Java 如何使用jsp上传服务器文件夹中的文件
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How to upload files on server folder using jsp
提问by puneetjava
I am trying to upload some images on folder which locates on my server using servlet/jsp.
我正在尝试使用 servlet/jsp 在位于我的服务器上的文件夹上上传一些图像。
Below is my code, which is working on my local machine:
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.");
}
}
Now my jsp code, where i upload file:
现在我的jsp代码，我上传文件的地方：
<%@ 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>
In My web.xml file, I've included path like this:
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>
I've used my server path http://grand-shopping.com/<"some folder"> , but it's not working here at all.
我已经使用了我的服务器路径http://grand-shopping.com/<"some folder"> ，但它在这里根本不起作用。
Libraries i'm using are:
我正在使用的库是：
- commons-fileupload-1.3.jar
- commons-io-2.2.jar
- commons-fileupload-1.3.jar
- commons-io-2.2.jar
Can anyone suggest me , how exactly i need to define my server path, in order to upload images successfully.
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像。
回答by Vinoth Krishnan
You cannot upload like this.
你不能像这样上传。
http://grand-shopping.com/<"some folder">
You need a physical path exactly like in your local
您需要与本地完全相同的物理路径
C:/Users/puneet verma/Downloads/
What you can do is create some local path where your server is working. Hence you can store and retrieve the file. If you bought some domain from any websites there will be path to upload the files. You create these variable as static constant and use it based on the server you are working (Local/Website).
您可以做的是创建一些您的服务器正在工作的本地路径。因此，您可以存储和检索文件。如果您从任何网站购买了一些域名，就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。
回答by Dev
You can only use absolute path http://grand-shopping.com/<"some folder"> is not an absolute path.
您只能使用绝对路径 http://grand-shopping.com/<"some folder"> 不是绝对路径。
Either you can use a path inside the application which is vurneable or you can use server specific path like in
您可以在应用程序中使用易受攻击的路径，也可以使用服务器特定的路径，如
windows -> C:/Users/puneet verma/Downloads/
linux -> /opt/Downloads/
回答by Vishal Shah
Below code is working on my live server as well as in my own Lapy.
下面的代码适用于我的实时服务器以及我自己的 Lapy。
Note:
笔记：
Please Create datafolder in WebContent and put in any single image or any file(jsp or html file).
请在 WebContent 中创建数据文件夹并放入任何单个图像或任何文件（jsp 或 html 文件）。
Add jar files
添加jar文件
commons-collections-3.1.jar
commons-fileupload-1.2.2.jar
commons-io-2.1.jar
commons-logging-1.0.4.jar
commons-collections-3.1.jar
commons-fileupload-1.2.2.jar
commons-io-2.1.jar
commons-logging-1.0.4.jar
upload.jsp
上传.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>
UploadServlet.java
上传Servlet.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);
}
}
}
web.xml
网页.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>
done.jsp
完成.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>
回答by Vanji
I found the similar problem and found the solution and i have blogged about how to upload the file using JSP, In that example i have used the absolute path. Note that if you want to route to some other URL based location you can put a ESB like WSO2 ESB
我发现了类似的问题并找到了解决方案，并且我在博客中介绍了如何使用 JSP 上传文件，在该示例中我使用了绝对路径。请注意，如果您想路由到其他一些基于 URL 的位置，您可以放置一个像WSO2 ESB这样的ESB
回答by Vicky
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();
}
}
}
}
