上传图片或文件

public void upload(HttpServletRequest request, HttpServletResponse response)
throws Exception {
String name = "";
String uploadUrl = "/upload/game/";
String uploadPath = request.getSession().getServletContext()
.getRealPath(uploadUrl) + "\\"; // 用于存放上传文件的目录
String tempPath = request.getSession().getServletContext().getRealPath("/upload/temp"); // 用于存放临时文件的目录
boolean isMultipart = FileUpload.isMultipartContent(request);// 检查是否是一个文件上传请求

if (!isMultipart) {
throw new Exception("不是一个文件上传的请求");
}
DiskFileItemFactory factory = new DiskFileItemFactory();
factory.setSizeThreshold(4096);// 设置最多只允许在内存中存储的数据
factory.setRepository(new File(tempPath));// (缓存)

// Create a new file upload handler
FileUpload upload = new FileUpload(factory);
// Set overall request size constraint设置允许用户上传文件大小
upload.setSizeMax(1263509131 * 1024);

List items = upload.parseRequest(request);// 读取上传信息
Iterator iter = items.iterator();
String suffix = "";//后缀名
while (iter.hasNext()) {
FileItem item = (FileItem) iter.next();
String fileUrl = "";//需要保存的文件路径，

// 忽略其他不是文件域的所有表单信息
if (!item.isFormField()) {
name = item.getName();
name = name.substring(name.lastIndexOf(File.separator) + 1,
name.length());

long size = item.getSize();
if (!((name == null || name.equals("")) && size == 0)) {
suffix = name.substring(name.lastIndexOf("."),name.length());
name= Util.renameFileNamStr() + suffix;//自己写的重命名规则(用年月日)
if (!validate(uploadUrl + name)) {// 验证图片或文件是否已存在
throw new Exception("文件已存在");
}
item.write(new File(uploadPath + name));// 这里的路径你可以改成你感兴趣的地方
fileUrl = uploadUrl + name;
}
parameters.put(item.getFieldName(), fileUrl);// 有值则存入map
} else {
String fieldName = item.getFieldName();
String value;

try {
value = item.getString("UTF-8");
parameters.put(fieldName, value);
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
return;
}
}
}
}