Jsp实现筛选并压缩文件批量下载
首先明确一下需求，网页端点击一下button，传递特定的参数到download.jsp网页，筛选文件，对过滤得到的文件进行压缩，然后返回前端一个压缩包下载。
以下的代码来源于网络，没找到源发地出处，经过了自定义的修改。
方法声明
<%@ page
language="java"
import="java.util.*"
%>
<%@ page import="java.io.BufferedInputStream" %>
<%@ page import="java.io.File" %>
<%@ page import="java.io.FileFilter" %>
<%@ page import="java.io.FileInputStream" %>
<%@ page import="java.io.FileOutputStream" %>
<%@ page import="java.io.IOException" %>
<%@ page import="java.io.InputStream" %>
<%@ page import="org.apache.tools.zip.*" %>
<%@ page import="javax.servlet.http.HttpServletResponse" %>
<%@ page import="java.util.zip.*" %>
<%@ page import="java.util.regex.Pattern" %>
<%@ page import="java.util.regex.Matcher" %>
<%!
// 得到该文件夹，及其所有子文件夹下的所有目标文件
List<File> getAllFiles(File file, String regex) {
List<File> valueFiles = new ArrayList<File>();
File[] fs = file.listFiles();
for (int i = 0; i < fs.length; i++) {
if (fs[i].isDirectory()) {
// 递归得到每个子文件夹下的目标文件
valueFiles.addAll(getAllFiles(fs[i], regex));
}
}
// 把file文件夹下的目标文件放进去
valueFiles.addAll(Arrays.asList(getFiles(file, regex)));
return valueFiles;
}
// 得到一个文件夹下的目标文件，不包括子文件夹
File[] getFiles(File file, String _regex) {
final String regexTemp = _regex;
// 图个方便，用匿名类了
FileFilter filter = new FileFilter() {
String regex = regexTemp;
public boolean accept(File pathname) {
// return pathname.getName().matches(regex);// 文件后缀为.jsp
Pattern pattern = Pattern.compile(regex);
Matcher matcher = pattern.matcher(pathname.getName());
return matcher.find();
}
};
File[] fs = file.listFiles(filter);
return fs;
}
String[] listToStringArray(List<File> listF) {
List<String> listS = new ArrayList<String>();
for (File f : listF) {
listS.add(f.getAbsolutePath());
}
int size = listS.size();
return (String[])listS.toArray(new String[size]);
}
public class JspFileDownload {
/** request object */
private HttpServletResponse response = null;
/** file type: -1 un-setting; 0 normal file; 1 zip file ;2 stream*/
private int fileType = -1;
/** file name to be displayed */
private String disFileName = null;
/** zip file path */
private String zipFilePath = null;
/** file to be zipped */
private String[] zipFileNames = null;
private boolean zipDelFlag = false;
/** file to be downloaded */
private String downFileName = null;
/** error code 0 */
private static final int PROCESS_OK = 0;
/** error code 1 */
private static final int RESPONSE_IS_NULL = 1;
/** error code 2 */
private static final int UNSET_DOWNLOADTYPE = 2;
/** error code 3 */
private static final int UNSET_DIS_FILE_NAME = 3;
/** error code 4 */
private static final int UNSET_DOWN_FILE_NAME = 4;
/** error code 9 */
private static final int IO_EXCEPTION = 9;
/**
* set response object
* @param response response Object
*/
public void setResponse(HttpServletResponse response){
this.response = response;
}
/**
* set file type 0 normal file; 1 zip file ;2 stream
* @param fileType
*/
public void setDownType(int fileType){
this.fileType = fileType;
}
/**
* set display file name
* @param fileName
*/
public void setDisFileName(String fileName){
this.disFileName = fileName;
}
/**
* set zip file path
* @param fileNames
*/
public void setZipFilePath( String path ){
this.zipFilePath = path;
}
public void setZipDelFlag(boolean b){
this.zipDelFlag = b;
}
/**
* set zip file names
* @param fileNames
*/
public void setZipFileNames(String[] fileNames){
this.zipFileNames = fileNames;
}
/**
* set download file name
* @param fileName
*/
public void setDownFileName(String fileName){
this.downFileName = fileName;
}
/**
* set file content
* @param fileContent
*/
public int setFileContent(String fileContent){
try{
// byte[] buffs = fileContent.getBytes("GBK");
byte[] buffs = fileContent.getBytes("UTF-8");
response.getOutputStream().write(buffs);
}catch(IOException e){
return IO_EXCEPTION;
}
return PROCESS_OK;
}
/**
* set file content
* @param fileContent
*/
public int setFileContent(byte[] fileContent){
try{
response.getOutputStream().write(fileContent);
}catch(IOException e){
return IO_EXCEPTION;
}
return PROCESS_OK;
}
/**
* set file content end
*
*/
public int setFileContentEnd(){
try{
response.getOutputStream().close();
}catch(IOException e){
return IO_EXCEPTION;
}
return PROCESS_OK;
}
/**
* main process
* @return
*/
public int process(){
int status = PROCESS_OK;
status = preCheck();
if ( status != PROCESS_OK )
return status;
String fileName = disFileName;
response.setContentType("APPLICATION/OCTET-STREAM");
response.setHeader("Content-Disposition","attachment;filename=\"" + fileName + "\"");
int BUFSIZE = 1024 * 8;
int rtnPos = 0;
byte[] buffs = new byte[ BUFSIZE ];
FileInputStream inStream = null;
ZipOutputStream zos = null;
InputStream is = null;
String filepath = null;
try{
if ( fileType == 0 || fileType == 1){
if ( fileType == 0 ){
filepath = downFileName;
} else {
filepath = zipFilePath + fileName;
String[] fileToZip = zipFileNames;
zos=new ZipOutputStream(new FileOutputStream(filepath));
ZipEntry ze=null;
byte[] buf=new byte[BUFSIZE];
int readLen=0;
for (int i= 0;i<fileToZip.length;i++){
File f= new File(fileToZip[i]);
ze=new ZipEntry(f.getName());
ze.setSize(f.length());
ze.setTime(f.lastModified());
zos.putNextEntry(ze);
is=new BufferedInputStream(new FileInputStream(f));
while ((readLen=is.read(buf, 0, BUFSIZE))!=-1) {
zos.write(buf, 0, readLen);
}
is.close();
}
zos.close();
}
// 以下为输出文件
inStream =new FileInputStream(filepath);
while((rtnPos=inStream.read(buffs)) >0)
response.getOutputStream().write(buffs,0,rtnPos);
response.getOutputStream().close();
inStream.close();
}
if ( zipDelFlag ){
File fToDel = new File(filepath);
fToDel.delete();
}
}catch(IOException e){
return IO_EXCEPTION;
}finally{
try{
if ( inStream != null ){
inStream.close();
inStream = null;
}
if ( zos != null ){
zos.close();
zos = null;
}
if ( is != null ){
is.close();
is = null;
}
}catch (IOException e){
}
}
return status;
}
/**
* pre check.
* @return
*/
private int preCheck(){
if ( response == null )
return RESPONSE_IS_NULL;
if ( disFileName == null || disFileName.trim().length() == 0 )
return UNSET_DIS_FILE_NAME;
if ( fileType == -1 )
return UNSET_DOWNLOADTYPE;
else if ( fileType == 0 ){
if ( downFileName == null || downFileName.trim().length() == 0 )
return UNSET_DOWN_FILE_NAME;
else{
if ( !isFile( downFileName ) )
return UNSET_DOWN_FILE_NAME;
}
}else if ( fileType == 1 ){
if ( zipFilePath == null || zipFilePath.length() == 0 )
return UNSET_DOWN_FILE_NAME;
else{
if ( !isDirect(zipFilePath) )
return UNSET_DOWN_FILE_NAME;
}
if ( zipFileNames == null || zipFileNames.length == 0 )
return UNSET_DOWN_FILE_NAME;
else{
for ( int i=0;i<zipFileNames.length;i++ ){
if ( zipFileNames[i] == null || zipFileNames[i].trim().length() == 0 )
return UNSET_DOWN_FILE_NAME;
else{
if ( !isFile( zipFileNames[i] ) )
return UNSET_DOWN_FILE_NAME;
}
}
}
}else if ( fileType == 2 ){
//doing nothing
}else{
return UNSET_DOWNLOADTYPE;
}
return PROCESS_OK;
}
private boolean isFile(String fileName){
File f = new File(fileName);
if (!f.exists() || !f.isFile())
return false;
return true;
}
private boolean isDirect(String filePath){
File f = new File(filePath);
if (!f.exists() || !f.isDirectory())
return false;
return true;
}
}
%>
代码调用
<%@ include file="downloadFilesHelper.jsp" %>
<%
// 服务器路径
String filePath = request.getRealPath("/") + "homeworkUpload\\";
// 构建路径File
File path = new File(filePath);
// 正则表达式
String homeworkNamePrefix = request.getParameter("homeworkNamePrefix");
// String homeworkNamePrefix = "数据库第一周作业";
String regex = "^(" + homeworkNamePrefix + ")";
// String regex = "^(数据库第一周作业)";
// 获取文件List
List<File> listFiles = getAllFiles(path, regex);
// List转String[]
String[] files = listToStringArray(listFiles);
// 压缩文件名
// String outputFileName = "批量下载" + homeworkNamePrefix + ".zip";
String outputFileName = "Homework.zip";
// 准备压缩
JspFileDownload jspFileDownload = new JspFileDownload();
jspFileDownload.setResponse(response);
jspFileDownload.setDownType(1); // zip file
jspFileDownload.setDisFileName(outputFileName);
jspFileDownload.setZipFilePath(filePath);
jspFileDownload.setZipDelFlag(false); // 不删除压缩文件
jspFileDownload.setZipFileNames(files);
jspFileDownload.setDownFileName(outputFileName);
// jspFileDownload.setFileContent(homeworkNamePrefix);
// jspFileDownload.setFileContentEnd();
// 开始压缩并下载
int status = jspFileDownload.process();
// Debug
// out.println("status = " + status + "<br/>");
// out.println("regex = " + regex + "<br/>");
// for (int i = 0; i < files.length; i++) {
// out.println(files[i] + "<br/>");
// }
// out.println(outputFileName + "<br/>");
if (status == 4) {
out.println("<p>还没有同学上交作业</p>");
}
%>
已知bug，outputFileName不能赋值为中文名，如果赋值为中文名，返回前端的压缩包名字为------.zip，但内容一点问题都没有。暂时没有解决，如果有园友解决了的，求告知。
至此，完毕。