struts2单个文件上传的两种实现方式

通过2种方式模拟单个文件上传，效果如下所示

开发步骤如下：

1、新建一个web工程，导入struts2上传文件所需jar，如下图

目录结构

2、新建Action

第一种方式

代码如下:

package com.ljq.action;

import java.io.File;

import org.apache.commons.io.FileUtils;
import org.apache.struts2.ServletActionContext;

import com.opensymphony.xwork2.ActionContext;
import com.opensymphony.xwork2.ActionSupport;

@SuppressWarnings("serial")
public class UploadAction extends ActionSupport{

private File image; //上传的文件
    private String imageFileName; //文件名称
    private String imageContentType; //文件类型

public String execute() throws Exception {
        String realpath = ServletActionContext.getServletContext().getRealPath("/images");
        //D:\apache-tomcat-6.0.18\webapps\struts2_upload\images
        System.out.println("realpath: "+realpath);
        if (image != null) {
            File savefile = new File(new File(realpath), imageFileName);
            if (!savefile.getParentFile().exists())
                savefile.getParentFile().mkdirs();
            FileUtils.copyFile(image, savefile);
            ActionContext.getContext().put("message", "文件上传成功");
        }
        return "success";
    }

public File getImage() {
        return image;
    }

public void setImage(File image) {
        this.image = image;
    }

public String getImageFileName() {
        return imageFileName;
    }

public void setImageFileName(String imageFileName) {
        this.imageFileName = imageFileName;
    }

public String getImageContentType() {
        return imageContentType;
    }

public void setImageContentType(String imageContentType) {
        this.imageContentType = imageContentType;
    }

}

第二种方式

代码如下:

package com.ljq.action;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;

import org.apache.struts2.ServletActionContext;

import com.opensymphony.xwork2.ActionSupport;

@SuppressWarnings("serial")
public class UploadAction2 extends ActionSupport {

// 封装上传文件域的属性
    private File image;
    // 封装上传文件类型的属性
    private String imageContentType;
    // 封装上传文件名的属性
    private String imageFileName;
    // 接受依赖注入的属性
    private String savePath;

@Override
    public String execute() {
        FileOutputStream fos = null;
        FileInputStream fis = null;
        try {
            // 建立文件输出流
            System.out.println(getSavePath());
            fos = new FileOutputStream(getSavePath() + "\\" + getImageFileName());
            // 建立文件上传流
            fis = new FileInputStream(getImage());
            byte[] buffer = new byte[1024];
            int len = 0;
            while ((len = fis.read(buffer)) > 0) {
                fos.write(buffer, 0, len);
            }
        } catch (Exception e) {
            System.out.println("文件上传失败");
            e.printStackTrace();
        } finally {
            close(fos, fis);
        }
        return SUCCESS;
    }

/**
     * 返回上传文件的保存位置
     *
     * @return
     */
    public String getSavePath() throws Exception{
        return ServletActionContext.getServletContext().getRealPath(savePath);
    }

public void setSavePath(String savePath) {
        this.savePath = savePath;
    }

public File getImage() {
        return image;
    }

public void setImage(File image) {
        this.image = image;
    }

public String getImageContentType() {
        return imageContentType;
    }

public void setImageContentType(String imageContentType) {
        this.imageContentType = imageContentType;
    }

public String getImageFileName() {
        return imageFileName;
    }

public void setImageFileName(String imageFileName) {
        this.imageFileName = imageFileName;
    }

private void close(FileOutputStream fos, FileInputStream fis) {
        if (fis != null) {
            try {
                fis.close();
            } catch (IOException e) {
                System.out.println("FileInputStream关闭失败");
                e.printStackTrace();
            }
        }
        if (fos != null) {
            try {
                fos.close();
            } catch (IOException e) {
                System.out.println("FileOutputStream关闭失败");
                e.printStackTrace();
            }
        }
    }

}

struts.xml配置文件

代码如下:

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE struts PUBLIC
    "-//Apache Software Foundation//DTD Struts Configuration 2.0//EN"
    "http://struts.apache.org/dtds/struts-2.0.dtd">

<struts>
    <!-- 该属性指定需要Struts2处理的请求后缀，该属性的默认值是action，即所有匹配*.action的请求都由Struts2处理。
        如果用户需要指定多个请求后缀，则多个后缀之间以英文逗号（,）隔开。 -->
    <constant name="struts.action.extension" value="do" />
    <!-- 设置浏览器是否缓存静态内容,默认值为true(生产环境下使用),开发阶段最好关闭 -->
    <constant name="struts.serve.static.browserCache" value="false" />
    <!-- 当struts的配置文件修改后,系统是否自动重新加载该文件,默认值为false(生产环境下使用),开发阶段最好打开 -->
    <constant name="struts.configuration.xml.reload" value="true" />
    <!-- 开发模式下使用,这样可以打印出更详细的错误信息 -->
    <constant name="struts.devMode" value="true" />
    <!-- 默认的视图主题 -->
    <constant name="struts.ui.theme" value="simple" />
    <!--<constant name="struts.objectFactory" value="spring" />-->
    <!--解决乱码    -->
    <constant name="struts.i18n.encoding" value="UTF-8" />
    <!-- 指定允许上传的文件最大字节数。默认值是2097152(2M) -->
    <constant name="struts.multipart.maxSize" value="10701096"/>
    <!-- 设置上传文件的临时文件夹,默认使用javax.servlet.context.tempdir -->
    <constant name="struts.multipart.saveDir " value="d:/tmp" />

<package name="upload" namespace="/upload" extends="struts-default">
        <action name="*_upload" class="com.ljq.action.UploadAction" method="{1}">
            <result name="success">/WEB-INF/page/message.jsp</result>
        </action>
    </package>

<package name="upload2" extends="struts-default">
        <action name="upload2" class="com.ljq.action.UploadAction2" method="execute">
            <!-- 动态设置savePath的属性值 -->
            <param name="savePath">/images</param>
            <result name="success">/WEB-INF/page/message.jsp</result>
            <result name="input">/upload/upload.jsp</result>
            <interceptor-ref name="fileUpload">
                <!-- 文件过滤 -->
                <param name="allowedTypes">image/bmp,image/png,image/gif,image/jpeg</param>
                <!-- 文件大小, 以字节为单位 -->
                <param name="maximumSize">1025956</param>
            </interceptor-ref>
            <!-- 默认拦截器必须放在fileUpload之后，否则无效 -->
            <interceptor-ref name="defaultStack" />
        </action>
    </package>
</struts>

上传表单页面

代码如下:

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%@taglib uri="/struts-tags" prefix="s" %>

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
    <head>
        <title>文件上传</title>

<meta http-equiv="pragma" content="no-cache">
        <meta http-equiv="cache-control" content="no-cache">
        <meta http-equiv="expires" content="0">
    </head>

<body>
        <!-- ${pageContext.request.contextPath}/upload/execute_upload.do -->
        <!-- ${pageContext.request.contextPath}/upload2/upload2.do -->
        <form action="${pageContext.request.contextPath}/upload2/upload2.do"
              enctype="multipart/form-data" method="post">
            文件:<input type="file" name="image">
                <input type="submit" value="上传" />
        </form>
        <br/>
        <s:fielderror />
    </body>
</html>

显示结果页面

代码如下:

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%@ taglib uri="/struts-tags" prefix="s"%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
  <head>

<title>上传成功</title>

<meta http-equiv="pragma" content="no-cache">
    <meta http-equiv="cache-control" content="no-cache">
    <meta http-equiv="expires" content="0">   
  </head>

<body>
    上传成功！
    <br/><br/>
    <!-- ${pageContext.request.contextPath} tomcat部署路径，
          如：D:\apache-tomcat-6.0.18\webapps\struts2_upload\ -->
    <img src="${pageContext.request.contextPath}/<s:property value="'images/'+imageFileName"/>">
    <s:debug></s:debug>
  </body>
</html>