Question

我正在尝试使用servlet / jsp在我的服务器上的文件夹上传一些图像。

下面是我的代码，它在我的本地机器上运行：

 import java.io.*;
 import java.util.*;

 import javax.servlet.ServletConfig;
 import javax.servlet.ServletException;
  import javax.servlet.http.HttpServlet;
  import javax.servlet.http.HttpServletRequest;
  import javax.servlet.http.HttpServletResponse;

   import org.apache.commons.fileupload.FileItem;
    import org.apache.commons.fileupload.FileUploadException;
   import org.apache.commons.fileupload.disk.DiskFileItemFactory;
   import org.apache.commons.fileupload.servlet.ServletFileUpload;
     import org.apache.commons.io.output.*;

      public class UploadServlet extends HttpServlet {

  private boolean isMultipart;
   private String filePath;
  private int maxFileSize = 1000 * 1024;
   private int maxMemSize = 1000 * 1024;
   private File file ;

    public void init( ){
  // Get the file location where it would be stored.
  filePath = 
         getServletContext().getInitParameter("file-upload"); 
   }
    public void doPost(HttpServletRequest request, 
           HttpServletResponse response)
          throws ServletException, java.io.IOException {
  // Check that we have a file upload request
     isMultipart = ServletFileUpload.isMultipartContent(request);
     response.setContentType("text/html");
     java.io.PrintWriter out = response.getWriter( );
      if( !isMultipart ){
     out.println("<html>");
     out.println("<head>");
     out.println("<title>Servlet upload</title>");  
     out.println("</head>");
     out.println("<body>");
     out.println("<p>No file uploaded</p>"); 
     out.println("</body>");
     out.println("</html>");
     return;
     }
     DiskFileItemFactory factory = new DiskFileItemFactory();
  // maximum size that will be stored in memory
     factory.setSizeThreshold(maxMemSize);
  // Location to save data that is larger than maxMemSize.
     factory.setRepository(new File(" C:/Users/puneet verma/Downloads/"));  

  // Create a new file upload handler
      ServletFileUpload upload = new ServletFileUpload(factory);
  // maximum file size to be uploaded.
     upload.setSizeMax( maxFileSize );

     try{ 
  // Parse the request to get file items.
     List fileItems = upload.parseRequest(request);

  // Process the uploaded file items
      Iterator i = fileItems.iterator();

     out.println("<html>");
     out.println("<head>");
     out.println("<title>Servlet upload</title>");  
     out.println("</head>");
     out.println("<body>");
     while ( i.hasNext () ) 
     {
       FileItem fi = (FileItem)i.next();
     if ( !fi.isFormField () )  
     {
        // Get the uploaded file parameters
        String fieldName = fi.getFieldName();
        String fileName = fi.getName();
        String contentType = fi.getContentType();
        boolean isInMemory = fi.isInMemory();
        long sizeInBytes = fi.getSize();
        // Write the file
        if( fileName.lastIndexOf("\\") >= 0 ){
           file = new File( filePath + 
           fileName.substring( fileName.lastIndexOf("\\"))) ;
        }else{
           file = new File( filePath + 
           fileName.substring(fileName.lastIndexOf("\\")+1)) ;
        }
        fi.write( file ) ;
        out.println("Uploaded Filename: " + fileName + "<br>");
     }
      }
     out.println("</body>");
          out.println("</html>");
     }catch(Exception ex) {
     System.out.println(ex);
     }
       }
           public void doGet(HttpServletRequest request, 
                   HttpServletResponse response)
          throws ServletException, java.io.IOException {

           throw new ServletException("GET method used with " +
            getClass( ).getName( )+": POST method required.");
           } 
            }

现在我的jsp代码，我上传文件：

<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
pageEncoding="ISO-8859-1"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"   "http://www.w3.org/TR/html4/loose.dtd">
   <html>
  <head>
      <title>File Uploading Form</title>
     </head>
       <body>
        <h3>File Upload:</h3>
      Select a file to upload: <br />
       <form action="UploadServlet" method="post"
                    enctype="multipart/form-data">
      <input type="file" name="file" size="50" />
       <br />
    <input type="submit" value="Upload File" />
       </form>
      </body>
        </html>

在我的web.xml文件中，我包含了这样的路径：

      <context-param>
<description>Location to store uploaded file</description>
<param-name>file-upload</param-name>
<param-value>
    C:\Users\puneet verma\Downloads\
 </param-value>
     </context-param>

我已经使用了我的服务器路径http://grand-shopping.com/＆lt;“some folder”＆gt; ，但它根本不在这里工作。

我正在使用的库是：

公地文件上传-1.3.jar
公地-IO-2.2.jar

任何人都可以建议我，我需要如何定义我的服务器路径，才能成功上传图片。

Answer 1

以下代码正在我的实时服务器以及我自己的Lapy中工作。

注意：

请在WebContent中创建数据文件夹，并放入任何单个图片或任何文件（jsp或html文件）。

添加jar文件

公地集合-3.1.jar
公地文件上传-1.2.2.jar
公地IO-2.1.jar
共享记录-1.0.4.jar

<强> upload.jsp

<%@ page language="java" contentType="text/html; charset=ISO-8859-1" pageEncoding="ISO-8859-1"%> <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"> <title>File Upload</title> </head> <body> <form method="post" action="UploadServlet" enctype="multipart/form-data"> Select file to upload: <input type="file" name="dataFile" id="fileChooser"/><br/><br/> <input type="submit" value="Upload" /> </form> </body> </html>

<强> UploadServlet.java

package com.servlet; import java.io.File; import java.io.IOException; import java.util.Iterator; import java.util.List; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import org.apache.commons.fileupload.FileItem; import org.apache.commons.fileupload.FileUploadException; import org.apache.commons.fileupload.disk.DiskFileItemFactory; import org.apache.commons.fileupload.servlet.ServletFileUpload; /** * Servlet implementation class UploadServlet */ public class UploadServlet extends HttpServlet { private static final long serialVersionUID = 1L; private static final String DATA_DIRECTORY = "data"; private static final int MAX_MEMORY_SIZE = 1024 * 1024 * 2; private static final int MAX_REQUEST_SIZE = 1024 * 1024; protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { // Check that we have a file upload request boolean isMultipart = ServletFileUpload.isMultipartContent(request); if (!isMultipart) { return; } // Create a factory for disk-based file items DiskFileItemFactory factory = new DiskFileItemFactory(); // Sets the size threshold beyond which files are written directly to // disk. factory.setSizeThreshold(MAX_MEMORY_SIZE); // Sets the directory used to temporarily store files that are larger // than the configured size threshold. We use temporary directory for // java factory.setRepository(new File(System.getProperty("java.io.tmpdir"))); // constructs the folder where uploaded file will be stored String uploadFolder = getServletContext().getRealPath("") + File.separator + DATA_DIRECTORY; // Create a new file upload handler ServletFileUpload upload = new ServletFileUpload(factory); // Set overall request size constraint upload.setSizeMax(MAX_REQUEST_SIZE); try { // Parse the request List items = upload.parseRequest(request); Iterator iter = items.iterator(); while (iter.hasNext()) { FileItem item = (FileItem) iter.next(); if (!item.isFormField()) { String fileName = new File(item.getName()).getName(); String filePath = uploadFolder + File.separator + fileName; File uploadedFile = new File(filePath); System.out.println(filePath); // saves the file to upload directory item.write(uploadedFile); } } // displays done.jsp page after upload finished getServletContext().getRequestDispatcher("/done.jsp").forward( request, response); } catch (FileUploadException ex) { throw new ServletException(ex); } catch (Exception ex) { throw new ServletException(ex); } } }

<强>的web.xml

<servlet> <description></description> <display-name>UploadServlet</display-name> <servlet-name>UploadServlet</servlet-name> <servlet-class>com.servlet.UploadServlet</servlet-class> </servlet> <servlet-mapping> <servlet-name>UploadServlet</servlet-name> <url-pattern>/UploadServlet</url-pattern> </servlet-mapping>

<强> done.jsp

<%@ page language="java" contentType="text/html; charset=ISO-8859-1" pageEncoding="ISO-8859-1"%> <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"> <title>Upload Done</title> </head> <body> <h3>Your file has been uploaded!</h3> </body> </html>

Answer 2

public class FileUploadExample extends HttpServlet {
     protected void doPost(HttpServletRequest request, HttpServletResponse response)
                throws ServletException, IOException {
            boolean isMultipart = ServletFileUpload.isMultipartContent(request);

            if (isMultipart) {
                // Create a factory for disk-based file items
                FileItemFactory factory = new DiskFileItemFactory();

                // Create a new file upload handler
                ServletFileUpload upload = new ServletFileUpload(factory);

                try {
                    // Parse the request
                    List items = upload.parseRequest(request);
                    Iterator iterator = items.iterator();
                    while (iterator.hasNext()) {
                        FileItem item = (FileItem) iterator.next();
                        if (!item.isFormField()) {
                            String fileName = item.getName();    
                            String root = getServletContext().getRealPath("/");
                            File path = new File(root + "/uploads");
                            if (!path.exists()) {
                                boolean status = path.mkdirs();
                            }

                            File uploadedFile = new File(path + "/" + fileName);
                            System.out.println(uploadedFile.getAbsolutePath());
                            item.write(uploadedFile);
                        }
                    }
                } catch (FileUploadException e) {
                    e.printStackTrace();
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
        }

}

Answer 3

你无法像这样上传。

http://grand-shopping.com/<"some folder">

您需要一个与本地

完全相同的物理路径

C:/Users/puneet verma/Downloads/

您可以做的是创建服务器正在运行的本地路径。因此，您可以存储和检索文件。如果您从任何网站购买了某个域名，则会有上传文件的路径。您将这些变量创建为静态常量，并根据您正在使用的服务器（本地/网站）使用它。

Answer 4

您只能使用绝对路径 http://grand-shopping.com/＆lt;“某个文件夹”＆gt;不是绝对的道路。

您可以使用应用程序内部的路径，这是一个非常难以理解的路径或者您可以使用

中的服务器特定路径

windows -> C:/Users/puneet verma/Downloads/
linux -> /opt/Downloads/

Answer 5

我发现了类似的问题并找到了解决方案，我在博客上写了关于如何upload the file using JSP，在那个例子中我使用了绝对路径。请注意，如果您想要路由到其他基于URL的位置，您可以放置一个ESB，如WSO2 ESB

如何使用jsp上传服务器文件夹上的文件

5 个答案: