Preface:
September last year, my colleagues and I at the time geeks bought Ding Xuefeng Spring family bucket of learning, the curriculum is divided into 16 chapters in total, I have learned the most part, are recorded in a notebook before, today I want to record on the Blog, Share more knowledge to those in need of help, I will be the number of chapters as the content of the article, the original course speak in more detail, I am here to do a summary on some specific points.
.Spring of a transaction abstraction
Consistent transaction model
- JDBC/Hibernate/myBatis
- Dtsourche / Jria
Transaction abstraction of core interfaces
PlatformTransactionManager
- DataSourceTransactionManager
- HibernateTransactionManager
- JtaTransactionManager
TransactionDefinition
- Propagation
- Islation
- Timeout
- Read-only status
Transaction propagation characteristics
| Transmissible | value | description |
| PROPAGATION_REQUIDED | 0 | We have to use the current transaction, not just with the new |
| PROPAGATION_SUPPORTS | 1 | Transaction optional, not required |
| PROPAGATION_MANDATORY | 2 | Current affairs must be, otherwise Throws |
| PROPAGATION_REQUIRES_NEW | 3 | Whether or not there is a transaction, all from a new transaction |
| PROPAGATION_NOT_SUPPORTED | 4 | It does not support transactions, run by a non-transactional way |
| PROPAGATION_NEVER | 5 | It does not support transactions, if the transaction is Throws |
| PROPAGATION_NESTED | 6 | There are currently Affairs renewed a transaction in the current transaction |
Transaction isolation characteristics
| Isolation | value | Dirty read | Non-repeatable read | Magic Reading |
| ISOLATION_READ_UNCOMMITTED | 1 | yes | yes | yes |
| ISOLATION_READ_COMMITTED | 2 | no | yes | yes |
| ISOLATION_REPEATABLE_READ | 3 | no | no | yes |
| ISOLATION_SERIALIZABLE | 4 | no | no | no |
Programmatic transaction
TransactionTemplate
- TransactionCallback
- TransactionCallbackWithoutResult
PlatformTransactionManager
- Can be defined incoming TransactionDefinition
Declarative transaction
https://www.cnblogs.com/ooo0/p/11029629.html
Annotation-based configuration
Notes affairs open way:
- @EnableTransactionManagement
- <tx:annotation-driven/>
Some configuration
- proxy target class
- model
- order
@Transactional
- transactionManager
- propagation
- isolation
- timeout
- readOnly
- How to determine the rollback
Two. Spring's JDBC abstraction abnormal
Spring abnormal conversion into a data manipulation will DataAccessException
Either use data access, will use the same exception
Spring is understanding how those error codes?
- By SQLErrotCodeSQLExceptionTranslator parse error code
ErrorCode defined
- org/springframework/jdbc/support/sql-error-codes.xml
- sql-error-codes.xml under Classpath
SpringBoot custom error code
Three. SpringBoot common comment
Refer to: https://blog.csdn.net/tangthh123/article/details/104092510
Four. Actuator
| URL | effect |
| /actuator/health | health examination |
| /actuator/beans | View all Bean container |
| /actuator/mapping | View Web URL mapping |
| /actuator/env | View Environmental Information |
Ban all Endpoint
application.properties configuration parameters or application.yml
management.endpoints.web.exposure.include=*V. multiple data sources. Sub-library sub-table. Relations separate read and write
1. Several common
- The system needs to access several different databases, this time can be configured both data sources
- The system requires access to the primary library and the library with a library of backup, that is, to use a separate read and write time, a main library, both a standby database, the data source configured individually, write separation
- The system requires access to a database as a set of sub-library sub-table (vertical split, horizontal split), try to use database middleware.
Nature VI. Affairs
The declarative nature of the transaction by Spring AOP is to enhance the functionality of the class.
The nature Spring AOP is a proxy for the class to do
- Call appears in its own way, eh, it is the actual use of the enhanced proxy class
Problem Solution:
- The method of the proxy class after the visit enhanced, rather than direct access to its own method
VII. Slow logging configuration
Alibaba launched a number of database connection pool Description:
System Configuration Properties
- druid.stat.logSlowSql=true
- druid.stat.slowSqlMillis=3000
SpringBoot
- spring.datasource.druid.filter.stat.enabled=true
- spring.datasource.druid,filter.stat.log-slow-sql=true
- spring.datasource.druid.filter.stat.slow-sql-millis=3000
