Attempt to provide a workaround for date rollback issue

git-svn-id: https://svn.apache.org/repos/asf/jakarta/commons/proper/net/branches/JDK_1_5_BRANCH@543998 13f79535-47bb-0310-9956-ffa450edef68

Author: Rory Winston

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

@@ -33,7 +33,7 @@
 import org.apache.commons.net.SocketClient;
 
 /***
- * FTP provides the basic the functionality necessary to implement your
+ * FTP provides basic functionality necessary to implement your
  * own FTP client.  It extends org.apache.commons.net.SocketClient since
  * extending TelnetClient was causing unwanted behavior (like connections
  * that did not time out properly).
@@ -311,8 +311,7 @@ private void __getReply() throws IOException
                 // returning too soon after encountering a naked CR or some other
                 // anomaly.
             }
-            while (!(line.length() >= 4 && line.charAt(3) != '-' &&
-                     Character.isDigit(line.charAt(0))));
+            while ((line.length() >= 4 || line.charAt(3) == '-' || !(line.substring(0,3).matches("\\d{3}"))));
             // This is too strong a condition because of non-conforming ftp
             // servers like ftp.funet.fi which sent 226 as the last line of a
             // 426 multi-line reply in response to ls /.  We relax the condition to

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

@@ -2431,14 +2431,35 @@ public void configure(FTPClientConfig config) {
     public void setListHiddenFiles(boolean listHiddenFiles) {
     	this.__listHiddenFiles = listHiddenFiles;
     }
-
+    
     /**
      * @see #setListHiddenFiles(boolean)
      * @return the current state
      */
     public boolean getListHiddenFiles() {
     	return this.__listHiddenFiles;
     }
+
+    /**
+     * 
+     * @return
+     */
+	public boolean isDateRollbackPermitted() {
+		return __configuration.isDateRollbackPermitted();
+	}
+
+	/**
+	 * Set a boolean flag that specifies whether short date timestamps on the server 
+	 * (i.e. those with no year component) can be "rolled back" by a year if the server
+	 * timestamp is greater than the local timestamp. This is true by default.
+	 *
+	 * @param dateRollbackPermitted false to explicitly prevent date rollback
+	 */
+	public void setDateRollbackPermitted(boolean dateRollbackPermitted) {
+		__configuration.setDateRollbackPermitted(dateRollbackPermitted);
+	}
+    
+    
 }
 
 /* Emacs configuration

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

@@ -192,6 +192,8 @@ public class FTPClientConfig
 	private String shortMonthNames = null;
 	private String serverTimeZoneId = null;
 
+	private boolean dateRollbackPermitted = true;
+	
 
 	/**
 	 * The main constructor for an FTPClientConfig object
@@ -554,5 +556,22 @@ public static Collection getSupportedLanguageCodes() {
 	    return LANGUAGE_CODE_MAP.keySet();
 	}
 
+
+	/**
+	 * getter for the {@link #dateRollbackPermitted} property
+	 * @return
+	 */
+	public boolean isDateRollbackPermitted() {
+		return dateRollbackPermitted;
+	}
+	
+	/**
+	 * @see FTPClient#setDateRollbackPermitted(boolean)
+	 * 
+	 * @param dateRollbackPermitted true/false
+	 */
+	public void setDateRollbackPermitted(boolean dateRollbackPermitted) {
+		this.dateRollbackPermitted = dateRollbackPermitted;
+	}
 
 }

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

@@ -26,6 +26,7 @@
 import java.util.TimeZone;
 
 import org.apache.commons.net.ftp.Configurable;
+import org.apache.commons.net.ftp.FTPClient;
 import org.apache.commons.net.ftp.FTPClientConfig;
 
 /**
@@ -44,6 +45,7 @@ public class FTPTimestampParserImpl implements
 	private SimpleDateFormat defaultDateFormat;
 	private SimpleDateFormat recentDateFormat;
 	private boolean lenientFutureDates = false;
+	private boolean dateRollbackPermitted = true;
 
 
 	/**
@@ -91,7 +93,7 @@ public Calendar parseTimestamp(String timestampStr) throws ParseException {
 			    // slightly in the future to roll back a full year.  (Bug 35181)
 			    now.add(Calendar.DATE, 1);
 			}    
-			if (working.after(now)) {
+			if (working.after(now) && isDateRollbackPermitted()) {
 				working.add(Calendar.YEAR, -1);
 			}
 		} else {
@@ -244,6 +246,8 @@ public void configure(FTPClientConfig config) {
 		setServerTimeZone(config.getServerTimeZoneId());
 
 		this.lenientFutureDates = config.isLenientFutureDates();
+		
+		this.dateRollbackPermitted = config.isDateRollbackPermitted();
 	}
     /**
      * @return Returns the lenientFutureDates.
@@ -257,4 +261,19 @@ boolean isLenientFutureDates() {
     void setLenientFutureDates(boolean lenientFutureDates) {
         this.lenientFutureDates = lenientFutureDates;
     }
+    
+    /**
+     * @returns the {@link #dateRollbackPermitted} property
+     */
+    boolean isDateRollbackPermitted() {
+		return dateRollbackPermitted;
+	}
+    
+    /**
+     * @see FTPClient#setDateRollbackPermitted(boolean)
+     * @param dateRollbackPermitted
+     */
+    void setDateRollbackPermitted(boolean dateRollbackPermitted) {
+		this.dateRollbackPermitted = dateRollbackPermitted;
+	}
 }

src/main/java/org/apache/commons/net/io/CopyStreamException.java

@@ -68,4 +68,12 @@ public IOException getIOException()
     {
         return ioException;
     }
+    
+    /**
+     * Returns the original {@link IOException}
+     */
+    @Override
+    public Throwable getCause() {
+    	return getIOException();
+    }
 }

src/site/xdoc/changes.xml

@@ -23,6 +23,14 @@ limitations under the License.
 
 	<body>
 		<release version="2.0" date="" description="Java 5.0 release">
+			<action dev="rwinston" type="update" issue="NET-159">
+				Add a setDateRollbackPermitted() method to disable rolling 
+				back dates by 1 year when only short date format is 
+				available, and server timstamp is ahead of local.
+			</action>
+			<action dev="rwinston" type="update" issue="NET-153">
+				Add getCause() to CopyStreamException
+			</action>
 			<action dev="rwinston" type="update" issue="NET-155">
 				Change NNTPClient/NewsgroupInfo article counts from int to long
 			</action>

src/test/java/org/apache/commons/net/ftp/parser/FTPTimestampParserImplTest.java

@@ -158,6 +158,49 @@ public void testParseTimestampAcrossTimeZones() {
 	}
 
 
+	public void testParseWithoutDateRollback() {
+		FTPTimestampParserImpl parser = new FTPTimestampParserImpl();
+		
+		// Client calendar
+		Calendar now = Calendar.getInstance();
+		
+		// Server calendar - same TZ, +1 hour drift
+		Calendar working = Calendar.getInstance();
+		working.add(Calendar.HOUR_OF_DAY, 1);
+		
+		// Create a dummy timestamp
+		SimpleDateFormat formatter = new SimpleDateFormat("MMM d HH:mm");
+		String timestamp = formatter.format(working.getTime());
+		
+		Calendar server = null;
+		
+		try {
+			server = parser.parseTimestamp(timestamp);
+		} catch (ParseException e) {
+			e.printStackTrace();
+		}
+		
+		// As the server's clock is (client clock + 1 hour), the date should have rolled back
+		// by a full year
+		assertTrue( server.get(Calendar.YEAR) == now.get(Calendar.YEAR) - 1 );
+		
+		/* Now, we attempt to parse the same timestamp, but explicitly disallow */
+		/* date rollback														*/
+		
+		// Set property directly on parser (normally we would set it via the FTPClientConfig instance)
+		parser.setDateRollbackPermitted(false);
+	
+		try {
+			server = parser.parseTimestamp(timestamp);
+		} catch (ParseException e) {
+			e.printStackTrace();
+		}
+		
+		// The local and remote year value should be equal
+		assertTrue( server.get(Calendar.YEAR) == now.get(Calendar.YEAR) );
+	}
+	
+	
 	public void testParser() {
 		FTPTimestampParserImpl parser = new FTPTimestampParserImpl();
 		try {