使用Servlet实现上传文件功能
2021-06-10 10:02
标签：表单 span location style cti path alt ram finally 1.servlet只需加上一个注释和用request.getPart来获取文件的值，这是servlet3.0的API 2.表单需要加上一个属性enctype="multipart/form-data" 现在附上代码 表单： servlet： 在类的声名上加上这两个注释 @WebServlet(name = "FileUploadServlet", urlPatterns = {"/upload"}) 自定义的方法： processRequest方法是获取文件的值的 getFileName方法是获取文件名的 最后在doPost方法里写 到这里就全部完成了，长传成功的效果，如图： 使用Servlet实现上传文件功能 标签：表单 span location style cti path alt ram finally 原文地址：http://www.cnblogs.com/-brl/p/7296180.html form method="POST" action="upload" enctype="multipart/form-data" >
File:
input type="file" name="file" id="file" /> br/>
Destination:
input type="text" value="f:" name="destination"/>
br/>
input type="submit" value="Upload" name="upload" id="upload" />
form>
@MultipartConfigprotected void processRequest(HttpServletRequest request,
HttpServletResponse response)
throws ServletException, IOException {
response.setContentType("text/html;charset=UTF-8");
request.setCharacterEncoding("utf-8");
//获取路径
final String path = request.getParameter("destination");
//获取文件的值
final Part filePart = request.getPart("file");
System.out.println(filePart);
final String fileName = getFileName(filePart);
//使用IO流对文件进行操作
OutputStream out = null;
InputStream filecontent = null;
final PrintWriter writer = response.getWriter();
try {
out = new FileOutputStream(new File(path + File.separator
+ fileName));
filecontent = filePart.getInputStream();
int read;
final byte[] bytes = new byte[1024];
while ((read = filecontent.read(bytes)) != -1) {
out.write(bytes, 0, read);
}
writer.println("New file " + fileName + " created at " + path);
LOGGER.log(Level.INFO, "File {0} being uploaded to {1}",
new Object[]{fileName, path});
} catch (FileNotFoundException fne) {
writer.println("You either did not specify a file to upload or are "
+ "trying to upload a file to a protected or nonexistent "
+ "location.");
writer.println("
ERROR: " + fne.getMessage());
LOGGER.log(Level.SEVERE, "Problems during file upload. Error: {0}",
new Object[]{fne.getMessage()});
} finally {
if (out != null) {
out.close();
}
if (filecontent != null) {
filecontent.close();
}
if (writer != null) {
writer.close();
}
}
}private String getFileName(final Part part) {
final String partHeader = part.getHeader("content-disposition");
LOGGER.log(Level.INFO, "Part Header = {0}", partHeader);
for (String content : part.getHeader("content-disposition").split(";")) {
if (content.trim().startsWith("filename")) {
return content.substring(
content.indexOf(‘=‘) + 1).trim().replace("\"", "");
}
}
return null;
}
protected void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
processRequest(request, response);
}
