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Simple reusable GMailJava class for sending Aysnc emails via Gmail

Simple reusable GMailJava class for sending Aysnc emails. Copy the class, change the username/password and use it in your next project. 
   Step 1: Add dependencies to your maven project
<!-- mail --> <dependency> <groupId>javax.mail</groupId> <artifactId>mail</artifactId> <version>1.4</version> </dependency> <!-- Apache Commons Validator --> <dependency> <groupId>commons-validator</groupId> <artifactId>commons-validator</artifactId> <version>1.4.0</version> </dependency> Step 2: Copy to your project & set username/password code: Note: Enable pop, IMAP inside GMail --> Settings --> Forwarding and POP / IMAP

    Sample code

      EmailService emailService = EmailService.getInstance();
      emailService.sendEmail("<toemail>", "<subject>", "<body>");

    Design Decisions
     No interface is define to keep simpler eco-system, feel free to add yours if required and refactor code accordingly
     Pattern's & Technique's used - Singleton, Command, Async, Inner class
Also you can clone it on github


Anonymous said…
In your emailservice class, u are calling shutdown instead of finalize. why
ExecutorService needs to shutdown when EmailService is no longer required this can happen when Web-Application is undeployed or App is terminated and if this not done it will leak out "Threads".

So extra shutdown() method is there incase developer decides to use it in ServletContextListener.contextDestroyed()

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