實現文件上傳功能（FileUpload組件）

時間 2020-06-20

標籤實現文件上傳功能 fileupload 組件简体版

原文原文鏈接

文件上傳：java

項目中常常用到文件上傳。apache

本身實現文件上傳，使用文件上傳組件fileupload組件eclipse

一、指定表單類型爲文件上傳，jsp

enctype=」multipart/form-data」post

二、提交方式必須是：postspa

三、表單中存在文件域元素。code

須要的jar包orm

index.jsp對象

<body>
    <form action="${pageContext.request.contextPath}/FileUploadTest" method = "post" enctype="multipart/form-data"> 用戶名：:<input type = "text" name = "username"/><br> 文件:<input type = "file" name = "file1"/><br>
        <input type = "submit">
    </form>
</body>

FileUploadTest.servlet

package zck.servlet; import java.io.File; import java.io.IOException; import java.io.InputStream; import java.util.List; import javax.servlet.ServletException; import javax.servlet.annotation.WebServlet; 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.FileItemFactory; import org.apache.commons.fileupload.FileUploadException; import org.apache.commons.fileupload.disk.DiskFileItemFactory; import org.apache.commons.fileupload.servlet.ServletFileUpload; /** * Servlet implementation class FileUploadTest */ @WebServlet("/FileUploadTest") public class FileUploadTest extends HttpServlet { private static final long serialVersionUID = 1L; /** * @see HttpServlet#HttpServlet() */
    public FileUploadTest() { super(); // TODO Auto-generated constructor stub
 } /** * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response) */
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { //建立文件上傳工廠類
        DiskFileItemFactory fileItemFactory  =  new DiskFileItemFactory(); //建立文件上傳核心類
        ServletFileUpload upload = new ServletFileUpload(fileItemFactory); upload.setFileSizeMax(30*1024*1024);//設置單個文件最大值30M
        upload.setSizeMax(50*1024*1024);//最多50個文件 //判斷表單是不是文件上傳表單
            if(upload.isMultipartContent(request)) { //把請求數據轉化爲FileItem對象集合
                try { List<FileItem> list = upload.parseRequest(request); //遍歷獲得每個數據項
                    for(FileItem fileItem :list) { //判斷普通項，仍是文件。
                        if(fileItem.isFormField()) { //普通表單項
                            String fieldName =fileItem.getFieldName();//表單元素名稱
                            String content =fileItem.getString();//值
                            System.out.print(fieldName+"\n"+content+"\n\n"); }else { //文件上傳表單項 
                            String name =fileItem.getName();//獲取文件名 //上傳文件目錄路徑
                            String basePath = ("D:\\software\\eclipse\\workplace2019-1\\UploadFiles\\WebContent\\upload\\"); //新建文件
                            File file = new File(basePath,name); fileItem.write(file); fileItem.delete();//刪除臨時文件
 } } } catch (FileUploadException e) { // TODO Auto-generated catch block
 e.printStackTrace(); } catch (Exception e) { // TODO Auto-generated catch block
 e.printStackTrace(); } }else { System.out.print("不是文件上傳表單，不處理"); } } /** * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response) */
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { // TODO Auto-generated method stub
 doGet(request, response); } }