struts2 文件的上传和下载

    在Web项目中导入支持文件上传下载和IO输入输出的两个jar包。它们名字为commons-fileupload-1.2.1.jar和commons-io-1.4.jar

     

package com.example.struts.action;

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 java.io.OutputStream;
import java.util.List;

import org.apache.struts2.ServletActionContext;

import com.opensymphony.xwork2.ActionSupport;

public class UploadAction extends ActionSupport {
	//上传文件存放路径
	private final static String UPLOADDIR = "/upload";
	//上传文件集合
	private List<File> file;
	//上传文件名集合
	private List<String> fileFileName;
	//上传文件内容类型集合
	private List<String> fileContentType;

	public List<File> getFile() {
		return file;
	}

	public void setFile(List<File> file) {
		this.file = file;
	}

	public List<String> getFileFileName() {
		return fileFileName;
	}

	public void setFileFileName(List<String> fileFileName) {
		this.fileFileName = fileFileName;
	}

	public List<String> getFileContentType() {
		return fileContentType;
	}

	public void setFileContentType(List<String> fileContentType) {
		this.fileContentType = fileContentType;
	}

	public String execute() throws Exception {
		for (int i = 0; i < file.size(); i++) {
			//循环上传每个文件
			uploadFile(i);
		}
		return "success";
	}

	//执行上传功能
	private void uploadFile(int i) throws FileNotFoundException, IOException {
		try {
			InputStream in = new FileInputStream(file.get(i));
			String dir = ServletActionContext.getRequest().getRealPath(UPLOADDIR);
			File uploadFile = new File(dir, this.getFileFileName().get(i));
			OutputStream out = new FileOutputStream(uploadFile);
			byte[] buffer = new byte[1024 * 1024];
			int length;
			while ((length = in.read(buffer)) > 0) {
				out.write(buffer, 0, length);
			}

			in.close();
			out.close();
		} catch (FileNotFoundException ex) {
			ex.printStackTrace();
		} catch (IOException ex) {
			ex.printStackTrace();
		}
	}


}

 “fileFileName”和“fileContentType”读者看了有点别扭，尤其是“fileFileName”感觉不符合Java命名规范，但是这两个属性变量是“fileUpload”拦截器类中的类公有变量名字，只有这样定义，UploadAction执行时候会把在页面上选择的上传文件的属性值放在这两个变量里面!

package com.example.struts.action;

import java.io.InputStream;
import java.io.UnsupportedEncodingException;

import org.apache.struts2.ServletActionContext;

import com.opensymphony.xwork2.ActionSupport;

public class DownLoadAction extends ActionSupport {
	//下载文件原始存放路径
	private final static String DOWNLOADFILEPATH="/upload/";
	//文件名参数变量
	private String fileName;

	public String getFileName() {
		return fileName;
	}

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

	//从下载文件原始存放路径读取得到文件输出流
	public InputStream getDownloadFile() {
		return 
	ServletActionContext.getServletContext().getResourceAsStream(DOWNLOADFILEPATH+fileName);
	}
	//如果下载文件名为中文，进行字符编码转换
	public String getDownloadChineseFileName() {
		String downloadChineseFileName = fileName;

		try {
			downloadChineseFileName = new String(downloadChineseFileName.getBytes(), "ISO8859-1");
		} catch (UnsupportedEncodingException e) {
			e.printStackTrace();
		}

		return downloadChineseFileName;
	}

	public String execute() {
		return SUCCESS;
	}


}

 

	<!-- 上传文件表单定义 -->
	<s:form action="upload.action" method="post" enctype="multipart/form-data">
		<tr>
	<!-- 上传文件标签定义 -->
	<td>上传文件:<s:file name="file"></s:file></td>
	</tr>
	<tr>
	<td>再次上传文件:<s:file name="file"></s:file></td>
	</tr>
	<tr>
	<td align="left"><s:submit name="submit" value="提交"></s:submit></td>
	</tr>
	</s:form>

 

上传文件：
			<table>
		<!-- 循环显示上传成功文件名 -->
		<s:iterator value="fileFileName" status="fn">
		<tr>
		<td>
		<!-- 上传成功文件名 -->
		<s:property />		
		</td>
		<td>
		<!-- 下载文件链接内容为定义的下载Action -->
		<!-- 下载文件名作为链接参数fileName值，用OGNL表达式表达 -->	
		<a href="<s:url value='download.action'>  				
                 	<s:param name='fileName'
 value='fileFileName[#fn.getIndex()]'/>  
                 </s:url>">下载</a>
		</td>
		</tr>
		</s:iterator>		
		</table>	

 

	<package name="C01" extends="struts-default" namespace="/">
	<!-- 通过Action类处理才导航的的Action定义 -->
		<action name="upload" class="com.example.struts.action.UploadAction">
			<result name="input">/jsp/upload.jsp</result>
			<result name="success">/jsp/result.jsp</result>
			<!--显示配置文件上传拦截器  -->
			<interceptor-ref name="fileUpload">
			<!--指定特定类型的上传文件  -->
			<param name ="allowedTypes">text/plain,application/xml</param>
			</interceptor-ref >
			<interceptor-ref name="defaultStack"></interceptor-ref >
		</action>
	<!-- 下载文件的Action定义 -->
		<action name="download" class="com.example.struts.action.DownLoadAction">
			<!-- 设置文件名参数，由页面上传入 -->
			<param name="fileName"></param>
			<result name="success" type="stream">
				<!-- 下载文件类型定义 -->
				<param name="contentType">text/plain</param>
				<!-- 下载文件处理方法 -->
				<param name="contentDisposition">
					attachment;filename="${downloadChineseFileName}"
				</param>
				<!-- 下载文件输出流定义 -->
				<param name="inputName">downloadFile</param>
			</result>
		</action>
    <action name="index">
    	<result>/jsp/upload.jsp
    	</result>
    </action>
	</package>

 定义了一个名为“allowedTypes”的参数，其中在<param></param>之间的是文件类型，也可以用“，”间隔，表示允许上传多个文件类型txt、xml格式的文件

'.a'      : 'application/octet-stream', 
'.ai'     : 'application/postscript', 
'.aif'    : 'audio/x-aiff', 
'.aifc'   : 'audio/x-aiff', 
'.aiff'   : 'audio/x-aiff', 
'.au'     : 'audio/basic', 
'.avi'    : 'video/x-msvideo', 
'.bat'    : 'text/plain', 
'.bcpio' : 'application/x-bcpio', 
'.bin'    : 'application/octet-stream', 
'.bmp'    : 'image/x-ms-bmp', 
'.c'      : 'text/plain', 
# Duplicates 
'.cdf'    : 'application/x-cdf', 
'.cdf'    : 'application/x-netcdf', 
'.cpio'   : 'application/x-cpio', 
'.csh'    : 'application/x-csh', 
'.css'    : 'text/css', 
'.dll'    : 'application/octet-stream', 
'.doc'    : 'application/msword', 
'.dot'    : 'application/msword', 
'.dvi'    : 'application/x-dvi', 
'.eml'    : 'message/rfc822', 
'.eps'    : 'application/postscript', 
'.etx'    : 'text/x-setext', 
'.exe'    : 'application/octet-stream', 
'.gif'    : 'image/gif', 
'.gtar'   : 'application/x-gtar', 
'.h'      : 'text/plain', 
'.hdf'    : 'application/x-hdf', 
'.htm'    : 'text/html', 
'.html'   : 'text/html', 
'.ief'    : 'image/ief', 
'.jpe'    : 'image/jpeg', 
'.jpeg'   : 'image/jpeg', 
'.jpg'    : 'image/jpeg', 
'.js'     : 'application/x-javascript', 
'.ksh'    : 'text/plain', 
'.latex' : 'application/x-latex', 
'.m1v'    : 'video/mpeg', 
'.man'    : 'application/x-troff-man', 
'.me'     : 'application/x-troff-me', 
'.mht'    : 'message/rfc822', 
'.mhtml' : 'message/rfc822', 
'.mif'    : 'application/x-mif', 
'.mov'    : 'video/quicktime', 
'.movie' : 'video/x-sgi-movie', 
'.mp2'    : 'audio/mpeg', 
'.mp3'    : 'audio/mpeg', 
'.mpa'    : 'video/mpeg', 
'.mpe'    : 'video/mpeg', 
'.mpeg'   : 'video/mpeg', 
'.mpg'    : 'video/mpeg', 
'.ms'     : 'application/x-troff-ms', 
'.nc'     : 'application/x-netcdf', 
'.nws'    : 'message/rfc822', 
'.o'      : 'application/octet-stream', 
'.obj'    : 'application/octet-stream', 
'.oda'    : 'application/oda', 
'.p12'    : 'application/x-pkcs12', 
'.p7c'    : 'application/pkcs7-mime', 
'.pbm'    : 'image/x-portable-bitmap', 
'.pdf'    : 'application/pdf', 
'.pfx'    : 'application/x-pkcs12', 
'.pgm'    : 'image/x-portable-graymap', 
'.pl'     : 'text/plain', 
'.png'    : 'image/png', 
'.pnm'    : 'image/x-portable-anymap', 
'.pot'    : 'application/vnd.ms-powerpoint', 
'.ppa'    : 'application/vnd.ms-powerpoint', 
'.ppm'    : 'image/x-portable-pixmap', 
'.pps'    : 'application/vnd.ms-powerpoint', 
'.ppt'    : 'application/vnd.ms-powerpoint', 
'.ps'     : 'application/postscript', 
'.pwz'    : 'application/vnd.ms-powerpoint', 
'.py'     : 'text/x-python', 
'.pyc'    : 'application/x-python-code', 
'.pyo'    : 'application/x-python-code', 
'.qt'     : 'video/quicktime', 
'.ra'     : 'audio/x-pn-realaudio', 
'.ram'    : 'application/x-pn-realaudio', 
'.ras'    : 'image/x-cmu-raster', 
'.rdf'    : 'application/xml', 
'.rgb'    : 'image/x-rgb', 
'.roff'   : 'application/x-troff', 
'.rtx'    : 'text/richtext', 
'.sgm'    : 'text/x-sgml', 
'.sgml'   : 'text/x-sgml', 
'.sh'     : 'application/x-sh', 
'.shar'   : 'application/x-shar', 
'.snd'    : 'audio/basic', 
'.so'     : 'application/octet-stream', 
'.src'    : 'application/x-wais-source', 
'.sv4cpio': 'application/x-sv4cpio', 
'.sv4crc' : 'application/x-sv4crc', 
'.swf'    : 'application/x-shockwave-flash', 
'.t'      : 'application/x-troff', 
'.tar'    : 'application/x-tar', 
'.tcl'    : 'application/x-tcl', 

'.tex'    : 'application/x-tex', 
'.texi'   : 'application/x-texinfo', 
'.texinfo': 'application/x-texinfo', 
'.tif'    : 'image/tiff', 
'.tiff'   : 'image/tiff', 
'.tr'     : 'application/x-troff', 
'.tsv'    : 'text/tab-separated-values', 
'.txt'    : 'text/plain', 
'.ustar' : 'application/x-ustar', 
'.vcf'    : 'text/x-vcard', 
'.wav'    : 'audio/x-wav', 
'.wiz'    : 'application/msword', 
'.wsdl'   : 'application/xml', 
'.xbm'    : 'image/x-xbitmap', 
'.xlb'    : 'application/vnd.ms-excel', 
# Duplicates 
'.xls'    : 'application/excel', 
'.xls'    : 'application/vnd.ms-excel', 
'.xml'    : 'text/xml', 
'.xpdl'   : 'application/xml', 
'.xpm'    : 'image/x-xpixmap', 
'.xsl'    : 'application/xml', 
'.xwd'    : 'image/x-xwindowdump', 
'.zip'    : 'application/zip', 

firefox 和 ie 的文件类型区别 
Java代码 
firefox image/jpeg image/bmp image/gif image/png  

ie 6 image/pjpeg image/bmp image/gif image/x-png  

ie 7 image/pjpeg image/bmp image/gif image/x-png  

ie 8 image/pjpeg image/bmp image/gif image/x-png

 。这里允许上传文件类型为