js上传文件 java后台接收文件

<div class="input-chunk">  
    <div>输入文件：</div>  
    <input type="file"value="选择文件"id="upload-file">  
    <br>  
    <a id="start-upload"href="javascript:void(0);"onclick="uploadFile();">开始上传</a>  
</div> 

functionuploadFile(){  
    var fileObj = document.getElementById("upload-file").files[0]; //获取文件对象  
    var FileController = "entityServlet1"; //接收上传文件的后台地址  
              
    if(fileObj){  
        alert(fileObj);  
         //FormData 对象  
             var form = newFormData();   
             form.append("file", fileObj);//文件对象     
      
             //XMLHttpRequest 对象  
             var xhr = newXMLHttpRequest();      
             xhr.open("post", FileController, true);      
             xhr.onload = function() {   
                 alert(xhr.responseText);     
             };   
             xhr.send(form);  
                  
    }else{  
        alert("未选择文件");  
    }  
}  

importjava.io.File;  
importjava.io.IOException;  
importjava.util.Iterator;  
importjava.util.List;  
  
importjavax.servlet.ServletException;  
importjavax.servlet.http.HttpServlet;  
importjavax.servlet.http.HttpServletRequest;  
importjavax.servlet.http.HttpServletResponse;  
  
importorg.apache.commons.fileupload.FileItem;  
importorg.apache.commons.fileupload.disk.DiskFileItemFactory;  
importorg.apache.commons.fileupload.servlet.ServletFileUpload;  
  
public class EntityServlet1 extendsHttpServlet {  
  
    private static final long serialVersionUID = 1L;  
    private String uploadPath = "D:\temp"; //上传文件的目录  
File tempPathFile;  
  
    //重写doPost方法，处理事件识别请求  
    protected voiddoPost(HttpServletRequest request,  
            HttpServletResponse response) throwsServletException, IOException {  
        try{  
            //Create a factory for disk-based file items  
            DiskFileItemFactory factory = newDiskFileItemFactory();  
  
            //Set factory constraints  
            factory.setSizeThreshold(4096); //设置缓冲区大小，这里是4kb  
            factory.setRepository(tempPathFile);//设置缓冲区目录  
  
            //Create a new file upload handler  
            ServletFileUpload upload = newServletFileUpload(factory);  
  
            //Set overall request size constraint  
            upload.setSizeMax(4194304); //设置最大文件尺寸，这里是4MB  
List<FileItem> items = upload.parseRequest(request);//得到所有的文件  
            Iterator<FileItem> i =items.iterator();  
            while(i.hasNext()) {  
                FileItem fi =(FileItem) i.next();  
                String fileName =fi.getName();  
                if (fileName != null) {  
                    File fullFile = new File(new String(fi.getName().getBytes(), "utf-8")); //解决文件名乱码问题  
                    File savedFile = newFile(uploadPath, fullFile.getName());  
                    fi.write(savedFile);  
                }  
            }  
            System.out.print("upload succeed");  
        } catch(Exception e) {  
  
        }  
    }  
}