I'm new to Java and I was trying the JavaMail feature, and it keeps giving me this error when i run the program:
java.lang.NoClassDefFoundError: Could not initialize class
sun.security.ssl.SSLExtension
I ran it on a different project, and it worked fine until I integrated it in a web app. Now the error pops up.
Below is my servlet which gives error.
/*
* To change this license header, choose License Headers in Project Properties.
* To change this template file, choose Tools | Templates
* and open the template in the editor.
*/
import java.io.IOException;
import java.io.PrintWriter;
import java.util.Properties;
import javax.mail.Message;
import javax.mail.MessagingException;
import javax.mail.PasswordAuthentication;
import javax.mail.Session;
import javax.mail.Transport;
import javax.mail.internet.InternetAddress;
import javax.mail.internet.MimeMessage;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
/**
*
* @author User
*/
public class SendMail extends HttpServlet {
/**
* Processes requests for both HTTP <code>GET</code> and <code>POST</code>
* methods.
*
* @param request servlet request
* @param response servlet response
* @throws ServletException if a servlet-specific error occurs
* @throws IOException if an I/O error occurs
*/
protected void processRequest(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
response.setContentType("text/html;charset=UTF-8");
try (PrintWriter out = response.getWriter()) {
/* TODO output your page here. You may use following sample code. */
out.println("<!DOCTYPE html>");
out.println("<html>");
out.println("<head>");
out.println("<title>Servlet SendMail</title>");
out.println("</head>");
out.println("<body>");
out.println("<h1>Servlet SendMail at " + request.getContextPath() + "</h1>");
out.println("</body>");
out.println("</html>");
}
}
// <editor-fold defaultstate="collapsed" desc="HttpServlet methods. Click on the + sign on the left to edit the code.">
/**
* Handles the HTTP <code>GET</code> method.
*
* @param request servlet request
* @param response servlet response
* @throws ServletException if a servlet-specific error occurs
* @throws IOException if an I/O error occurs
*/
@Override
protected void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
processRequest(request, response);
}
/**
* Handles the HTTP <code>POST</code> method.
*
* @param request servlet request
* @param response servlet response
* @throws ServletException if a servlet-specific error occurs
* @throws IOException if an I/O error occurs
*/
@Override
protected void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
processRequest(request, response);
String to=request.getParameter("to");
String subject=request.getParameter("subject");
String msg=request.getParameter("msg");
send();
System.out.println("message has been sent successfully");
}
/**
* Returns a short description of the servlet.
*
* @return a String containing servlet description
*/
@Override
public String getServletInfo() {
return "Short description";
}// </editor-fold>
public void send(){
String to = "[email protected]";//change accordingly
String from = "[email protected]";
String host = "smtp.gmail.com";//or IP address
//Get the session object
Properties properties = System.getProperties();
properties.setProperty("mail.smtp.host", "smtp.gmail.com");
properties.setProperty("mail.smtp.port", "587");
properties.put("mail.smtp.auth", "true");
properties.put("mail.smtp.starttls.enable", "true");
Session session = Session.getInstance(properties,new javax.mail.Authenticator() {
protected PasswordAuthentication getPasswordAuthentication() {
return new PasswordAuthentication(from,"123");
}
});
//compose the message
try{
MimeMessage message = new MimeMessage(session);
message.setFrom(new InternetAddress(from));
message.addRecipient(Message.RecipientType.TO,new InternetAddress(to));
message.setSubject("Ping");
message.setText("Hello, this is example of sending email ");
// Send message
Transport.send(message);
System.out.println("message sent successfully....");
}catch (MessagingException mex) {mex.printStackTrace();}
}
}
Below is the Java file I used
import java.util.*;
import javax.mail.*;
import javax.mail.internet.*;
import javax.activation.*;
public class Mailer {
public static void main(String[] args){
String to = "[email protected]";//change accordingly
String from = "[email protected]";
String host = "localhost";//or IP address
//Get the session object
Properties properties = System.getProperties();
properties.setProperty("mail.smtp.host", "smtp.gmail.com");
properties.setProperty("mail.smtp.port", "587");
properties.put("mail.smtp.auth", "true");
properties.put("mail.smtp.starttls.enable", "true");
Session session = Session.getInstance(properties,new javax.mail.Authenticator() {
protected PasswordAuthentication getPasswordAuthentication() {
return new PasswordAuthentication(from,"123");
}
});
//compose the message
try{
MimeMessage message = new MimeMessage(session);
message.setFrom(new InternetAddress(from));
message.addRecipient(Message.RecipientType.TO,new InternetAddress(to));
message.setSubject("Ping");
message.setText("Hello, this is example of sending email ");
// Send message
Transport.send(message);
System.out.println("message sent successfully....");
}catch (MessagingException mex) {mex.printStackTrace();}
}
}
Error Message
java.lang.NoClassDefFoundError: Could not initialize class sun.security.ssl.SSLExtension
at sun.security.ssl.SSLConfiguration.getEnabledExtensions(SSLConfiguration.java:380)
at sun.security.ssl.ClientHello$ClientHelloKickstartProducer.produce(ClientHello.java:562)
at sun.security.ssl.SSLHandshake.kickstart(SSLHandshake.java:509)
at sun.security.ssl.ClientHandshakeContext.kickstart(ClientHandshakeContext.java:110)
at sun.security.ssl.TransportContext.kickstart(TransportContext.java:233)
at sun.security.ssl.SSLSocketImpl.startHandshake(SSLSocketImpl.java:394)
at sun.security.ssl.SSLSocketImpl.startHandshake(SSLSocketImpl.java:373)
at com.sun.mail.util.SocketFetcher.configureSSLSocket(SocketFetcher.java:602)
at com.sun.mail.util.SocketFetcher.createSocket(SocketFetcher.java:376)
at com.sun.mail.util.SocketFetcher.getSocket(SocketFetcher.java:193)
at com.sun.mail.smtp.SMTPTransport.openServer(SMTPTransport.java:2151)
at com.sun.mail.smtp.SMTPTransport.protocolConnect(SMTPTransport.java:716)
at javax.mail.Service.connect(Service.java:364)
at javax.mail.Service.connect(Service.java:222)
at javax.mail.Service.connect(Service.java:171)
at javax.mail.Transport.send0(Transport.java:230)
at javax.mail.Transport.send(Transport.java:100)
at SendMail.send(SendMail.java:127)
at SendMail.doPost(SendMail.java:87)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:665)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:750)
at org.apache.catalina.core.StandardWrapper.service(StandardWrapper.java:1540)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:217)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:119)
at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:611)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:550)
at com.sun.enterprise.web.WebPipeline.invoke(WebPipeline.java:75)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:114)
at org.apache.catalina.connector.CoyoteAdapter.doService(CoyoteAdapter.java:332)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:199)
at com.sun.enterprise.v3.services.impl.ContainerMapper$HttpHandlerCallable.call(ContainerMapper.java:439)
at com.sun.enterprise.v3.services.impl.ContainerMapper.service(ContainerMapper.java:144)
at org.glassfish.grizzly.http.server.HttpHandler.runService(HttpHandler.java:182)
at org.glassfish.grizzly.http.server.HttpHandler.doHandle(HttpHandler.java:156)
at org.glassfish.grizzly.http.server.HttpServerFilter.handleRead(HttpServerFilter.java:218)
at org.glassfish.grizzly.filterchain.ExecutorResolver$9.execute(ExecutorResolver.java:95)
at org.glassfish.grizzly.filterchain.DefaultFilterChain.executeFilter(DefaultFilterChain.java:260)
at org.glassfish.grizzly.filterchain.DefaultFilterChain.executeChainPart(DefaultFilterChain.java:177)
at org.glassfish.grizzly.filterchain.DefaultFilterChain.execute(DefaultFilterChain.java:109)
at org.glassfish.grizzly.filterchain.DefaultFilterChain.process(DefaultFilterChain.java:88)
at org.glassfish.grizzly.ProcessorExecutor.execute(ProcessorExecutor.java:53)
at org.glassfish.grizzly.nio.transport.TCPNIOTransport.fireIOEvent(TCPNIOTransport.java:515)
at org.glassfish.grizzly.strategies.AbstractIOStrategy.fireIOEvent(AbstractIOStrategy.java:89)
at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy.run0(WorkerThreadIOStrategy.java:94)
at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy.access$100(WorkerThreadIOStrategy.java:33)
at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy$WorkerThreadRunnable.run(WorkerThreadIOStrategy.java:114)
at org.glassfish.grizzly.threadpool.AbstractThreadPool$Worker.doWork(AbstractThreadPool.java:569)
at org.glassfish.grizzly.threadpool.AbstractThreadPool$Worker.run(AbstractThreadPool.java:549)
at java.lang.Thread.run(Thread.java:748)
When I try to link the Java file with the servlet it gives the same error.
question from:
https://stackoverflow.com/questions/65641288/could-not-initialize 
