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This article will explain based on Maven project. If you don't understand maven, you can refer to the previous article published   Rely on the downloaded Maven website: https://mvnrepository.com/   Struts2   What is struts? A web application framework designed based on mvc pattern is an upgraded version of struts 1, which ...

1, One to many association configuration 1. Association refers to the reference relationship between classes. If class A is associated with class B, the referenced class B will be defined as an attribute of class A. 2. One to many association: For example: order and order item. An order has multiple order items;         ...

1. What kind of data needs to be cached 1. Data rarely modified 2. Less important data, allowing occasional concurrent data 3. Data that will not be accessed concurrently 4. Reference data refers to constant data that provides reference for use. It has a limited number of instances, and its instances are referenced by instances of many othe ...

1, One to many association configuration Database: master table, slave table, associated by foreign key Class: class A{ B b； } class B{ } Example: order and orderItem order entity class package com.sjy.entity; import java.util.HashSet; import java.util.Set; public class Order { // create table t_hibernate_order // ( // order_id i ...

Be careful, there are pits 1.mybatis enables transactions by default. If you add, delete, or modify a transaction, you need to submit the transaction manually. 2. After integration with spring, there is no need to process transactions manually. Related blog posts 1. Use of mybatis MyBatis use 2. mybatis parameter transfer mybatis is t ...

Original website: JPA--SpringBoot -- custom SQL -- Integration / method / how / how / instance / example / actual combat / tutorial -- spring data JPA_ CSDN blog brief introduction explain         When JPA customizes SQL, all additions, deletions and queries are annotated with @ Query, except that the statements inside a ...

1, scope interpretation scope has two values, singleton and prototype single is the default value, which means that the UserDaoImpl class retrieved from the xml is the only one each time, and the class is created when the app object is created //Test code ApplicationContext app = new ClassPathXmlApplicationContext("applicationContext.xml"); u ...

affair Transaction is very important in the project development process. It involves the problem of data consistency, which should not be careless!Transaction management is a necessary technology in enterprise application development to ensure data integrity and consistency. Transaction is to treat a series of actions as an independent unit o ...

Spring 5 declarative transaction control 1. Programming transaction control related objects 1.1 PlatformTransactionManager The PlatformTransactionManager interface is the transaction manager of spring, which provides our common methods of operating transactions. methodexplainTransactionStatus getTransaction(TransactionDefination definat ...

1, Object oriented 1. Object oriented Object Oriented (OO) is also called Object Oriented thought. It is not only a programming thinking, but also a way of thinking. The basic idea is the three characteristics of object-oriented, inheritance, encapsulation and polymorphism. 2. Cumulative sum object Class: is the abstraction of object! ...