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This article focuses on "what is Spring Aop transaction management". Interested friends may wish to have a look at it. The method introduced in this paper is simple, fast and practical. Let's let the editor take you to learn what Spring Aop transaction management is.

When method A calls method B in the same class, if you set a transaction on method B, the transaction of method B will not take effect because method An is not accessed through a proxy object, so transaction enhancement does not take effect. It should be noted, however, that if a transaction is configured on method An and An and B are managed by a transaction manager, method B is still executed in the transaction context of method A.

/ * *

* No transaction is configured for the outer method to verify the scenario when the similar method is called:

* 1. Method B configures the transaction and throws an exception after performing the database operation, and the data will not be rolled back: because the calling transaction in the method does not take effect

* 2. As above, the transaction is rolled back through proxy object access.

, /

Public void pureA_tranB_throw () {

/ / No transaction, transaction commits normally

Db1Op ()

/ / 1. It will not be rolled back because the calling transaction in the method does not take effect.

/ / traB_throw ()

/ / 2. Through the proxy object, the transaction will be rolled back

C1Services c1Services = (C1Services) AopContext.currentProxy ()

C1Services.traB_throw ()

Throw new RuntimeException ("test rollback")

}

@ Transactional (rollbackFor = RuntimeException.class, value = "db1transactionManager")

Public void traB_throw () {

Db1Op ()

Throw new RuntimeException ("test rollback")

}

/ * *

* the outer method configures the transaction to verify the scenario when the similar method is called:

* 1. Method B configures the transaction and throws an exception after performing the database operation. Although method B does not enable transaction enhancement, it belongs to the same transaction manager as the outer transaction and the data will be rolled back.

, /

@ Transactional (rollbackFor = RuntimeException.class, value = "db1transactionManager")

Public void traA_traB_throw () {

/ / if there is an outer transaction, the transaction will be rolled back

Db1Op ()

/ / 1. Rollback, because although the transaction of method B does not fail, the outer layer belongs to the same transaction manager, so the outer transaction controls its rollback

TraB_throw ()

Throw new RuntimeException ("test rollback")

}

Method A calls method B2 in the same class, the transaction manager of method An and B2 is different, transaction is configured on method A, transaction is configured on method B2, exception is executed by B2. If the A method calls the B2 method directly, B2 will not be rolled back, as above, because the transaction enhancement does not take effect, but it can be rolled back through proxy object access.

/ * *

* the outer method configures transactions to verify scenarios of different database operations:

* 1. No rollback, transaction enhancement of B2 method does not take effect, and B2 and outer methods are not a transaction manager, so they will not be affected by outer transactions.

* 2. Rollback, transaction enhancement of B2 method takes effect, execution exception, transaction rollback

, /

@ Transactional (rollbackFor = RuntimeException.class, value = "db1transactionManager")

Public void traA_traB2_throw () {

/ / if there is a transaction, the transaction will be rolled back

Db1Op ()

/ 1. No rollback, transaction enhancement did not take effect

/ / traB2_throw ()

/ / through the proxy object, the transaction will be rolled back

C1Services c1Services = (C1Services) AopContext.currentProxy ()

C1Services.traB2_throw ()

Throw new RuntimeException ("test rollback")

}

@ Transactional (rollbackFor = RuntimeException.class, value = "db2transactionManager")

Public void traB2_throw () {

Db2 ()

Throw new RuntimeException ("test rollback")

}

The A method of C1 class in different classes calls the B method of C2 class, and the B method is called through the instance object of the class. If the B method sets the transaction, because it is accessed through the proxy object, the transaction enhancement will take effect.

The communication behaviors of transactions include:

REQUIRED supports the current transaction and creates a new transaction if the current transaction does not exist. Is the default isolation level for spring transaction management

SUPPORTS supports the current transaction. If the current transaction does not exist, it runs as no transaction.

MANDATORY supports the current transaction, and throws an exception if the current transaction does not exist

REQUIRES_NEW creates a new transaction and suspends the current transaction if it exists

NOT_SUPPORTED runs as no transaction, and suspends the current transaction if the current transaction exists

NEVER runs as no transaction, and throws an exception if the current transaction exists

NESTED if the current transaction exists, it is executed as a nested transaction, and nested transactions are created on special transaction managers. Some JTA providers support nested transaction managers.

At this point, I believe you have a deeper understanding of "what is Spring Aop transaction management". You might as well do it in practice. Here is the website, more related content can enter the relevant channels to inquire, follow us, continue to learn!

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