如何在Spring MVC Controller中获取getServletContext()
问题内容:
我需要在项目中上传图像。如何在SpringMVC中获取上传路径。路径是;
/home/cme/project/eclipse/workspace_12_11/.metadata/.plugins/org.eclipse.wst.server.core/tmp0/wtpwebapps/fileUploadTester/upload
以下错误;
The method getServletContext() is undefined for the type HomePageController
当我使用此代码时出现;
String uploadPath = getServletContext().getRealPath("") + File.separator + UPLOAD_DIRECTORY;
我的代码是
public ModelAndView UploadPhoto(@ModelAttribute User user, HttpServletRequest request, HttpServletResponse response) throws IOException {
final String UPLOAD_DIRECTORY = "upload";
final int THRESHOLD_SIZE = 1024 * 1024 * 3; // 3MB
final int MAX_FILE_SIZE = 1024 * 1024 * 40; // 40MB
final int MAX_REQUEST_SIZE = 1024 * 1024 * 50; // 50MB
String value[] = new String[10];
int i = 0;
// checks if the request actually contains upload file
if (!ServletFileUpload.isMultipartContent(request)) {
PrintWriter writer = response.getWriter();
writer.println("Request does not contain upload data");
writer.flush();
return; //here is error This method must return a result of type ModelAndView
}
DiskFileItemFactory factory = new DiskFileItemFactory();
factory.setSizeThreshold(THRESHOLD_SIZE);
factory.setRepository(new File(System.getProperty("java.io.tmpdir")));
ServletFileUpload upload = new ServletFileUpload(factory);
upload.setFileSizeMax(MAX_FILE_SIZE); //here error The method setFileSizeMax(int) is undefined for the type ServletFileUpload
upload.setSizeMax(MAX_REQUEST_SIZE);
String uploadPath = getServletContext().getRealPath("") + File.separator + UPLOAD_DIRECTORY; // here error The method getServletContext() is undefined for the type Homepage Controller
// creates the directory if it does not exist
File uploadDir = new File(uploadPath);
if (!uploadDir.exists()) {
uploadDir.mkdir();
}
try {
List < FileItem > items = upload.parseRequest(request); // request is HttpServletRequest
for (FileItem item: items) {
if (item.isFormField()) { // text fields, etc...
String fieldName = item.getFieldName();
System.out.print("fieldname" + fieldName);
value[i] = item.getString();
System.out.print("from uploader" + value[i]);
i++;
} else {
//String fileName=new File(item.getName()).getName(); Use this to use default file name
String name = value[0];
System.out.println("file uploader name" + name);
String filePath = uploadPath + File.separator + name;
System.out.println(filePath);
File storeFile = new File(filePath);
try {
item.write(storeFile);
} catch (Exception ex) {
}
}
}
System.out.println("uploaded successfully");
} catch (Exception ex) {
System.out.println("error not uploaded");
}
return new ModelAndView("ChangePhoto");
}
三错误
- 此方法必须返回ModelAndView类型的结果
- 对于ServletFileUpload类型,未定义方法setFileSizeMax(int)
- 对于类型Homepage Controller,未定义方法getServletContext()
问题答案:
- 使用下面的代码
ServletContext
在SpringMVC中自动连接对象
@Autowired
ServletContext context;
然后尝试执行您的代码
String uploadPath = context.getRealPath("") + File.separator + UPLOAD_DIRECTORY;
- 您可以像这样在控制器中获取它;
private ServletContext context;
public void setServletContext(ServletContext servletContext) {
this.context = servletContext;
}
但是为此,您的控制器必须实现ServletContextAware
接口