带有 package-info.java 的 GenericGenerator答案

【问题标题】：GenericGenerator with package-info.java带有 package-info.java 的 GenericGenerator
【发布时间】：2021-05-10 22:40:33
【问题描述】：

我有一个名为Tasit 的实体，如下所示。

package tr.com.entity;

import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.Table;
import tr.com.MyGenerator;
    
@Entity
public class Tasit {
    
  @Id
  @GeneratedValue(generator = "ID_GENERATOR")
  private Long id;
    
  @Column(name = "TASIT_ADI")
  private String tasitAdi;
    
  public String getTasitAdi() {
     return tasitAdi;
  }
    
  public void setTasitAdi(String tasitAdi) {
    this.tasitAdi = tasitAdi;
  }
    
  public Tasit(Long tasitId, String tasitAdi) {
    super();
    this.id = tasitId;
    this.tasitAdi = tasitAdi;
  }
    
  public Tasit(String tasitAdi) {
    super();
    this.tasitAdi = tasitAdi;
  }
    
  public Long getId() {
    return id;
  }
    
  public Tasit() {
    super();
  }
}

正如您在Tasit 实体中看到的那样，有@GeneratedValue(generator = "ID_GENERATOR")。

我添加tr.com.entity 包package-info.java 类。我的目标是写一个Generator 并用于tr.com.entity 包中的所有实体

我的package-info.java 班级也在下面

@org.hibernate.annotations.GenericGenerator(
   name = "ID_GENERATOR",
   strategy =  "enhanced-sequence",
   parameters = {
      @org.hibernate.annotations.Parameter(
           name = "sequence_name",
           value = "JPWH_SEQUENCE"
      ),
      @org.hibernate.annotations.Parameter(
           name = "initial_value",
           value = "1000"
      )
    }
)
package tr.com.entity;

通过这样做，我尝试在TASIT 表中插入任何数据。但是当我运行适当的运行器代码以将数据插入到 TASIT 表中时，出现异常。

Exception in thread "main" java.lang.ExceptionInInitializerError
Caused by: org.hibernate.AnnotationException: Unknown Id.generator: ID_GENERATOR
    at org.hibernate.cfg.BinderHelper.makeIdGenerator(BinderHelper.java:639)
    at org.hibernate.cfg.AnnotationBinder.processId(AnnotationBinder.java:2287)
    at org.hibernate.cfg.AnnotationBinder.processElementAnnotations(AnnotationBinder.java:2193)
    at org.hibernate.cfg.AnnotationBinder.processIdPropertiesIfNotAlready(AnnotationBinder.java:895)
    at org.hibernate.cfg.AnnotationBinder.bindClass(AnnotationBinder.java:728)
    at org.hibernate.cfg.Configuration$MetadataSourceQueue.processAnnotatedClassesQueue(Configuration.java:3625)
    at org.hibernate.cfg.Configuration$MetadataSourceQueue.processMetadata(Configuration.java:3579)
    at org.hibernate.cfg.Configuration.secondPassCompile(Configuration.java:1381)
    at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1786)
    at tr.com.hibernate.test.TasitTest.<clinit>(TasitTest.java:47)

任何帮助将不胜感激。

【问题讨论】：

你使用什么休眠版本？请同时显示您的休眠配置。
休眠版本为4.0.2

标签： java hibernate jpa annotations

【解决方案1】：

Hibernate 配置如下

<?xml version="1.0" encoding="UTF-8"?>

<!DOCTYPE hibernate-configuration PUBLIC
  "-//Hibernate/Hibernate Configuration DTD//EN"
  "http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">

<hibernate-configuration>
    <session-factory>
        <property name="hibernate.id.new_generator_mappings" >true</property>
        <property name="connection.driver_class">oracle.jdbc.OracleDriver</property>
        <property name="connection.url">jdbc:oracle:thin:@HP-BILGISAYAR:1521:ORCL</property>
        <property name="connection.username">hr</property>
        <property name="connection.password">hr</property>


        <property name="connection.pool_size">1</property>

         <property name="dialect">org.hibernate.dialect.Oracle8iDialect</property>

         <property name="cache.provider_class">org.hibernate.cache.NoCacheProvider</property> 
         <property name="cache.use_second_level_cache">true</property>   
         <property name="cache.region.factory_class">org.hibernate.cache.ehcache.EhCacheRegionFactory</property> 
        
        <property name="show_sql">true</property>

        <property name="hbm2ddl.auto">update</property>  


<mapping class="tr.com.entity.Tasit"/> 

    </session-factory>
</hibernate-configuration>

【讨论】：