一个简单的页面上传文件，上传的接口是/upload,请求方法是post，enctype（表单类型）是multipart/form-data
<!DOCTYPE html><html lang="en"><head><meta charset="UTF-8"><title>Title</title></head><body><form action="/upload" method="post" enctype="multipart/form-data"><input type="file" name="uploadFile" value="请选择文件" multiple><input type="submit" value="上传"></form></body></html>
在项目中新建一个webapp/uploadFile的文件夹
接下来编写文件上传的controller接口：
import java.io.File;import java.io.IOException;import java.text.SimpleDateFormat;import java.util.Date;import java.util.UUID;import javax.servlet.http.HttpServletRequest;import org.springframework.stereotype.Controller;import org.springframework.web.bind.annotation.PostMapping;import org.springframework.web.bind.annotation.RequestMapping;import org.springframework.web.bind.annotation.ResponseBody;import org.springframework.web.multipart.MultipartFile;@Controllerpublic class controller {SimpleDateFormat sdf = new SimpleDateFormat("yyyy/MM/dd/");@RequestMapping("/test")public String test() {return "upload";}@PostMapping("/upload")@ResponseBodypublic String upload(MultipartFile uploadFile, HttpServletRequest req) {//获取uploadFile文件在该项目的绝对路径String realPath = req.getSession().getServletContext().getRealPath("/uploadFile/");System.out.println("realPath:" + realPath);String format = sdf.format(new Date());File folder = new File(realPath + format);System.out.println("folder:" + folder);//若果不存在该文件夹，则新建if (!folder.isDirectory()) {folder.mkdirs();}String oldName = uploadFile.getOriginalFilename();String newName = UUID.randomUUID().toString() + oldName.substring(oldName.lastIndexOf("."), oldName.length());try {uploadFile.transferTo(new File(folder, newName));System.out.println("保存文件成功");String filePath = req.getScheme() + "://" + req.getServerName() + ":" + req.getServerPort() + "/uploadFile/"+ format + newName;return filePath;} catch (IOException e) {// e.printStackTrace();}return "上传失败!";}}
全局异常之上传文件超过了限制大小
@ControllerAdvice是最常见的全局异常处理。
@ControllerAdvice结合@ExceptionHandler客户以定义全局异常捕获机制！
import java.io.IOException;import org.springframework.web.bind.annotation.ControllerAdvice;import org.springframework.web.bind.annotation.ExceptionHandler;import org.springframework.web.multipart.MaxUploadSizeExceededException;import org.springframework.web.servlet.ModelAndView;@ControllerAdvicepublic class CustomExceptionHandler {@ExceptionHandler(MaxUploadSizeExceededException.class)public ModelAndView uploadException(MaxUploadSizeExceededException e) throws IOException {ModelAndView mv = new ModelAndView();mv.addObject("msg", "最大上传文件为1M，上传文件大小超出限制!");mv.setViewName("error");return mv;}@ExceptionHandler(Exception.class)public void myexce(Exception e) {System.out.println("myexce>>>"+e.getMessage());}}
新建一个报错页面：
<!DOCTYPE html><html><head><meta charset="UTF-8"><title>Insert title here</title></head><body> <div th:text="${msg}"></div></body></html>
