springmvc处理上传图片代码(校验图片尺寸、图片大小)

package com.maizuo.web.controller;

import com.maizuo.domain.Result;
import com.maizuo.util.ConstantsConfig;
import com.maizuo.util.Upload;
import hyxlog.Log;
import net.sf.json.JSONObject;
import org.apache.commons.lang.StringUtils;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.*;
import org.springframework.web.multipart.MultipartFile;
import javax.imageio.ImageIO;
import javax.servlet.http.HttpServletRequest;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.util.Date;
import java.util.List;

/**
 * Created by qiyang on 2015/6/15 and improved by heisenberg on 2016/04/18
 */
@Controller
@RequestMapping("/api/upload")
public class UploadController {
    @RequestMapping(value = "/img", method = RequestMethod.POST)
    @ResponseBody
    public Result uploadImg(@RequestParam(value = "file", required = false) MultipartFile file, String pathName,
            Integer sizeRule, Integer isDeviation, HttpServletRequest request)
                    throws FileNotFoundException, IOException {
        String loghead = "通用接口-上传图片:";

        JSONObject json = new JSONObject();
        if (file == null) {
            Log.info(loghead + "上传失败:文件为空");
            return new Result(900001, "", "上传失败:文件为空");
        }
        if (StringUtils.isBlank(pathName)) {
            pathName = ConstantsConfig.getString("DEFALTUPLOADPATH");
        }
        List<Object> uploadPathNames = ConstantsConfig.getList("UPLOADPATHNAMES");
        boolean flag = false;
        for (int i = 0; i < uploadPathNames.size(); i++) {
            if (pathName.equals(uploadPathNames.get(i))) {
                flag = true;
            }
        }
        if (!flag) {
            Log.info(loghead + "上传失败:上传路径无效");
            return new Result(900001, "", "上传失败:上传路径无效");
        }
        String fileName = file.getOriginalFilename();
        // 获取上传文件扩展名
        String fileExt = fileName.substring(fileName.lastIndexOf(".") + 1, fileName.length());
        // 对扩展名进行小写转换
        fileExt = fileExt.toLowerCase();
        // 图片文件大小过滤
        if (!"jpg".equals(fileExt) && !"jpeg".equals(fileExt) && !"png".equals(fileExt) && !"bmp".equals(fileExt)
                && !"gif".equals(fileExt)) {
            Log.info(loghead + "上传失败:无效图片文件类型");
            return new Result(900001, "", "上传失败:无效图片文件类型");
        }
        long fileSize = file.getSize();
        Log.info(loghead + "fileInfo:fileName=" + fileName + "&fileSize=" + fileSize);
        if (fileSize <= 0) {
            Log.info(loghead + "上传失败:文件为空");
            return new Result(900001, "", "上传失败:文件为空");
        } else if (fileSize > (500 * 1024)) {
            Log.info(loghead + "上传失败:文件大小不能超过500K");
            return new Result(900001, "", "上传失败:文件大小不能超过500K");
        }
        File tmpFile = null;
        // 判断文件是否为空
        if (!file.isEmpty()) {
            String uploadPath = request.getSession().getServletContext().getRealPath("/") + "/upload/";
            File uploadDir = new File(uploadPath);
            if (uploadDir.exists() && uploadDir.isDirectory()) {
                String[] childFileNameList = uploadDir.list();
                if (childFileNameList != null) {
                    File temp;
                    for (int i = 0; i < childFileNameList.length; i++) {
                        temp = new File(uploadPath + childFileNameList[i]);
                        if (temp.isFile()) {
                            temp.delete();
                        }
                    }
                }
            } else {
                uploadDir.mkdir();
            }

            try {
                Date now = new Date();
                String tmpFileName = String.valueOf(now.getTime()) + Math.round(Math.random() * 1000) + "." + fileExt;
                // 文件保存路径
                String tmpFilePath = uploadPath + tmpFileName;
                tmpFile = new File(tmpFilePath);
                file.transferTo(tmpFile);
                BufferedImage sourceImg = ImageIO.read(new FileInputStream(tmpFile));
                int imgWidth = sourceImg.getWidth();
                int imgHeight = sourceImg.getHeight();
                System.out.println("上传的图片宽：" + imgWidth);
                System.out.println("上传的图片高：" + imgHeight);
                // 图片文件尺寸过滤
                if (sizeRule == null) {
                    // 上传到图片服务器
                    String imgUrl = Upload.upload(tmpFile, "/" + pathName + "/");
                    json.put("fileName", fileName);
                    json.put("url", imgUrl);
                    json.put("imgWidth", imgWidth);
                    json.put("imgHeight", imgHeight);
                    return new Result(0, json, "success");
                } else {
                    System.out.println("前端选择图片尺寸规则" + sizeRule);
                    int ruleWidth = 0;
                    int ruleHeight = 0;
                    try {
                        String imgSizeRule = ConstantsConfig.getString("UPLOADIMG_RULE" + sizeRule);
                        String imgSizeRule_width_height[] = imgSizeRule.split(",");
                        String imgSizeRule_width = imgSizeRule_width_height[0];
                        String imgSizeRule_height = imgSizeRule_width_height[1];
                        ruleWidth = Integer.parseInt(imgSizeRule_width);
                        ruleHeight = Integer.parseInt(imgSizeRule_height);
                    } catch (Exception e) {
                        System.out.println("没有配置尺寸规则" + sizeRule);
                        json.put("fileName", fileName);
                        json.put("imgWidth", imgWidth);
                        json.put("imgHeight", imgHeight);
                        return new Result(-1, json, "配置系统没有配置上传图片尺寸规则" + sizeRule
                                + ",请前端修改参数sizeRule值或管理员在配置系统配置sizeRule" + sizeRule + "规则对应的配置项");
                    }
                    if (isDeviation == null) {
                        System.out.println("严格限制图片尺寸");
                        if (ruleWidth == imgWidth && ruleHeight == imgHeight) {
                            String imgUrl = Upload.upload(tmpFile, "/" + pathName + "/");
                            json.put("fileName", fileName);
                            json.put("url", imgUrl);
                            json.put("imgWidth", imgWidth);
                            json.put("imgHeight", imgHeight);
                            return new Result(0, json, "success");
                        } else {
                            json.put("fileName", fileName);
                            json.put("imgWidth", imgWidth);
                            json.put("imgHeight", imgHeight);
                            json.put("ruleWidth", ruleWidth);
                            json.put("ruleHeight", ruleHeight);
                            return new Result(-1, json, "请上传" + ruleWidth + "*" + ruleHeight + "px的图片");
                        }
                    } else {
                        int deviation = Integer.parseInt(ConstantsConfig.getString("UPLOADIMG_DEVIATION"));
                        System.out.println("允许尺寸误差在" + deviation + "以内");
                        if (Math.abs(ruleWidth - imgWidth) <= deviation
                                && Math.abs(ruleHeight - imgHeight) <= deviation) {
                            String imgUrl = Upload.upload(tmpFile, "/" + pathName + "/");
                            json.put("fileName", fileName);
                            json.put("url", imgUrl);
                            json.put("imgWidth", imgWidth);
                            json.put("imgHeight", imgHeight);
                            return new Result(0, json, "success");
                        } else {
                            json.put("fileName", fileName);
                            json.put("imgWidth", imgWidth);
                            json.put("imgHeight", imgHeight);
                            json.put("ruleWidth", ruleWidth);
                            json.put("ruleHeight", ruleHeight);
                            return new Result(-1, json, "请上传" + ruleWidth + "*" + ruleHeight + "px的图片");
                        }
                    }
                }
            } catch (Exception e) {
                e.printStackTrace();
                Log.info(loghead + "上传失败:文件上传失败");
                return new Result(900001, "", "上传失败:文件上传异常");
            } finally {
                // 删除临时文件
                if (tmpFile.exists()) {
                    tmpFile.deleteOnExit();
                    Log.info(loghead + "删除临时文件" + tmpFile.getAbsolutePath());
                }
            }
        }
        return new Result(-1, json, "后台校验上传图片流程异常");
    }
}

本文转自：koushr