1.上传组件
①Apache的Commons FileUpload
②JavaZoom的UploadBean
③JspSmartUpload
2.下载Commons的FileUpload组件
同时还要下载Commons的IO组件
3.使用实例
步骤一：创建文件上传的页面：fileUpload.jsp
文件上传
上传人名:
上传文件:
步骤二：创建处理文件上传的servlet：fileUploadServlet
package com.yinger.servlet;
import java.io.File;
import java.io.IOException;
import java.util.Iterator;
import java.util.List;
import javax.servlet.ServletConfig;
import javax.servlet.ServletContext;
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.disk.DiskFileItemFactory;
import org.apache.commons.fileupload.servlet.ServletFileUpload;
public class FileUploadServlet extends HttpServlet {
private ServletContext sc;
private String savePath;
private static final long serialVersionUID = 151650843430214502L;
public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
doPost(request, response);
}
public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
request.setCharacterEncoding("UTF-8");
DiskFileItemFactory factory = new DiskFileItemFactory();
ServletFileUpload servletFileUpload = new ServletFileUpload(factory);//通过工厂生成一个处理文件上传的servlet对象
try {
List items = servletFileUpload.parseRequest(request);//解析request
Iterator iterator = items.iterator();
while (iterator.hasNext()) {
FileItem item = (FileItem) iterator.next();
if(item.isFormField()){//表单的参数字段
System.out.println("表单的参数名称："+item.getFieldName()+",表单的参数值："+item.getString("UTF-8"));
}else {
if(item.getName()!=null && !item.getName().equals("")){//一个上传的文件
System.out.println("文件的名称："+item.getName());
System.out.println("文件的大小："+item.getSize());
System.out.println("文件的类型："+item.getContentType());
File tempFile = new File(item.getName());//getName得到的文件名称包含了它在客户端的路径
File file = new File(sc.getRealPath("/")+savePath,tempFile.getName());
item.write(file);//将上传的文件写入到file中
request.setAttribute("message", "上传文件成功！");
}else{
request.setAttribute("message", "没有选择上传文件！");
}
}
}
} catch (Exception e) {
e.printStackTrace();
request.setAttribute("message", "上传文件失败！");
}
request.getRequestDispatcher("/fileUploadResult.jsp").forward(request, response);//转向，输出结果
}
@Override
public void init(ServletConfig config) throws ServletException {
savePath = config.getInitParameter("savePath");
sc = config.getServletContext();
}
}
步骤三：修改web.xml
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" version="2.5">
This is the description of my J2EE component
This is the display name of my J2EE component
FileUploadServlet
com.yinger.servlet.FileUploadServlet
savePath
uploads
FileUploadServlet
/servlet/FileUploadServlet
index.jsp
同时在项目的根目录下创建文件夹 uploads (可以就在WebRoot中创建)
步骤四：创建显示上传结果的页面：fileUploadResult.jsp
文件上传
${requestScope['message'] }
效果展示
