1.使用JAR
jsp文件上传主要使用了两个jar包，commons-fileupload-1.2.1.jar和commons-io-1.4.jar
2.代码实现
public class UploadServlet extends HttpServlet {
/**
*
*/
private static final long serialVersionUID = 1L;
private ServletContext sc;
private String savePath;
@Override
protected void doGet(HttpServletRequest request,
HttpServletResponse response) throws ServletException, IOException {
doPost(request, response);
}
@Override
protected void doPost(HttpServletRequest request,
HttpServletResponse response) throws ServletException, IOException {
System.out.println("请求进来了..........");
// 设置请求的编码
request.setCharacterEncoding("UTF-8");
DiskFileItemFactory factory = new DiskFileItemFactory();//创建一个磁盘文件工厂
ServletFileUpload upload = new ServletFileUpload(factory);
try {
List items = upload.parseRequest(request);
Iterator it = items.iterator();
while (it.hasNext()) {
FileItem item = (FileItem) it.next();
if (item.isFormField()) {
System.out.println("表单的参数名称：" + item.getFieldName()
+ ",对应的参数值：" + item.getString("UTF-8"));
} else {
// 获取文件扩展名
String strtype = item.getName().substring(
item.getName().length() - 3,
item.getName().length());
strtype = strtype.toLowerCase();
if (strtype == "jpg" || strtype == "gif"
|| strtype == "txt") {
if (item.getName() != null
&& !item.getName().equals("")) {
System.out.println("上传文件的大小：" + item.getSize());
System.out.println("上传文件的类型："
+ item.getContentType());
System.out.println("上传文件的名称：" + item.getName());
System.out.println("文件的扩展名" + strtype);
File tempFile = new File(item.getName());
File file = new File(
sc.getRealPath("/") + savePath, tempFile
.getName());
item.write(file);
request.setAttribute("upload.message", "上传文件成功！");
} else {
request.setAttribute("upload.message",
"没有选择上传文件获取格式不支持");
}
} else {
request.setAttribute("upload.message", "上传文件格式不支持");
}
}
}
} catch (Exception e) {
e.printStackTrace();
request.setAttribute("upload.message", "上传文件不成功！");
}
// 转发
request.getRequestDispatcher("/uploadResult.jsp").forward(request,
response);
}
@Override
public void init(ServletConfig config) throws ServletException {
savePath = config.getInitParameter("savePath");
sc = config.getServletContext();
}