java對ftp操作遇到的一系列的坑
阿新 • • 發佈:2019-02-05
首先讓我先講一下最近專案中遇到的伺服器主要使用的ftp伺服器構建工具 (IIS 、ser-u、filezilla)
IIS(摘錄自百度百科)
- IIS 是widow中IIS是一個World Wide Web server。Gopher server和FTP server全部包容在裡面。 IIS意味著你能釋出網頁,並且有ASP(Active Server Pages)、JAVA、VBscript產生頁面,有著一些擴充套件功能。IIS支援一些有趣的東西,像有編輯環境的介面(FRONTPAGE)、有全文檢索功能的(INDEX SERVER)、有多媒體功能的(NET SHOW) 其次,IIS是隨Windows NT Server 4.0一起提供的檔案和應用程式伺服器,是在Windows NT Server上建立Internet伺服器的基本元件。它與Windows NT Server完全整合,允許使用Windows NT Server內建的安全性以及NTFS檔案系統建立強大靈活的Internet/Intranet站點。IIS(Internet Information Server,網際網路資訊服務)是一種Web(網頁)服務元件,其中包括Web伺服器、FTP伺服器、NNTP伺服器和SMTP伺服器,分別用於網頁瀏覽、檔案傳輸、新聞服務和郵件傳送等方面,它使得在網路(包括網際網路和區域網)上釋出資訊成了一件很容易的事。
ser-u(摘錄自百度百科)
- Serv-U™ - Windows平臺的FTP伺服器軟體Serv-U 是目前眾多的FTP 伺服器軟體之一。通過使用Serv-U,使用者能夠將任何一臺PC 設定成一個FTP 伺服器,這樣,使用者或其他使用者就能夠使用FTP 協議,通過在同一網路上的任何一臺PC與FTP 伺服器連線,進行檔案或目錄的複製,移動,建立,和刪除等。這裡提到的FTP 協議是專門被用來規定計算機之間進行檔案傳輸的標準和規則,正是因為有了像FTP 這樣的專門協議,才使得人們能夠通過不同型別的計算機,使用不同型別的作業系統,對不同型別的檔案進行相互傳遞。
filezilla(摘錄百度百科)
- FileZilla是一個免費開源的FTP軟體,分為客戶端版本和伺服器版本,具備所有的FTP軟體功能。可控性、有條理的介面和管理多站點的簡化方式使得Filezilla客戶端版成為一個方便高效的FTP客戶端工具,而FileZilla Server則是一個小巧並且可靠的支援FTP&SFTP的FTP伺服器軟體。
java中操作ftp api-ftpclient
開始記錄在使用這兩個ftp構建工具遇到的一些問題(win7 平臺)
- ftp 某些方法 如listFile 等方法無效,卡死
這個問題是兩個工具中我都遇到了 ,這個問題是關於主動模和被動模式有關,這裡我貼出我在看了相關的博文的總結:
- 主動模式
是可以這樣想服務端的埠確定 比如命令埠21埠,還有資料埠20埠 主動連結放在客戶端,客戶端會開啟一個大於1023埠去連結伺服器21埠,還有開啟N+1埠去連結伺服器的資料埠,並監聽這兩個埠
而客戶端又要向服務端開放埠 ,這個是客戶端開發由外向內的埠連結(在資料埠上面),,,所以一般會被防火牆攔截 (埠隨機)
所以一般會出現可以連線上,但是訪問資料會出現異常的現象,就比如今天我用eclipse 的時候出現的問題,呼叫listFile 會出現卡死在建立socket上面了 - 被動模式
被動方式與主動方式不同的是,先是一樣的21埠連結,但是連結成功後,伺服器端先開啟一個數據埠,告知客戶端通過本地的埠來連線自己的這個開放的埠,一般的ftp伺服器都允許客戶端通過高階口位連結自己。
- 主動模式
卡死,由於ftpclient 操作預設是是通過主動模式 ,可以設定為被動模式(但是自己當時使用eclipse 會出現這個問題 ,使用idea卻沒有問題 ,跟蹤程式碼是在卡死在了建立socket上面)
ftpClient.enterLocalPassiveMode();
- ftp通過ser-u構建,出現的問題
ftpclient listFile方法無法返回正確的資料,一般返回時null ,使用listNames 返回的也是隻有檔名,這個是ftpclient 工具包的一個bug,這個有專門的大神分析了原始碼,並給出了多種的解決辦法,比如我使用了下面這種(分析太多,,有機會仔細看下)
ftpClient.configure(new FTPClientConfig("com.zznode.tnms.ra.c11n.nj.resource.ftp.UnixFTPEntryParser"));
奇怪的是使用IIS 構建的伺服器並不會出現這個問題
- 使用ser-u構建 ftp伺服器獲取檔案列表,會獲取當前目錄和上一級目錄
估計是為了相容linux 和window不同的平臺吧 ,,不是吧許可權模型也改成了和linux一樣的rwx嘛,但是IIS 不會反悔上一級和當前的目錄,所以如果是使用ser-u 構建的ftp,那麼在進行ftp檔案無限層級檢索的時候要記得過濾
. ..
這兩個目錄 ,不然會死迴圈~~~
filezilla 出現listfile為空的情況(好像是之前使用ser-u也出現類似的情況)
網上說是解決ftp支援系統中文環境,建立下面兩個類檔案:package com.xpp.util.filezillapatch; import java.text.ParseException; import java.text.ParsePosition; import java.text.SimpleDateFormat; import java.util.Calendar; import java.util.Date; import org.apache.commons.net.ftp.parser.FTPTimestampParserImpl; public class FTPTimestampParserImplExZH extends FTPTimestampParserImpl { private SimpleDateFormat defaultDateFormat = new SimpleDateFormat("mm d hh:mm"); private SimpleDateFormat recentDateFormat = new SimpleDateFormat("yyyy mm d"); private String formatDate_Zh2En(String timeStrZh) { if (timeStrZh == null) { return ""; } int len = timeStrZh.length(); StringBuffer sb = new StringBuffer(len); char ch = ' '; for (int i = 0; i < len; i++) { ch = timeStrZh.charAt(i); if ((ch >= '0' && ch <= '9') || ch == ' ' || ch == ':') { sb.append(ch); } } return sb.toString(); } /** * Implements the one {@link FTPTimestampParser#parseTimestamp(String) method} in the {@link FTPTimestampParser * FTPTimestampParser} interface according to this algorithm: If the recentDateFormat member has been defined, try * to parse the supplied string with that. If that parse fails, or if the recentDateFormat member has not been * defined, attempt to parse with the defaultDateFormat member. If that fails, throw a ParseException. * * @see org.apache.commons.net.ftp.parser.FTPTimestampParser#parseTimestamp(String) */ public Calendar parseTimestamp(String timestampStr) throws ParseException { timestampStr = formatDate_Zh2En(timestampStr); Calendar now = Calendar.getInstance(); now.setTimeZone(this.getServerTimeZone()); Calendar working = Calendar.getInstance(); working.setTimeZone(this.getServerTimeZone()); ParsePosition pp = new ParsePosition(0); Date parsed = null; if (this.recentDateFormat != null) { parsed = recentDateFormat.parse(timestampStr, pp); } if (parsed != null && pp.getIndex() == timestampStr.length()) { working.setTime(parsed); working.set(Calendar.YEAR, now.get(Calendar.YEAR)); if (working.after(now)) { working.add(Calendar.YEAR, -1); } } else { pp = new ParsePosition(0); parsed = defaultDateFormat.parse(timestampStr, pp); // note, length checks are mandatory for us since // SimpleDateFormat methods will succeed if less than // full string is matched. They will also accept, // despite "leniency" setting, a two-digit number as // a valid year (e.g. 22:04 will parse as 22 A.D.) // so could mistakenly confuse an hour with a year, // if we don't insist on full length parsing. if (parsed != null && pp.getIndex() == timestampStr.length()) { working.setTime(parsed); } else { throw new ParseException("Timestamp could not be parsed with older or recent DateFormat", pp.getIndex()); } } return working; } }
第二個檔案
package com.xpp.util.filezillapatch;
/*
* Copyright 2001-2005 The Apache Software Foundation
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
import java.text.ParseException;
import java.util.Calendar;
import org.apache.commons.net.ftp.FTPClientConfig;
import org.apache.commons.net.ftp.FTPFile;
import org.apache.commons.net.ftp.parser.ConfigurableFTPFileEntryParserImpl;
import org.apache.log4j.Logger;
/**
* 注:common-net-1.4.1.jar原始碼,修改對於日期中文格式的支援,從而解決FTPClient.listFiles()返回為空問題
* Implementation FTPFileEntryParser and FTPFileListParser for standard
* Unix Systems.
*
* This class is based on the logic of Daniel Savarese's
* DefaultFTPListParser, but adapted to use regular expressions and to fit the
* new FTPFileEntryParser interface.
* @version $Id: UnixFTPEntryParser.java 161712 2005-04-18 02:57:04Z scohen $
* @see org.apache.commons.net.ftp.FTPFileEntryParser FTPFileEntryParser (for usage instructions)
*/
public class UnixFTPEntryParser extends ConfigurableFTPFileEntryParserImpl
{
private static Logger logger = Logger.getLogger(UnixFTPEntryParser.class);
/**
* months abbreviations looked for by this parser. Also used
* to determine which month is matched by the parser
*/
private static final String DEFAULT_MONTHS =
"(Jan|Feb|Mar|Apr|May|Jun|Jul|Aug|Sep|Oct|Nov|Dec)";
static final String DEFAULT_DATE_FORMAT
= "MMM d yyyy"; //Nov 9 2001
static final String DEFAULT_RECENT_DATE_FORMAT
= "MMM d HH:mm"; //Nov 9 20:06
static final String NUMERIC_DATE_FORMAT
= "yyyy-MM-dd HH:mm"; //2001-11-09 20:06
/**
* Some Linux distributions are now shipping an FTP server which formats
* file listing dates in an all-numeric format:
* <code>"yyyy-MM-dd HH:mm</code>.
* This is a very welcome development, and hopefully it will soon become
* the standard. However, since it is so new, for now, and possibly
* forever, we merely accomodate it, but do not make it the default.
* <p>
* For now end users may specify this format only via
* <code>UnixFTPEntryParser(FTPClientConfig)</code>.
* Steve Cohen - 2005-04-17
*/
public static final FTPClientConfig NUMERIC_DATE_CONFIG =
new FTPClientConfig(
FTPClientConfig.SYST_UNIX,
NUMERIC_DATE_FORMAT,
null, null, null, null);
/**
* this is the regular expression used by this parser.
*
* Permissions:
* r the file is readable
* w the file is writable
* x the file is executable
* - the indicated permission is not granted
* L mandatory locking occurs during access (the set-group-ID bit is
* on and the group execution bit is off)
* s the set-user-ID or set-group-ID bit is on, and the corresponding
* user or group execution bit is also on
* S undefined bit-state (the set-user-ID bit is on and the user
* execution bit is off)
* t the 1000 (octal) bit, or sticky bit, is on [see chmod(1)], and
* execution is on
* T the 1000 bit is turned on, and execution is off (undefined bit-
* state)
*/
private static final String REGEX =
"([bcdlfmpSs-])"
+"(((r|-)(w|-)([xsStTL-]))((r|-)(w|-)([xsStTL-]))((r|-)(w|-)([xsStTL-])))\\+?\\s+"
+ "(\\d+)\\s+"
+ "(\\S+)\\s+"
+ "(?:(\\S+)\\s+)?"
+ "(\\d+)\\s+"
/*
numeric or standard format date
*/
//問題出在此處,這個匹配只匹配2中形式:
//(1)2008-08-03
//(2)Jan 9或4月 26
//而出錯的hp機器下的顯示為 8月20日(沒有空格分開)
//故無法匹配而報錯
//將下面字串改為:
+ "((?:\\d+[-/]\\d+[-/]\\d+)|(?:\\S+\\s+\\S+)|(?:\\S+))\\s+"
//+ "((?:\\d+[-/]\\d+[-/]\\d+)|(?:\\S+\\s+\\S+))\\s+"
/*
year (for non-recent standard format)
or time (for numeric or recent standard format
*/
+ "(\\d+(?::\\d+)?)\\s+"
+ "(\\S*)(\\s*.*)";
/**
* The default constructor for a UnixFTPEntryParser object.
*
* @exception IllegalArgumentException
* Thrown if the regular expression is unparseable. Should not be seen
* under normal conditions. It it is seen, this is a sign that
* <code>REGEX</code> is not a valid regular expression.
*/
public UnixFTPEntryParser()
{
this(null);
}
/**
* This constructor allows the creation of a UnixFTPEntryParser object with
* something other than the default configuration.
*
* @param config The {@link FTPClientConfig configuration} object used to
* configure this parser.
* @exception IllegalArgumentException
* Thrown if the regular expression is unparseable. Should not be seen
* under normal conditions. It it is seen, this is a sign that
* <code>REGEX</code> is not a valid regular expression.
* @since 1.4
*/
public UnixFTPEntryParser(FTPClientConfig config)
{
super(REGEX);
configure(config);
}
/**
* Parses a line of a unix (standard) FTP server file listing and converts
* it into a usable format in the form of an <code> FTPFile </code>
* instance. If the file listing line doesn't describe a file,
* <code> null </code> is returned, otherwise a <code> FTPFile </code>
* instance representing the files in the directory is returned.
* <p>
* @param entry A line of text from the file listing
* @return An FTPFile instance corresponding to the supplied entry
*/
public FTPFile parseFTPEntry(String entry) {
FTPFile file = new FTPFile();
file.setRawListing(entry);
int type;
boolean isDevice = false;
if (matches(entry))
{
String typeStr = group(1);
String hardLinkCount = group(15);
String usr = group(16);
String grp = group(17);
String filesize = group(18);
String datestr = group(19) + " " + group(20);
String name = group(21);
String endtoken = group(22);
try
{
//file.setTimestamp(super.parseTimestamp(datestr));
FTPTimestampParserImplExZH Zh2En = new FTPTimestampParserImplExZH();
file.setTimestamp(Zh2En.parseTimestamp(datestr));
}
catch (ParseException e)
{
//logger.error(e, e);
//return null; // this is a parsing failure too.
//logger.info(entry+":修改日期重置為當前時間");
file.setTimestamp(Calendar.getInstance());
}
// bcdlfmpSs-
switch (typeStr.charAt(0))
{
case 'd':
type = FTPFile.DIRECTORY_TYPE;
break;
case 'l':
type = FTPFile.SYMBOLIC_LINK_TYPE;
break;
case 'b':
case 'c':
isDevice = true;
// break; - fall through
case 'f':
case '-':
type = FTPFile.FILE_TYPE;
break;
default:
type = FTPFile.UNKNOWN_TYPE;
}
file.setType(type);
int g = 4;
for (int access = 0; access < 3; access++, g += 4)
{
// Use != '-' to avoid having to check for suid and sticky bits
file.setPermission(access, FTPFile.READ_PERMISSION,
(!group(g).equals("-")));
file.setPermission(access, FTPFile.WRITE_PERMISSION,
(!group(g + 1).equals("-")));
String execPerm = group(g + 2);
if (!execPerm.equals("-") && !Character.isUpperCase(execPerm.charAt(0)))
{
file.setPermission(access, FTPFile.EXECUTE_PERMISSION, true);
}
else
{
file.setPermission(access, FTPFile.EXECUTE_PERMISSION, false);
}
}
if (!isDevice)
{
try
{
file.setHardLinkCount(Integer.parseInt(hardLinkCount));
}
catch (NumberFormatException e)
{
// intentionally do nothing
}
}
file.setUser(usr);
file.setGroup(grp);
try
{
file.setSize(Long.parseLong(filesize));
}
catch (NumberFormatException e)
{
// intentionally do nothing
}
if (null == endtoken)
{
file.setName(name);
}
else
{
// oddball cases like symbolic links, file names
// with spaces in them.
name += endtoken;
if (type == FTPFile.SYMBOLIC_LINK_TYPE)
{
int end = name.indexOf(" -> ");
// Give up if no link indicator is present
if (end == -1)
{
file.setName(name);
}
else
{
file.setName(name.substring(0, end));
file.setLink(name.substring(end + 4));
}
}
else
{
file.setName(name);
}
}
return file;
} else {
logger.info("matches(entry) failure:"+entry);
}
return null;
}
/**
* Defines a default configuration to be used when this class is
* instantiated without a {@link FTPClientConfig FTPClientConfig}
* parameter being specified.
* @return the default configuration for this parser.
*/
protected FTPClientConfig getDefaultConfiguration() {
return new FTPClientConfig(
FTPClientConfig.SYST_UNIX,
DEFAULT_DATE_FORMAT,
DEFAULT_RECENT_DATE_FORMAT,
null, null, null);
}
}
然後在你連線ftp的地方加上
ftp.configure(new FTPClientConfig("com.xpp.util.filezillapatch.UnixFTPEntryParser"));
這樣就能返回正常的資料了