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Teddy Zugana
Teddy Zugana

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Java FTPS disabling Certificate Check , FOR FIX FTP SSL certificate expired exception

#java #sftp

1)the encryption of the FTPS server will be either TLS explicit encryption or TLS explicit encryption.Use the constructor arg for FTPS accordingly. like

FTPSClient ftpClient = new FTPSClient(false);
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2)if your FTPS server security certificate has expired, disable the check from client by

ftpClient.setTrustManager(new X509TrustManager() { @Override public X509Certificate[] getAcceptedIssuers() { return null; } @Override public void checkClientTrusted(X509Certificate[] certs, String authType) { } @Override public void checkServerTrusted(X509Certificate[] certs, String authType) { } });
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3)enable file transfer between server and client using this method

ftpClient.enterLocalPassiveMode();
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4)use the right port number. Usually for explicit encryption it is 21 and for implicit it is 990

The above four are the common configs required to establish a connection. The end snippet looks something like this

 FTPSClient ftpClient = new FTPSClient(false); ftpClient.setTrustManager(new X509TrustManager() { @Override public X509Certificate[] getAcceptedIssuers() { return null; } @Override public void checkClientTrusted(X509Certificate[] certs, String authType) { } @Override public void checkServerTrusted(X509Certificate[] certs, String authType) { } }); ftpClient.connect("ftps.mydomain.com",21); boolean res = ftpClient.login("username", "password"); if(!res) throw new Exception("unable to connect to ftps"); int reply=ftpClient.getReplyCode(); if(FTPReply.isPositiveCompletion(reply)){ ftpClient.enterLocalPassiveMode(); FTPFile[] ftpFiles = ftpClient.listFiles("/folder/subfolder"); System.out.println("complete "+reply+" "+ftpFiles.length); for(FTPFile x: ftpFiles){ System.out.println(x.getName()); } ftpClient.retrieveFile("/folder/subfolder/file.tsv",new FileOutputStream(new File("C:\\Users\\myname\\Desktop\\out.csv"))); }else{ throw new RuntimeException("unable to get valid reply from ftp server. Reply code is "+reply); }
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