Struts的文件下载功能实现代码

package com.tengfeiyang.action;

import java.io.File;
import java.io.FileInputStream;
import java.io.InputStream;

import com.opensymphony.xwork2.ActionSupport;

/**
 * @author yangtf
 *　　文件下载 16/02/23
 */
public class FileDownloadAction extends ActionSupport{

    /**
     * 
     */
    private static final long serialVersionUID = 1L;
    
    private String fileName;
    
    public String getFileName() {
        return fileName;
    }

    public void setFileName(String fileName) {
        this.fileName = fileName;
    }

    public InputStream getDownloadFile()throws Exception{
        String path;
        if ("Java".equals(fileName)) {
            path = "C:\\Users\\yangtf\\Desktop\\Java.pdf"; // 绝对路径
            File file = new File(path);
            this.fileName = "JavaAnalysisReport.pdf";
            return new FileInputStream(file);
        }
        if ("PHP".equals(fileName)) {
            path = "C:\\Users\\yangtf\\Desktop\\PHP.pdf";
            File file = new File(path);
            this.fileName = "PHPAnalysisReport.pdf";
            return new FileInputStream(file);
        }
        return null;
    }
    
    @Override
    public String execute() throws Exception {
       return SUCCESS;
    }
}

<action name="fileDownload" class="com.tengfeiyang.action.FileDownloadAction">
            <result name="success" type="stream">
                <param name="contentDisposition">attachment;filename=${fileName}</param>
                <param name="inputName">downloadFile</param>
                <param name="bufferSize">1024</param>
            </result>
        </action>

<a href="fileDownload.action?fileName=Java">Java分析文档下载</a><br>
<a href="fileDownload.action?fileName=PHP">PHP分析文档下载</a>