Question

我刚学会了将file上传到文件夹的地方。我也遵循了该教程，它也在工作。

当我提供路径C:\MyFile时，它正在上传我的文件。

我正在使用Eclipse IDE，现在我在项目中创建了一个名为files的文件夹。不幸的是，它没有上传，你可以看到一个截图我在哪里创建了一个文件夹来上传我的文件。

enter image description here

它不起作用你能帮助我吗？

我收到错误：

File not uploaded

以下是UploadFile.java的源代码：

package com.fileupload;

import java.io.File;
import java.io.IOException;
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.catalina.ha.backend.Sender;
import org.apache.commons.fileupload.FileItem;
import org.apache.commons.fileupload.FileItemFactory;
import org.apache.commons.fileupload.disk.DiskFileItemFactory;
import org.apache.commons.fileupload.servlet.ServletFileUpload;

public class UploadFile extends HttpServlet {
    private static final long serialVersionUID = 1L;
    private final String UPLOAD_DIRECTORY = "files/";

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

    // process only if its multipart content
    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<FileItem> multiparts = upload.parseRequest(request);

            for (FileItem item : multiparts) {
                if (!item.isFormField()) {
                    String name = new File(item.getName()).getName();
                    item.write(new File(UPLOAD_DIRECTORY + File.separator + name));
                }
            }
        } 
        catch (Exception e) 
        {
            System.out.println("File not uploaded");
        }
    }
}
}

这是我的index.jsp：

<!DOCTYPE html>
<html>
<head>
<title>Ajax File Upload with Progress Bar</title>
<!-- Include jQuery form & jQuery script file. -->
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.8/jquery.js" ></script>
<script src="http://malsup.github.com/jquery.form.js" ></script>
<script src="js/fileUploadScript.js" ></script>
<!-- Include css styles here -->
<link href="css/style.css" rel="stylesheet" type="text/css" />
</head>
<body>
    <h3>Ajax File Upload with Progress Bar</h3>
    <form id="UploadForm" action="UploadFile" method="post"
        enctype="multipart/form-data">
        <input type="file" size="60" id="myfile" name="myfile"> <input
            type="submit" value="Ajax File Upload">

        <div id="progressbox">
            <div id="progressbar"></div>
            <div id="percent">0%</div>
        </div>
        <br />

        <div id="message"></div>
    </form>
</body>
</html>

记住

当我将路径UPLOAD_DIRECTORY作为C:\Files时。然后它正在工作..但是当我在我的eclipse项目中创建一个文件夹时（见上面我的截图）..它说的是File not uploaded ..

EDITED !!

现在我正在使用：

private final String UPLOAD_DIRECTORY =getServletContext().getRealPath("/files/");

但是得到错误：

SEVERE: Allocate exception for servlet UploadFile
java.lang.NullPointerException
    at javax.servlet.GenericServlet.getServletContext(GenericServlet.java:125)
    at com.fileupload.UploadFile.<init>(UploadFile.java:20)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
    at java.lang.reflect.Constructor.newInstance(Unknown Source)
    at java.lang.Class.newInstance(Unknown Source)
    at org.apache.catalina.core.DefaultInstanceManager.newInstance(DefaultInstanceManager.java:154)
    at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:1099)
    at org.apache.catalina.core.StandardWrapper.allocate(StandardWrapper.java:830)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:137)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:107)
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:504)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:155)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:76)
    at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:934)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:90)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:515)
    at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1012)
    at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:642)
    at org.apache.coyote.http11.Http11NioProtocol$Http11ConnectionHandler.process(Http11NioProtocol.java:223)
    at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1597)
    at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1555)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
    at java.lang.Thread.run(Unknown Source)

当然，帮助将不胜感激!!

Answer 1

使用以下代码获取目录的真实路径：

getServletContext().getRealPath("/files/");

有关此方法的详细信息，请参阅BalusC's answer。

如果您使用init()方法调用此方法，请在init方法的第一行（推荐）或使用以下代码调用super.init(config);：

config.getServletContext().getRealPath("/files/");

文件未在特定目的地上传？

1 个答案: