First Move Sending email ail block to seperate method. I just cut and pasted your code ..
public static void sendEmail() {
String to = "abcde@gmail.com";// change accordingly
final String user = "vwxyz@gmail.com";// change accordingly
final String password = "xxxxxxx";// change accordingly
// final String d_port = "465";
// 1) get the session object
// java.security.Security.addProvider(new com.sun.net.ssl.internal.ssl.Provider());
Properties props = new Properties();
props.put("mail.smtp.host", "smtp.gmail.com");
props.put("mail.smtp.socketFactory.port", "465");
props.put("mail.smtp.socketFactory.class", "javax.net.ssl.SSLSocketFactory");
props.put("mail.smtp.auth", "true");
props.put("mail.smtp.port", "465");
Session session = Session.getDefaultInstance(props, new javax.mail.Authenticator() {
@Override
protected PasswordAuthentication getPasswordAuthentication() {
return new PasswordAuthentication(user, password);
}
});
// 2) compose message
try {
MimeMessage message = new MimeMessage(session);
message.setFrom(new InternetAddress(user));
message.addRecipient(Message.RecipientType.TO, new InternetAddress(to));
message.setSubject("Message Alert! Changes made to your file");
// 3) create MimeBodyPart object and set your message text
BodyPart messageBodyPart1 = new MimeBodyPart();
messageBodyPart1.setText("This is message body");
// 4) create new MimeBodyPart object and set DataHandler object to this object
MimeBodyPart messageBodyPart2 = new MimeBodyPart();
String filename = "D://abc.txt";// change accordingly
DataSource source = new FileDataSource(filename);
messageBodyPart2.setDataHandler(new DataHandler(source));
messageBodyPart2.setFileName(filename);
// 5) create Multipart object and add MimeBodyPart objects to this object
Multipart multipart = new MimeMultipart();
multipart.addBodyPart(messageBodyPart1);
multipart.addBodyPart(messageBodyPart2);
// 6) set the multiplart object to the message object
message.setContent(multipart);
// 7) send message
Transport.send(message);
System.out.println("message sent....");
}
catch (MessagingException ex) {
System.out.println(ex);
}
}
Then add boolean to mark changes in main like.. Note isFileChanged used to send email the changes captured.
public static void main(String[] args) throws Exception {
FileReader fr = new FileReader("D:/test.txt");
BufferedReader br = new BufferedReader(fr);
boolean isFileChanged = false;
while (true) {
String line = br.readLine();
if (line == null) {
if (isFileChanged){
isFileChanged = false;
sendEmail();
}
Thread.sleep(1 * 1000);
}
else {
isFileChanged = true;
byte[] y = line.getBytes();
File g = new File("D:/abc.txt");
try (OutputStream f = new FileOutputStream(g, true)) {
f.write(y);
}
}
}
}