Asynchronous Processing in Java/JEE/Spring Async Servlets, Async EJBs, Async Spring Beans, Async Web Service Clients, Async Logging.

1. Asynchronous Processing
Java/JEE/Spring
Naresh Chintalcheru

2. Asynchronous Processing
What is Asynchronous Processing ?
A process that executes independently of another
process.
When a request is processed asynchronously, the client
application continues to perform other operations
while it waits for the service request to be filled.

3. Synchronous Processing
4
Client
Browser
1
2
3
5
Server Side Components
[1]100ms + [2]100ms + [3]100ms + [4]100ms + [5]100ms
Client Response time = 500ms

4. Asynchronous Processing
4
Client
Browser
1
2
3
5
Server Side Components
Client Response Time [1] = 100ms
Asynchronous Background Processing Time = 400ms
[2]100ms + [3]100ms + [4]100ms + [5]100ms

5. Asynchronous Processing
The Asynchronous Processing is possible if the given
programming language, runtime and frameworks
supports
Non-Blocking I/O

6. Non-Blocking I/O
What is Non-Blocking I/O ?
Non-Blocking I/O is a form of input/output processing
that permits other processing to continue before the
transmission has finished.

7. Java/JEE
Java 1.4 started the support for Non-Blocking I/O
JEE 6 with partial support with full support in JEE 7

8. Asynchronous EJB 3.0
Web
Service
Client
Browser
Servlet
EJB
DAO
Database
Server Side
@Asynchronous //All methods async
public class AccountBean {
@Asynchronous //This method async
public void updateAccount() {
}
}

9. Asynchronous Servlets 3.0
Web
Service
Client
Browser
Servlet
EJB
DAO
Database
Server Side
@WebServlet(urlPatterns="/MyAsyncServlet", asyncSupported=true)
public class MyAsyncServlet extends HttpServlet {
protected void doGet(Httpreq, HttpServletRes)
{}
}

10. Async Beans in Spring Framework
Web
Service
Client
Browser
Servlet
Bean
DAO
Database
Server Side
@Component
public class AccountBean {
@Async
public void createAccount() {
System.out.println("NEW THREAD " + new Date() + " NEW THREAD");
}
}

11. Asynchronous JavaBean/DAO
Synchronus JDBC Database Calls
User user = userDAO.getByID(userID);
Invoice invoice = invoiceDAO.getByUserID(userID);
PaymentHistory paymentHistory = paymentDAO.getHistoryByuserID(userID);
List<Order> orders = orderDAO.getOpenOrdersByUserID(userID);

12. Asynchronous JavaBean/DAO
Java.util.concurrent APIs
Future Object :
A Future represents the result of an asynchronous computation. Methods are
provided to check if the computation is complete, to wait for its completion,
and to retrieve the result of the computation

13. Asynchronous JavaBean/DAO
Asynchronous JDBC Database Calls
Future<User> futureUser = userDAO.getByID(userID);
Future<Invoice> futureInvoice = invoiceDAO.getByUserID(userID);
Future<PaymentHistory> futurePaymentHistory = paymentDAO.getByuserID(userID);
Future<List<Order>> futureOrders = orderDAO.getOpenOrdersByUserID(userID);
Future<user> futureUser = userDAO.getUserById(userId);
User user = futureUser.get(); //block happens here
user.setCount(user.getCount() + 1);

14. Asynchronous Logging
No one wants Logging framework to be bottleneck
Log4J’s new AsyncLoggers can improve
performance
Log4J AsyncLogger is Insanly Fast

15. Asynchronous Web Services
Invoking a SOAP Web Service Using Asynchronous RequestResponse
Creating the Asynchronous JAX-WS 2.0 Client
Uses the concurrent Future Object

16. Asynchronous REST Service
Invoking a RESTFul Services Asynchronously
Creating the Asynchronous JAX-RS 2.0 Client
The JAX-RS 2.0 client framework supports an asynchronous
API and a callback API

17. Async JDBC Drivers
PostgreSQL Extensions to the JDBC API
Listen / Notify
Listen and Notify provide a simple form of signal or interprocess communication
mechanism for a collection of processes accessing the same PostgreSQL™
database. For more information on notifications consult the main server
documentation. This section only deals with the JDBC specific aspects of
notifications.

18. Asynchronous Processing Issues
x
3
Client
Browser
1
1
2
4
Server Side
What happens if server side failure occurs ?

19. Event-Driven Architecture
Asynchronous + Event-Driven Architecture can
solve the server side failures.
Look at my EDA Presentation on Slideshare.net
“Lie Cheat Steal to build Hyper-Fast Applications using Event-Driven Architecture”

20. Thank You
Thank You