Map<String, Object> map = new HashMap<String, Object>();
        // 将当前上下文初始化给 CommonsMutipartResolver （多部分解析器）
        CommonsMultipartResolver multipartResolver = new CommonsMultipartResolver(request.getSession().getServletContext());
        // 检查form中是否有enctype="multipart/form-data"
        if (multipartResolver.isMultipart(request)) {
            // 将request变成多部分request
            MultipartHttpServletRequest multiRequest = (MultipartHttpServletRequest) request;
            // 获取multiRequest 中所有的文件名
            Iterator iter = multiRequest.getFileNames();
            while (iter.hasNext()) {
                // 一次遍历所有文件
                MultipartFile file = multiRequest.getFile(iter.next().toString());
                try {
                    if (file != null && StringUtils.isNotBlank(file.getOriginalFilename().trim())) {
                        Map<String, String> metas = new HashMap<String, String>();
                        // 取得文件后缀
                        String filename = file.getOriginalFilename();
                        String newFileName = System.currentTimeMillis() + (int) (Math.random() * 100)
                                + filename.substring(filename.lastIndexOf("."));
                        metas.put(StorageConstants.META_KEY_FILENAME, newFileName);
                        String imgUrl = storageService.store(file.getBytes(), metas);
                        map.put("imgUrl", imgUrl);
                        map.put("retCode", "success");
                        // map.put("imgUrl",
                        // "https://ss1.bdstatic.com/70cFuXSh_Q1YnxGkpoWK1HF6hhy/it/u=611483611,2895064642&fm=117&gp=0.jpg");
                    }
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
        } else {
            map.put("retCode", "error");
        }
        return map;