struts2文件上传，下载

1. 页面表单

<HTML><HEAD><TITLE>上传下载图片</TITLE><meta http-equiv="Content-Type" content="text/html; charset=GBK"></head><body><form enctype="multipart/form-data" action="hello/fileUploadAction!fileUpload" method="post"><table><tr><td>文件：</td><td><input type="file" name="uploadImage"></td></tr><tr><td colspan="2"><input type="submit" value="upload"><input type="reset" value="重 置"></td></tr></table><img alt="qian" src="hello/fileUploadAction!fileDownload"></form></body>
</html>

2. 上传下载实现

package action;import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.UUID;import org.apache.commons.io.FileUtils;import base.BaseAction;public class FileUploadAction extends BaseAction {private static final long serialVersionUID = 1L;// uploadImage 为表单文件名称private File uploadImage;private String uploadImageFileName; // 文件名 private String uploadImageContentType; // 文件类型public File getUploadImage() {return uploadImage;}public void setUploadImage(File uploadImage) {this.uploadImage = uploadImage;}public String getUploadImageFileName() {return uploadImageFileName;}public void setUploadImageFileName(String uploadImageFileName) {this.uploadImageFileName = uploadImageFileName;}public String getUploadImageContentType() {return uploadImageContentType;}public void setUploadImageContentType(String uploadImageContentType) {this.uploadImageContentType = uploadImageContentType;}public String fileUpload() {String path = "E:ssh\\struts2\\Struts_06\\fileDir";// 创建存储文件的文件夹File fileDir = new File(path);if (!fileDir.exists()) {fileDir.mkdirs();}int count = uploadImageFileName.lastIndexOf(".");// 得到文件后缀名String ext = uploadImageFileName.substring(count);UUID uuid = UUID.randomUUID();String fileName = uuid + ext;File file = new File(path + "\\" + fileName);if (!file.exists()) {try {// 创建文件file.createNewFile();} catch (IOException e) {e.printStackTrace();}}try {// 复制文件到上传的路径FileUtils.copyFile(uploadImage, file);} catch (IOException e) {e.printStackTrace();}return "index";}public void fileDownload() {File file = new File("E:ssh\\struts2\\Struts_06\\fileDir\\4fcd0f06-575a-47fc-a010-d0a232ef9947.jpg");System.out.println(file);// 清除空格resp.reset();// 设置文件 ContentType 自动判断下载类型resp.setContentType("multipart/form-data");// 设置文件头resp.setHeader("Content-Disposition", "attachment;fileName="+file.getName());InputStream in = null;OutputStream out = null;try {in = new FileInputStream(file);out = resp.getOutputStream();// 准备字节数组装 byte[] b = new byte[(int)file.length()];// 将文件读取到内存中in.read(b);// 使用response响应流 写到页面out.write(b);} catch (FileNotFoundException e) {e.printStackTrace();} catch (IOException e) {e.printStackTrace();} finally {try {if (out != null)out.close();if (in != null)in.close();} catch (IOException e) {e.printStackTrace();}}}public static void main(String[] args) {String str = "fhh.jpg";int i = str.lastIndexOf(".");String string = str.substring(i);System.out.println(string);}}