struts 2 框架为处理文件上传提供了内置支持，它使用[在 html 中基于表单的文件上传]。当上传一个文件时，它通常会被存储在一个临时目录中，而且它们应该由 action 类进行处理或移动到一个永久的目录，用来确保数据不丢失。服务器在恰当的位置可能有一个安全策略，它会禁止你写到除了临时目录以外的目录，而且这个目录属于你的web应用应用程序。
通过预定义的名为文件上传的拦截器，struts 的文件上传是可能的，这个拦截器在 org.apache.struts2.interceptor.fileuploadinterceptor 类是可用的，而且是 defaultstack 的一部分。
创建视图文件
让我们开始创建需要浏览和上传选定的文件的视图。因此，让我们创建一个带有简单的 html 上传表单的 index.jsp，它允许用户上传文件：（表单的编码类型设置为multipart/form-data）
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 |
<%-- created by intellij idea. user: yzjxiaoyue date: 2017 / 7 / 28 time: 19 : 11 to change this template use file | settings | file templates. --%> <%@ page language= "java" contenttype= "text/html; charset=utf-8" pageencoding= "utf-8" %> <%@ taglib prefix= "s" uri= "/struts-tags" %> <!doctype html public "-//w3c//dtd html 4.01 transitional//en" "http://www.w3.org/tr/html4/loose.dtd" > <html> <head> <title>file upload</title> </head> <body> <form action= "upload" method= "post" enctype= "multipart/form-data" > <label for = "myfile" >upload your file</label> <input type= "file" name= "myfile" id= "myfile" /> <input type= "submit" value= "upload" /> </form> </body> </html> |
之后创建success.jsp页面：
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 |
<%-- created by intellij idea. user: yzjxiaoyue date: 2017 / 7 / 28 time: 19 : 14 to change this template use file | settings | file templates. --%> <%@ page contenttype= "text/html; charset=utf-8" %> <%@ taglib prefix= "s" uri= "/struts-tags" %> <html> <head> <title>file upload success</title> </head> <body> you have successfully uploaded <s:property value= "myfilefilename" /> </body> </html> |
创建error.jsp页面
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 |
<%-- created by intellij idea. user: yzjxiaoyue date: 2017 / 7 / 28 time: 20 : 05 to change this template use file | settings | file templates. --%> <%@ page contenttype= "text/html; charset=utf-8" %> <%@ taglib prefix= "s" uri= "/struts-tags" %> <html> <head> <title>file upload error</title> </head> <body> there has been an error in uploading the file. </body> </html> |
创建 action 类
接下来让我们创建一个称为 uploadfile.java 的 java 类，它负责上传文件，并且把这个文件存储在一个安全的位置：
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 |
package com.action;
import com.opensymphony.xwork2.actionsupport; import org.apache.commons.io.fileutils;
import java.io.file; import java.io.ioexception; public class uploadfile extends actionsupport{ private file myfile;
public file getmyfile() { return myfile; } public void setmyfile(file myfile) { this .myfile = myfile; }
private string myfilecontenttype;
private string myfilefilename;
private string destpath;
public string execute() { /* copy file to a safe location */ destpath = "e:\\program files\\apache-tomcat-9.0.0\\apache-tomcat-9.0.0.m22\\work\\" ; try { system.out.println( "src file name: " + myfile); system.out.println( "dst file name: " + myfilefilename); file destfile = new file(destpath, myfilefilename); fileutils.copyfile(myfile, destfile); } catch (ioexception e){ e.printstacktrace(); return error; } return success; }
public string getmyfilecontenttype() { return myfilecontenttype; } public void setmyfilecontenttype(string myfilecontenttype) { this .myfilecontenttype = myfilecontenttype; } public string getmyfilefilename() { return myfilefilename; } public void setmyfilefilename(string myfilefilename) { this .myfilefilename = myfilefilename; } } |
配置文件
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 |
<?xml version= "1.0" encoding= "utf-8" ?>
<!doctype struts public "-//apache software foundation//dtd struts configuration 2.3//en" "http://struts.apache.org/dtds/struts-2.3.dtd" >
<struts> <constant name= "struts.devmode" value= "true" /> <constant name= "struts.multipart.maxsize" value= "10000000" />
<constant name= "struts.multipart.savedir" value= "/tmp" /> <constant name= "struts.custom.i18n.resources" value= "struts" ></constant> < package name= "default" namespace= "/" extends = "struts-default" > <action name= "upload" class = "com.action.uploadfile" > <!--<interceptor-ref name= "basicstack" />--> <interceptor-ref name= "defaultstack" /> <interceptor-ref name= "fileupload" > <param name= "allowedtypes" >image/jpeg,image/jpg,image/gif</param> </interceptor-ref> <result name= "success" >/success.jsp</result> <result name= "error" >/error.jsp</result> </action> </ package > </struts> |
界面截图
以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持。
原文链接：https://blog.csdn.net/yzj_xiaoyue/article/details/76284279
查看更多关于Java框架Struts2实现图片上传功能的详细内容...