Erro 500 ao enviar o email

Olá pessoa estou desenvolvendo um sistema, e para recuperar senha o cliente vai na opção recuperar senha na qual será solicitado o email dele que será verificado se já é cadastrado no sistema… Após a verificação ser feita e retornar true tem que ser enviado para o cliente o email com o link para o cliente acessar e trocar a senha. Na parte de validação do email esta funcionando corretamente, mas na parte que tem que enviar o email esta dando erro…

O que aparece no navegador…
Type Exception Report

Message Error instantiating servlet class [servlet.VerificaEmailServlet]

Description The server encountered an unexpected condition that prevented it from fulfilling the request.

Exception

javax.servlet.ServletException: Error instantiating servlet class [servlet.VerificaEmailServlet] org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:475) org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:81) org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:651) org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:342) org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:500) org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66) org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:754) org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1376) org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1135) java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:635) org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) java.base/java.lang.Thread.run(Thread.java:844)

Root Cause

java.lang.InstantiationException java.base/jdk.internal.reflect.InstantiationExceptionConstructorAccessorImpl.newInstance(InstantiationExceptionConstructorAccessorImpl.java:48) java.base/java.lang.reflect.Constructor.newInstance(Constructor.java:488) org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:475) org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:81) org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:651) org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:342) org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:500) org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66) org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:754) org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1376) org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1135) java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:635) org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) java.base/java.lang.Thread.run(Thread.java:844)

Note The full stack trace of the root cause is available in the server logs.

No console…

GRAVE: Allocate exception for servlet [servlet.VerificaEmailServlet]
java.lang.InstantiationException
at java.base/jdk.internal.reflect.InstantiationExceptionConstructorAccessorImpl.newInstance(InstantiationExceptionConstructorAccessorImpl.java:48)
at java.base/java.lang.reflect.Constructor.newInstance(Constructor.java:488)
at org.apache.catalina.core.DefaultInstanceManager.newInstance(DefaultInstanceManager.java:120)
at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:1041)
at org.apache.catalina.core.StandardWrapper.allocate(StandardWrapper.java:770)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:133)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:475)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:140)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:81)
at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:651)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:87)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:342)
at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:500)
at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66)
at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:754)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1376)
at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)
at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1135)
at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:635)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.base/java.lang.Thread.run(Thread.java:844)

Como esta o código na servlet :

	request.setAttribute("msg", "Email, enviado com sucesso!\n "
							+ "Por favor verificar caixa de ENTRADA ou de SPAM de seu email");
			
					DaoEmail daoEmail = new DaoEmail(email);
					daoEmail.recuperarSenha();
				

Erro resolvido por que a classe da servlet estava como private, foi só mudar para public…

Agora aparece o erro
jGRAVE: Allocate exception for servlet [servlet.VerificaEmailServlet]
java.lang.ClassNotFoundException: javax.mail.Authenticator
at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1275)
at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1104)
at servlet.VerificaEmailServlet.(VerificaEmailServlet.java:21)
at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
at java.base/jdk.internal.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.base/java.lang.reflect.Constructor.newInstance(Constructor.java:488)
at org.apache.catalina.core.DefaultInstanceManager.newInstance(DefaultInstanceManager.java:120)
at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:1041)
at org.apache.catalina.core.StandardWrapper.allocate(StandardWrapper.java:770)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:133)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:475)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:140)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:81)
at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:651)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:87)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:342)
at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:500)
at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66)
at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:754)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1376)
at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)
at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1135)
at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:635)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.base/java.lang.Thread.run(Thread.java:844)

Esse erro esta ocorrendo quando eu chamo uma classe para fazer um envio de email, aí o erro aparece.