<s:form action="fileupload" enctype="multipart/form-data">        <s:textfield label="照片描述" name="desc"></s:textfield>        <s:file label="文件1" name="file1"></s:file>        <s:submit value="上传"></s:submit>    </s:form>

    <s:url var="temp1" action="filedownload" ></s:url>    <s:a href="%{temp1}" >下载bload.png</s:a>

<struts>    <constant name="struts.enable.DynamicMethodInvocation" value="true" />    <constant name="struts.devMode" value="true" />    <constant name="struts.configuration.xml.reload" value="true" />    <constant name="struts.custom.i18n.resources" value="messageResource" />    <package name="p1" namespace="/" extends="struts-default">        <action name="fileupload" class="org.ah.s2.C1" method="fileupload">            <!-- 上传需要(自带)拦截器，传入参数 -->            <interceptor-ref name="fileUpload">                <!-- 定义允许上传的类型 -->                <param name="allowedTypes">image/jpeg,image/png</param>                <!-- 文件大小，单位：byte，不能用乘法计算，只能写最终数字 -->                <!-- 35k -->                <param name="maximumSize">35850</param>            </interceptor-ref>            <interceptor-ref name="defaultStack" />            <result name="success" type="dispatcher">                /ud_download.jsp            </result>            <!-- 文件被过滤掉，将返回input -->            <result name="input">/ud_upload.jsp</result>        </action>

        <action name="filedownload" class="org.ah.s2.C1" method="filedownload">            <!-- 只有一个result子元素，不用name -->            <result type="stream">                <param name="contentType">image/png</param>                <!-- fileName对应下载后的文件名，这里就用Action中的变量了 -->                <param name="contentDisposition">attachment;fileName=${downLoadAh}</param>                <param name="inputName">inputStream</param>            </result>        </action>    </package></struts>

package org.ah.s2;import java.io.File;import java.io.FileInputStream;import java.io.FileNotFoundException;import java.io.FileOutputStream;import java.io.IOException;import java.io.InputStream;import com.opensymphony.xwork2.Action;import com.opensymphony.xwork2.ActionSupport;public class C1 extends ActionSupport {    private String desc;// 描述    private File file1;// 上传文件。java.io    // 以下变量直接可得，文件名file1+固定后缀,都需要getter setter方法    private String file1FileName;// 上传文件名    private String file1ContentType;// 上传文件类型    public String getDesc() {        return desc;    }    public void setDesc(String desc) {        this.desc = desc;    }    public File getFile1() {        return file1;    }    public void setFile1(File file1) {        this.file1 = file1;    }    public String getFile1FileName() {        return file1FileName;    }    public void setFile1FileName(String file1FileName) {        this.file1FileName = file1FileName;    }    public String getFile1ContentType() {        return file1ContentType;    }    public void setFile1ContentType(String file1ContentType) {        this.file1ContentType = file1ContentType;    }    /**     * 文件上传     *      * @return     * @throws IOException     */    public String fileupload() throws IOException {        // \t：制表符        System.out.println("File name:" + this.file1FileName + "\t"                + "ContentType:" + this.file1ContentType + "\t" + "描述："                + this.desc);        // 文件拷贝        FileInputStream fis = new FileInputStream(this.file1);        FileOutputStream fos = new FileOutputStream("D:\\fileupload\\"                + this.file1FileName);        byte[] bs = new byte[1024];        int real = fis.read(bs);        while (real > 0) {            fos.write(bs, 0, real);            real = fis.read(bs);        }        fos.close();        fis.close();        return Action.SUCCESS;    }    // --------------------------------------------------    // 下载时默认名称，只需getter方法即可    private String downLoadAh;    public String getDownLoadAh() {        return downLoadAh;    }    /**     * 文件下载     * @return     */    public String filedownload() {        downLoadAh = "border_1.png";        return Action.SUCCESS;    }    // 用于下载的文件输入流
　　 // 对应：<param name="inputName">inputStream</param>
    public InputStream getInputStream() {        FileInputStream fis = null;        try {            fis = new FileInputStream(new File("D:\\fileupload\\"                    + downLoadAh));        } catch (FileNotFoundException e) {            e.printStackTrace();        }        return fis;    }}

struts.messages.error.file.too.large=\u6587\u4EF6\u592A\u5927struts.messages.error.file.extension.not.allowed=\u6587\u4EF6\u7C7B\u578B\u4E0D\u5339\u914Dstruts.messages.error.content.type.not.allowed=\u4E0A\u4F20\u7C7B\u578B\u4E0D\u6B63\u786E