This article mainly introduces the function of Java Struts to upload pictures to a specified folder and display pictures. Friends who need it can refer to it
Following the last use of Servlet to upload pictures, this time MVC-based Struts is used The framework encapsulates Servlets and simplifies JSP page jumps.
JSP upload page
Upload must add enctype="multipart/form-data"
to the form, indicating that the submitted data is binary The
and must be method="post"
<%@ page language="java" contentType="text/html; charset=utf-8" pageEncoding="utf-8"%> <%@taglib prefix="s" uri="/struts-tags"%> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8"> </head> <body> <s:form action="login" method="post" enctype="multipart/form-data"> <s:file name="img" label="头像" /> <s:submit value="上传" /> </s:form> <!-- <form action="login" method="post" enctype="multipart/form-data"> 头像:<input type="file" name="img"></input> <input type="submit" values="上传"></input> </form> --> </body> </html>
struts.xml configuration (maven project is placed in resources)
<?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.multipart.maxSize" value="20480000"/> 设置文件上传最大值 <package name="struts2" extends="struts-default"> <action name="login" class="com.controller.TestStruts" method="logintest"> <result name="fail">/fail.jsp</result> <result name="success">/success.jsp</result> </action> </package> </struts>
TestStruts.java control class
Be sure to provide three attributes
File img; String imgFileName; String imgContentType;
Then for this 3 properties provide getter setter methods
package com.controller; import java.io.File; import java.io.IOException; import java.util.Map; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import org.apache.commons.io.FileUtils; import org.apache.struts2.ServletActionContext; import com.opensymphony.xwork2.ActionContext; import com.opensymphony.xwork2.ActionSupport; public class TestStruts extends ActionSupport{ private File img; private String imgFileName; private String imgContentType; public File getImg(){ return img; } public String getimgFileName(){ return imgFileName; } public String getImgContentType(){ return imgContentType; } public void setImg(File img){ this.img = img; } public void setImgFileName(String imgFileName){ this.imgFileName = imgFileName; } public void setImgFileContentType(String imgContentType){ this.imgContentType = imgContentType; } @SuppressWarnings("unchecked") public String logintest() throws IOException{ Map p = ActionContext.getContext().getSession(); p.put("imgFileName", imgFileName); File f = new File("D://imagebystruts"); if (!f.exists()) { f.mkdir(); } FileUtils.copyFile(img, new File(f, imgFileName)); return "success"; } }
The server.xml file in Tomcat configures the virtual path
<Context docBase="D:/imagebystruts" path="/imagebystruts" reloadable="true"/> <Context docBase="SSHTest" path="/SSHTest" reloadable="true" source="org.eclipse.jst.j2ee.server:SSHTest"/></Host>
success. jsp display picture
<%@ page language="java" contentType="text/html; charset=utf-8" pageEncoding="utf-8"%> <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <%@ taglib prefix="s" uri="/struts-tags" %> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8"> <title>success</title> </head> <body> <h1>成功</h1> <body> <img src="/imagebystruts/${imgFileName}"> </body> </body> </html>
Summary
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