Shulou(Shulou.com)06/02 Report--

Editor to share with you how the spring jpa audit function to customize the fill field, I hope you will gain something after reading this article, let's discuss it together!

Custom populated fields for spring jpa audit function

Spring data jpa implements the audit function through annotations such as @ CreateBy (automatically populating some fields when new or modified), but it is not satisfied when we have multiple fields that need to be populated, so we need to implement the relevant interfaces to populate automatically.

There are two ways.

One is to implement the auditable interface, but this will inexplicably add a lot of setter getter methods to the entity class, which will interfere with serialization, so it is not recommended.

What I recommend is the second way to rewrite Listener

Concrete steps

Enable the audit function in the configration class

@ SpringBootApplication@EnableJpaAuditingpublic class Config () {}

Implement the entity generic inheritance class to specify a custom listener

@ EntityListeners ({CustomAuditingListener.class}) public class Base {private Long id; private Long creator; private String creatorName; private Long modifier; private String modifierName;... Omit setter getter}

To implement a custom listener, there are two core interfaces @ PrePersist and @ PreUpdate, the first is the saved front method (new and updated), and the second is the updated front method through which you can populate yourself.

@ Configurablepublic class CustomAuditingListener implements ConfigurableObject {public AuditListener () {} @ Autowired private AuditHandler auditHandler; @ PrePersist private void prePersist (Object obj) {auditHandler.prePersist (obj);} @ PreUpdate private void preUpdate (Object obj) {auditHandler.preUpdate (obj);}}

Implement custom AuditHandler

@ Componentpublic class CustomAuditHandler implements AuditHandler {@ Override public void prePersist (Object obj) {if (obj instanceof Base) {Base ae = (Base) obj; if (ae.getId () = = null) {this.markForCreate (ae) }} @ Override public void preUpdate (Object obj) {if (obj instanceof Base) {Base ae = (Base) obj; this.markForUpdate (ae);}} public void markForCreate (Base be) {ae.setCreator ("self-acquired user id"); ae.setCreatorName ("self-acquired user name") } public void markForUpdate (Base ae) {ae.setModifier ("self-acquired user id"); ae.setModifierName ("self-acquired user name");}} * / enable Spring Data JPA audit function

Suddenly found that Spring Data JPA has such a function, English is Auditing

JPA Audit description

In spring jpa, annotations on fields or methods are supported: @ CreatedDate, @ CreatedBy,

@ LastModifiedDate, @ LastModifiedBy, literally, you can clearly understand the usefulness of these annotations.

@ CreatedDate: indicates that this field is the creation time field, and the value will be set when the entity is insert.

@ CreatedBy: indicates that the field is the creator, and the value will be set when the entity is insert

The same goes for @ LastModifiedDate and @ LastModifiedBy.

How to use the audit function

First of all, declare that the entity class needs to be annotated with @ EntityListeners (AuditingEntityListener.class), followed by the annotation EnableJpaAuditing in the application startup class, and @ CreatedDate, @ CreatedBy, @ LastModifiedDate, @ LastModifiedBy and other annotations on the required fields.

At this point, when the jpa.save method is called, the time field is automatically set and inserted into the database, but CreatedBy and LastModifiedBy are not assigned because you need to implement the AuditorAware interface to return the value you need to insert.

1. Write AuditorAware/** * snooping * @ CreatedBy * @ LastModifiedBy * automatically inject username * / @ Configurationpublic class UserAuditorAware implements AuditorAware {@ Override public Optional getCurrentAuditor () {/ / TODO: take the real user return Optional.of ("admin") according to the actual situation;}} 2. Declare @ EntityListeners and the corresponding annotations in the entity class

Considering that all entities need to be declared, write it in BaseEntityModel

@ MappedSuperclass@EntityListeners (AuditingEntityListener.class) public class BaseEntityModel implements Serializable {/ * / private static final long serialVersionUID =-6163675075289529459L; @ JsonIgnore String entityName = this.getClass () .getSimpleName (); @ CreatedBy String createdBy; @ LastModifiedBy String modifiedBy; / * entity creation time * / @ Temporal (TemporalType.TIMESTAMP) @ CreatedDate protected Date dateCreated = new Date () / * * entity modification time * / @ Temporal (TemporalType.TIMESTAMP) @ LastModifiedDate protected Date dateModified = new Date (); # omit getter setter} 3. Enable audit @ EnableJpaAuditing@SpringBootApplication@EnableJpaAuditingpublic class Application {public static void main (String [] args) throws Exception {SpringApplication.run (Application .clas s, args) in Application; if it is not automatically identified in the test, it may be a problem with the package path. Declare bean manually * @ return * / @ Bean public UserAuditorAware setUserAuditorAware () {return new UserAuditorAware ();}}

After testing, if multiple fields above your entity class use annotations like @ CreatedBy, only one will take effect, that is, it will only be called once in a request.

After reading this article, I believe you have a certain understanding of "spring jpa audit function how to customize the filled fields". If you want to know more about it, you are welcome to follow the industry information channel. Thank you for reading!

Welcome to subscribe "Shulou Technology Information " to get latest news, interesting things and hot topics in the IT industry, and controls the hottest and latest Internet news, technology news and IT industry trends.