1. Spring Transaction & Spring AOP
ศิรส สุภาวิตา
@siros_s

2. Agenda: Spring Transaction
Why Spring Transaction
Transaction Manager
Declarative Transaction with Annotation
@Transactional
Propagation
Exception Handling

3. Why Spring Transaction?
Uniform API
Transactional resource synchronization
On and off server
Declarative Transaction

4. What about JTA? Require J(2)EE container (server)
Require EJB for declarative transaction
Necessary for distributed transaction

5. Uniform API
Application
Spring Transaction
JDBC
ORM
JCA
JTA

6. Transactional Resource Sync
Spring Transaction

7. On and Off Server Spring Spring Spring Servlet Container J(2)EE
Java

8. Declarative TransactionB C
Begin
Commit D
Begin
Commit D B C

9. Declarative Transaction (cont.)
Transaction Demarcation
Transaction logic is NOT the main business logic
Reuse business logic with different transaction logic
Programmatic transaction demarcation is NOT the answer

10. Transactional Resource
Transaction Manager
Transactional Resource
Transaction Manager

11. Transaction Annotation
Use annotation to declare transaction scope
Require just one line of config in XML

12. Example: MyService

13. Example: Transactional MyService

14. Example: Detailed MyService

15. Propagation Define how transaction manager handles transaction
SUPPORTS
NOT_SUPPORTED
REQUIRED
REQUIRES_NEW
MANDATORY
NEVER
NESTED

16. Example: Propagation A B C D REQUIRED SUPPORTS REQUIRED MANDAROTY
REQUIRES_NEW
NEVER A B C D
REQUIRES_NEW

17. Exception Handling Default behavior
Rollback for unchecked exception
No rollback for checked exception
Can be changed properties
rollbackFor
rollbackForClassname
noRollbackFor
noRollbackForClassname

18. Example: Exception Handling

19. Wait!! There is a better way!!
Q & A

20. Agenda: Spring AOP Problems of existing approach AOP Definition
AOP Proxy
Spring AOP
Spring Transaction with AOP

21. Problems??
Transaction policy is still defined locally on each class rather than globally across all classes.
Modularity & Reusability
Scattering & Tangling
Even a medium sized application has multiple “concerns”.

22. Example of Transaction Policy
All top level service operations must begin a new transaction (REQUIRES_NEW).
Lower level service operations must operate under an existing transaction (MANDATORY).
Data access operation should operate under a transaction (REQUIRES).
The problem is that policies or concerns are usually applied based on neither class nor class hierarchy. They are mostly random.

23. Scattering obj.lastModified = new Date();
Customer cust = new Customer(); …
cust.lastModified = new Date();
saveCustomer(cust);
Invoice inv = new Invoice(); …
inv.lastModified = new Date();
saveInvoice(inv);
Course crs = new Course(); …
crs.lastModified = new Date();
saveCourse(crs);

24. Scattering: Modified obj.lastModifiedBy = currentUser();
obj.lastModified = new Date();
Customer cust = new Customer(); …
cust.lastModifiedBy = currentUser();
cust.lastModified = new Date();
saveCustomer(cust);
Invoice inv = new Invoice(); …
inv.lastModifiedBy = currentUser();
inv.lastModified = new Date();
saveInvoice(inv);
Course crs = new Course(); …
crs.lastModifiedBy = currentUser();
crs.lastModified = new Date();
saveCourse(crs);

25. Tangling obj.lastModified = new Date(); Course crs = new Course(); …
saveCourse(crs);
logger.log(“Start operation”);
logger.log(“Start operation”);
tx = new Transaction();
tx.begin();
Course crs = new Course();
crs.id = generateUUID(); …
crs.lastModified = new Date();
saveCourse(crs);
tx.commit();
obj.id = generateUUID();
tx = new Transaction();
tx.begin(); …
tx.commit();

26. Aspect-Oriented Programming
Concerns are designed and implemented independently
During build time or runtime, concerns are compiled into full functioned application. This process is called “weaving”.

27. AOP Definition
Aspect
Join Point
Pointcut
Advice

28. Join Point public void createCustomer() { x
Customer cust = new Customer(); …
saveCustomer(cust); }

29. Pointcut public void createCustomer() { x
Customer cust = new Customer(); …
saveCustomer(cust); }

30. Advice public void createCustomer() { logger.log(“Start create…”);
Customer cust = new Customer();
cust.id = generateUUID(); …
cust.lastModified = new Date();
saveCustomer(cust); }

31. AOP Proxy
Caller
Target Object
Advice
Proxy
Advice
Advice

32. Spring AOP

33. Supported Pointcuts
execution
within
this
target
args

34. execution
execution(<modifier> <return-type> <declaring-type> <method-name> (<param>) <throws>)
execution(* *(..))
execution(public void set*(..))
execution(public * com.spring66.service.*.*(..))
execution(public * com.spring66.service..*.*(..))

35. within
within(com.spring66.service.*)
within(com.spring66.service..*)

36. Advice
before
after
after-returning
after-throwing
around

37. Spring Transaction with AOP

38. Is that all?
Q & A