How to solve NullPointerException at mailSender when using some organization as a host - spring

Question

I'm trying to send emails using an organisation mailSender.
Controller
#RequestMapping(value="/forgetPassword", method = RequestMethod.POST, consumes={"application/json"})
public #ResponseBody User forgetPassword(#RequestBody User user) throws Exception {
user=userService.forgetPassword(user, newPassword);
if(user !=null)
{
SendEmail callsendEmail = new SendEmail();
callsendEmail.emailSender(user);
return user;
}
else
{
return user;
}
}
SendEmail
public class SendEmail {
private JavaMailSender mailSender;
private VelocityEngine velocityEngine;
private SimpleMailMessage templateMessage;
public void emailSender(final User user) throws Exception {
MimeMessage mimeMessage = mailSender.createMimeMessage();
MimeMessageHelper message = new MimeMessageHelper(mimeMessage, true);
message.setFrom(templateMessage.getFrom());
message.setTo(user.getEmail());
message.setSubject(templateMessage.getSubject());
Map<String, User> model = new HashMap<String, User>();
model.put("user", user);
/*String text = VelocityEngineUtils.mergeTemplateIntoString(velocityEngine, "org/utility/mailTemplate.vm", model);
message.setText(text, true);*/
if (mailSender != null) {
mailSender.send(mimeMessage);
}
}
public void setVelocityEngine(VelocityEngine velocityEngine) {
this.velocityEngine = velocityEngine;
}
public JavaMailSender getMailSender() {
return mailSender;
}
public void setMailSender(JavaMailSender mailSender) {
this.mailSender = mailSender;
}
public SimpleMailMessage getTemplateMessage() {
return templateMessage;
}
public void setTemplateMessage(SimpleMailMessage templateMessage) {
this.templateMessage = templateMessage;
}
}
Configuration
<bean id="emailSender" class="org.utility.SendEmail">
<property name="mailSender" ref="mailSender" />
<property name="velocityEngine" ref="velocityEngine" />
<property name="templateMessage" ref="templateMessage" />
</bean>
<bean id="mailSender" class="org.springframework.mail.javamail.JavaMailSenderImpl">
<property name="host" value="10.6.12.229" />
<property name="port" value="25" />
</bean>
<bean id="velocityEngine" class="org.springframework.ui.velocity.VelocityEngineFactoryBean">
<property name="velocityProperties">
<value>resource.loader=class class.resource.loader.class=org.apache.velocity.runtime.resource.loader.ClasspathResourceLoader</value>
</property>
</bean>
<bean id="templateMessage" class="org.springframework.mail.SimpleMailMessage">
<property name="from" value="noreply#scrumtracker.com" />
<property name="subject" value="Scrum Tracker Login Details" />
</bean>
Here's the stack trace:
SEVERE: Servlet.service() for servlet [spring] in context with path [/OLPV] threw exception [Request processing failed; nested exception is java.lang.NullPointerException] with root cause
java.lang.NullPointerException
at org.utility.SendEmail.emailSender(SendEmail.java:24)
at org.controller.UserController.forgetPassword(UserController.java:125)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at org.springframework.web.method.support.InvocableHandlerMethod.invoke(InvocableHandlerMethod.java:219)
at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:132)
at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:104)
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandleMethod(RequestMappingHandlerAdapter.java:745)
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:686)
at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:80)
at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:925)
at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:856)
at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:936)
at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:838)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:641)
at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:812)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:722)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
at org.springframework.web.multipart.support.MultipartFilter.doFilterInternal(MultipartFilter.java:119)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:242)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:243)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:201)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:163)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:108)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:556)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:401)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:242)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:267)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:245)
at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:260)
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
I'm getting nullpointer exception on running the above code. Data is passing to the SendEmail class from Controller. Any idea on this?

Answer 1

Set #autowired from calling class (Don't do New) to the mailSend class.
Write #Service in mailSend class.
Directly call the mailSend.Send() method from the calling class.
All prop will be set automatically. No null point exception.
Namaste !

Answer 2

In your Controller class you don't need to instantiante the SendEmail like you do
SendEmail callsendEmail = new SendEmail();
But instead inject it as a spring bean
#Controller
class MyController {
#Autowired
private SendEmail callsendEmail;
#RequestMapping(value="/forgetPassword", method = RequestMethod.POST, consumes={"application/json"})
public #ResponseBody User forgetPassword(#RequestBody User user) throws Exception {
user=userService.forgetPassword(user, newPassword);
if(user !=null)
{
callsendEmail.emailSender(user);
return user;
}
else
{
return user;
}
}
}
If your application context is not configured to autowire beans by annotations, then use a regular setter in the class
#Required
public void setSendEmail( SendEmail sendEmail ) {
this.callsendEmail = sendEmail;
}