spring jpa tutorial

When using spring data JPA in the previous project, when the requirement to delete records was encountered, it was mainly handled using the own delete () method in spring data, which was recently used in the DAO layer using the Delete SQL statement times error, the code is as follows:[Java]View PlainCopy @Query (value = "Delete Parcel,parcel_file,ms_files,t_o

EJB is the Sun's Java EE server-side component model, and the design goal and core application is to deploy distributed applications. With the advantages of Java cross-platform, distributed systems deployed with EJB technology can be limited to specific platforms. EJB (Enterprise JavaBean) is part of the Java EE, which defines a standard for developing component-based enterprise multi-application applications. Features include network service support and core development tools (SDKs). In Java EE

Today we have configured the JPA 0 XML configuration for Springboot, which is finally configured and shared as a learning configuration for springboot and JPA, most of which are XML-based configurations. JPA configuration Reference Web, mainly XML configuration Relax and enjoy the fun of springdata Springboot's Learning Reference

OK, now I'm going to build a project, I want to define a Basedao, and then directly inherit the DAO from other modules directly. This Basedao,basedao has a common approach and a handy way for spring data JPA So create a new Basedao, this basedao should be inherited jparepository,jpaspecificationexecutor because we want to use spring data

Spring-data-jpa -- if one-to-one and others-to-one annotations are used, an error solution will appear during Jackson's json String Conversion, References: Http://blog.csdn.net/remote_roamer/article/details/51330843 Http://blog.csdn.net/xiaodaiye/article/details/51118870 In spring-data-jpa, one-to-one and two-to-on

The premise of this article:two ways to implement a simple dynamic query using spring Data Jpa in SpringbootThe second method in this article implements specification this method only applies to one object for a fixed field query, and the following is overridden by generics:Importjava.util.List;ImportJavax.persistence.criteria.CriteriaBuilder;ImportJavax.persistence.criteria.CriteriaQuery;Importjavax.persis

The project used the SPRING-DATA-JPA, today in writing an update method of the time to report a null pointer, looked at is because an object in the association did not take out, I use GetOne get this object, add a breakpoint to see this object is a Hibernate agent object , not the entity, there is basically no value. Then I switched to FindOne and tried it, and the breakpoint looked at the object that was

Usage of @Query annotations (Spring Data JPA) Reference article: http://Www.tuicool.com/articles/jQJBNv 1. A simple example of using @query annotations @query (value="Select Name,author,price from book B where b.price>?1 and b.price") ListLongPrice1,LongPrice2); 2. Like expression @query (value="Select Name,author,price from book B where b.name like%:name%") List"name") String name); 3using native SQL query

Resources:http://blog.csdn.net/remote_roamer/article/details/51330843http://blog.csdn.net/xiaodaiye/article/details/51118870In Spring-data-jpa, One-to-many and many-to-one annotations were used, and an error occurred while JSON was being serialized.The following solutions have been found through the data access:Annotate the associated fields by adding @jsonmanagedreference to the pojo of the main table:@One

rules defined by the Spring Data JPA method: (1) Simple condition querySimple conditional query: Queries an entity class or collection.In accordance with the specifications of Spring data, the query method begins with a Find | read | Get , and when the query condition is involved, the properties of the condition are connected with the Conditional keyword, note t

The second way to integrate spring and JPA is to get entitymanagerfactory by using Springframe's Localcontainerentitymanagerfactorybean. Change the class reference for the previous fetch entitymanagerfactory: All we need to do is configure persistencexmllocation this property to specify the Meta-inf/persistence.xml inside the classpath. This approach is a powerful way to configure

1. For LOB types that store big data, JPA can only be annotated in Entiry @lob LOBs represent large object data, including BLOBs and CLOB two types, which are used to store large chunks of binary data, slice data, video data, etc., while the latter is used to store long text data, such as the forum's post content, product details, etc. It is noteworthy that: in different databases, large objects corresponding to the field type is not the same, s

Spring-boot official case analysis of the DATA-JPAPackage SAMPLE.DATA.JPA;Import Org.junit.Before;Import Org.junit.Test;Import Org.junit.runner.RunWith;Import org.springframework.beans.factory.annotation.Autowired;Import org.springframework.boot.test.SpringApplicationConfiguration;Import Org.springframework.test.context.ActiveProfiles;Import Org.springframework.test.context.junit4.SpringJUnit4ClassRunner;Import org.springframework.test.context.web.Web

double with a two-bit decimal point behind it.6. @JsonDeserializeThis annotation is used on attributes or setter methods, and can be used to embed our custom code when deserializing, similar to the above @jsonserialize* The JPA namedqueries can be used as follows:1: Use @namedquery on the entity class, as shown in the following example:@NamedQuery (name = "Usermodel.findbyage", query = "Select O from Usermodel o where o.age >=? 1")Note: Use the follo

, and its own modification: optimistic, the meaning of the representative is that most of the scenarios are consistent version. But from the business point of view and ensure strict consistency of data, avoid dirty reading and other issues, the use of the scene needs to be considered. Remember the previous blog simple introduction of the concept of row-level lock, in fact, and optimistic lock is to want to the database level plus lock control concurrency, then when to use optimistic lock, row-le