copy 'springy' branch to heritrix3

commons/src/main/java/org/archive/net/ClientFTP.java

@@ -0,0 +1,136 @@
+/* ClientFTP.java
+ *
+ * $Id$
+ *
+ * Created on Jun 5, 2003
+ *
+ * Copyright (C) 2003 Internet Archive.
+ *
+ * This file is part of the Heritrix web crawler (crawler.archive.org).
+ *
+ * Heritrix is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser Public License as published by
+ * the Free Software Foundation; either version 2.1 of the License, or
+ * any later version.
+ *
+ * Heritrix is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser Public License
+ * along with Heritrix; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+package org.archive.net;
+
+
+import java.io.IOException;
+import java.net.Socket;
+
+import org.apache.commons.net.ftp.FTPClient;
+import org.apache.commons.net.ftp.FTPReply;
+
+
+/**
+ * Client for FTP operations.  This class is necessary only because the
+ * {@link #_openDataConnection_(int, String)} method is protected in 
+ * the superclass, and we need to call it directly to handle directory
+ * listings.  (The code that provides directory listings in the 
+ * superclass doesn't scale:  It reads the entire directory into
+ * an in-memory list).
+ * 
+ * <p>Additionally, "strict" methods are provided for the other operations
+ * we use.  Maddeningly, the superclass never raises exceptions.  If an 
+ * FTP operation fails, then the superclass methods generally return false.
+ * A developer then needs to check the {@link FTP#getReplyCode()}
+ * method to see what actually went wrong.  The "strict" methods provided
+ * by this class invoke the superclass method, check if the success flag
+ * is false, and then raise an {@link FTPException} with the value of
+ * {@link FTP#getReplyCode()}.
+ *
+ * @author pjack
+ */
+public class ClientFTP extends FTPClient {
+    
+    
+    /**
+     * Constructs a new <code>ClientFTP</code>.
+     */
+    public ClientFTP() {
+    }
+    
+
+    /**
+     * Connects to the FTP server at the given host and port.
+     * 
+     * @param host    the host of the FTP server to connect to
+     * @param port    the port the FTP server listens on
+     * @throws IOException  if the connection cannot be made due to IO error
+     * @throws FTPException  if the server refuses the connection
+     */
+    public void connectStrict(String host, int port) throws IOException {
+        this.connect(host, port);
+        int reply = this.getReplyCode();
+        if (!FTPReply.isPositiveCompletion(reply)) {
+            throw new FTPException(reply);
+        }
+    }
+
+    
+    /**
+     * Login to the FTP server with the given username and password.
+     * 
+     * @param user   the username to login under
+     * @param pass   the password to use
+     * @throws IOException   if a network error occurs
+     * @throws FTPException  if the login is rejected by the server
+     * @throws org.apache.commons.net.ftp.FTPConnectionClosedException   
+     *   if the FTP server prematurely closes the connection (for 
+     *   instance, if the client was idle for too long)
+     */
+    public void loginStrict(String user, String pass) throws IOException {
+        boolean r = this.login(user, pass);
+        if (!r) {
+            throw new FTPException(this.getReplyCode());
+        }
+    }
+
+    
+    /**
+     * Tells the FTP server to send binary files.
+     *
+     * @throws IOException   if a network error occurs
+     * @throws FTPException  if the server rejects the command
+     * @throws org.apache.commons.net.ftp.FTPConnectionClosedException   
+     *   if the FTP server prematurely closes the connection (for 
+     *   instance, if the client was idle for too long)
+     */
+    public void setBinary() throws IOException {
+        boolean r = super.setFileType(BINARY_FILE_TYPE);
+        if (!r) {
+            throw new FTPException(getReplyCode());
+        }
+    }
+
+
+    /**
+     * Opens a data connection. 
+     * 
+     * @param command  the data command (eg, RETR or LIST)
+     * @param path     the path of the file to retrieve
+     * @return  the socket to read data from
+     * @throws  IOException  if a network error occurs
+     * @throws  FTPException  if a protocol error occurs
+     */
+    public Socket openDataConnection(int command, String path)
+    throws IOException {
+        Socket socket = _openDataConnection_(command, path);
+        if (socket == null) {
+            throw new FTPException(this.getReplyCode());
+        }
+        return socket;
+    }
+
+    
+}