Java Struts图片上传至指定文件夹并显示图片

继上一次利用Servlet实现图片上传，这次利用基于MVC的Struts框架，封装了Servlet并简化了JSP页面跳转。

JSP上传页面

上传一定要为form加上enctype="multipart/form-data"，表示提交的数据时二进制的
并且必须是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配置(maven项目放在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控制类

一定要提供三个属性

File img;

String imgFileName;

String imgContentType;

然后为这3个属性提供getter setter方法

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";
    }
}

Tomcat中server.xml文件配置虚拟路径

<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显示图片

<%@ 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>