should use yyyy instead of YYYY in SimpleDateFormat

src/main/java/org/apache/commons/net/examples/mail/IMAPExportMbox.java

@@ -90,7 +90,7 @@ private static class MboxListener implements IMAPChunkListener {
         volatile long lastSeq = -1;
         private final String lineSeparator;
         private final SimpleDateFormat DATE_FORMAT // for mbox From_ lines
-            = new SimpleDateFormat("EEE MMM dd HH:mm:ss YYYY");
+            = new SimpleDateFormat("EEE MMM dd HH:mm:ss yyyy");
 
         // e.g. INTERNALDATE "27-Oct-2013 07:43:24 +0000"
         // for parsing INTERNALDATE

src/main/java/org/apache/commons/net/examples/mail/POP3ExportMbox.java

@@ -184,7 +184,7 @@ private static void writeFile(final POP3Client pop3, final OutputStreamWriter fw
 
     private static void writeMbox(final POP3Client pop3, final OutputStreamWriter fw, final int i) throws IOException {
         final SimpleDateFormat DATE_FORMAT // for mbox From_ lines
-                = new SimpleDateFormat("EEE MMM dd HH:mm:ss YYYY");
+                = new SimpleDateFormat("EEE MMM dd HH:mm:ss yyyy");
         final String replyTo = "MAILER-DAEMON"; // default
         final Date received = new Date();
         try (final BufferedReader r = (BufferedReader) pop3.retrieveMessage(i)) {

src/main/java/org/apache/commons/net/ftp/FTP.java

@@ -993,7 +993,7 @@ public int mdtm(final String file) throws IOException
      * receive the reply, and return the reply code.
      *
      * @param pathname The pathname for which mtime is to be changed
-     * @param timeval Timestamp in <code>YYYYMMDDhhmmss</code> format
+     * @param timeval Timestamp in <code>yyyyMMDDhhmmss</code> format
      * @return The reply code received from the server.
      * @throws FTPConnectionClosedException
      *      If the FTP server prematurely closes the connection as a result

src/main/java/org/apache/commons/net/ftp/FTPClient.java

@@ -1891,11 +1891,11 @@ public boolean getListHiddenFiles() {
     /**
      * Issue the FTP MDTM command (not supported by all servers) to retrieve the last
      * modification time of a file. The modification string should be in the
-     * ISO 3077 form "YYYYMMDDhhmmss(.xxx)?". The timestamp represented should also be in
+     * ISO 3077 form "yyyyMMDDhhmmss(.xxx)?". The timestamp represented should also be in
      * GMT, but not all FTP servers honor this.
      *
      * @param pathname The file path to query.
-     * @return A string representing the last file modification time in <code>YYYYMMDDhhmmss</code> format.
+     * @return A string representing the last file modification time in <code>yyyyMMDDhhmmss</code> format.
      * @throws IOException if an I/O error occurs.
      * @since 2.0
      */
@@ -2943,7 +2943,7 @@ public boolean makeDirectory(final String pathname) throws IOException
     /**
      * Issue the FTP MDTM command (not supported by all servers) to retrieve the last
      * modification time of a file. The modification string should be in the
-     * ISO 3077 form "YYYYMMDDhhmmss(.xxx)?". The timestamp represented should also be in
+     * ISO 3077 form "yyyyMMDDhhmmss(.xxx)?". The timestamp represented should also be in
      * GMT, but not all FTP servers honor this.
      *
      * @param pathname The file path to query.
@@ -2963,7 +2963,7 @@ public Calendar mdtmCalendar(final String pathname) throws IOException {
     /**
      * Issue the FTP MDTM command (not supported by all servers) to retrieve the last
      * modification time of a file. The modification string should be in the
-     * ISO 3077 form "YYYYMMDDhhmmss(.xxx)?". The timestamp represented should also be in
+     * ISO 3077 form "yyyyMMDDhhmmss(.xxx)?". The timestamp represented should also be in
      * GMT, but not all FTP servers honor this.
      *
      * @param pathname The file path to query.
@@ -2987,7 +2987,7 @@ public FTPFile mdtmFile(final String pathname) throws IOException {
     /**
      * Issue the FTP MDTM command (not supported by all servers) to retrieve the last
      * modification time of a file. The modification string should be in the
-     * ISO 3077 form "YYYYMMDDhhmmss(.xxx)?". The timestamp represented should also be in
+     * ISO 3077 form "yyyyMMDDhhmmss(.xxx)?". The timestamp represented should also be in
      * GMT, but not all FTP servers honor this.
      *
      * @param pathname The file path to query.
@@ -3746,14 +3746,14 @@ public void setListHiddenFiles(final boolean listHiddenFiles) {
      * Issue the FTP MFMT command (not supported by all servers) which sets the last
      * modified time of a file.
      *
-     * The timestamp should be in the form <code>YYYYMMDDhhmmss</code>. It should also
+     * The timestamp should be in the form <code>yyyyMMDDhhmmss</code>. It should also
      * be in GMT, but not all servers honor this.
      *
      * An FTP server would indicate its support of this feature by including "MFMT"
      * in its response to the FEAT command, which may be retrieved by FTPClient.features()
      *
      * @param pathname The file path for which last modified time is to be changed.
-     * @param timeval The timestamp to set to, in <code>YYYYMMDDhhmmss</code> format.
+     * @param timeval The timestamp to set to, in <code>yyyyMMDDhhmmss</code> format.
      * @return true if successfully set, false if not
      * @throws IOException if an I/O error occurs.
      * @since 2.2

src/main/java/org/apache/commons/net/ftp/parser/MLSxEntryParser.java

@@ -97,7 +97,7 @@ public static FTPFile parseEntry(final String entry) {
     }
 
     /**
-     * Parse a GMT time stamp of the form YYYYMMDDHHMMSS[.sss]
+     * Parse a GMT time stamp of the form yyyyMMDDHHMMSS[.sss]
      *
      * @param timestamp the date-time to parse
      * @return a Calendar entry, may be {@code null}
@@ -131,7 +131,7 @@ public static Calendar parseGMTdateTime(final String timestamp) {
     }
 
     /**
-     * Parse a GMT time stamp of the form YYYYMMDDHHMMSS[.sss]
+     * Parse a GMT time stamp of the form yyyyMMDDHHMMSS[.sss]
      *
      * @param timestamp the date-time to parse
      * @return a Calendar entry, may be {@code null}