为什么我的EclipseLink查询结果缓存不工作 [英] Why is my EclipseLink Query Results Cache NOT working

问题描述

我正在开发一个TomEE网站，我想使用EclipseLink查询结果缓存（L2）工作，但每次重新加载我的网页时，SELECT查询正在运行（通过mysql的general_log检查）。

我的数据库实体如下所示：

  @Entity（name =item ）
 @NamedQueries（{
 @NamedQuery（name =ItemEntity.getAllList，
 query =从mypackage.entity.ItemEntity itemEntity中选择不同的itemEntity，
 hints = {
 @QueryHint（name =eclipselink.query-results-cache，value =true），
 @QueryHint（name =eclipselink.query-results-cache.size，value = 1000），
 @QueryHint（name =eclipselink.query-results-cache.expiry，value =10000），// 10秒测试但不工作
 @QueryHint（name =eclipselink.query-results-cache.type，value =FULL）
} 
）
}）
 @org .eclipse.persistence.annotations.Cache（
 type = CacheType.FULL，
 size = 10000，
 expiry = 60000，//测试1分钟
 coordinationType = CacheCoordinationType.INVALIDATE_CHANGED_OBJECTS 
）
 public class ItemEntity implements Serializable，Comparable {
 
 @Id 
 @GeneratedValue（strategy = GenerationType.IDENTITY）
 private Integer id; 
 
 @Column（name =name，unique = true，nullable = false）
 private String name; 
 
 / *字段的getter和setter * / 
 
 public CompanyEntity（）{} 
 
 @Override 
 public int compareTo（Object o）{.......} 
} 
  

我的持久性.xml 如下所示：

 <？xml version =1.0encoding =UTF-8 ？> 
< persistence version =1.0
 xmlns =http://java.sun.com/xml/ns/persistence
 xmlns：xsi =http：// www。 w3.org/2001/XMLSchema-instance
 xsi：schemaLocation =http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/ persistence_1_0.xsd> 
< persistence-unit name =myprojectname-persistence-unittransaction-type =JTA> 
< jta-data-source> myprojectname-mysql-jdbc-jta-resource< / jta-data-source> 
< provider> org.eclipse.persistence.jpa.PersistenceProvider< / provider> 
<属性> 
< property name =eclipselink.target-databasevalue =org.eclipse.persistence.platform.database.MySQLPlatform/> 
< property name =eclipselink.cache.shared.defaultvalue =true/> 
< / properties> 
< / persistence-unit> 
< / persistence> 
  

我读取数据库表如下：

  @Stateful 
 public class CompanyDao {
 
 @PersistenceContext（unitName =myprojectname-persistence-unit，type = PersistenceContextType.EXTENDED）
保护EntityManager em; 
 
 public List< CompanyEntity> getAllList（）{
 return this.em.createNamedQuery（ItemEntity.getAllList，ItemEntity.class）.getResultList（）; 
} 
} 
  

依赖版本详细信息：

TomEE 1.7.2，Java EE6，openJPA 2.4.0，openEJB Java EE API 6.0-6，openEJB内核4.7.2，EclipseLink 2.6.2，MySQL 5.6.23，MySQL连接器/ J 5.1 .38（Tomcat连接池）

我看过一个类似的问题：
无法获得Eclipselink第2级缓存的工作
但是它没有描述OP如何缓存查询结果。

BTW，默认缓存（L2），带有 em.find（ItemEntity.class，id）; 正在工作很好。

我缺少什么？请帮助我。

解决方案

已解决。

EclipseLink 2.6.2，我降级到版本2.4.2，现在查询结果缓存工作如预期！

我猜EclipseLink 2.6.x或2.5.x不是与JPA 2.0.x兼容。
令人困惑的是，因为当我使用2.5.x或更高版本时，似乎仍然可以工作，BESIDES查询结果缓存的功能。

我的持久性。 xml现在看起来像现在，所以我可以得到日志输出：

 <？xml version =1.0encoding =UTF -8？> 
< persistence version =1.0
 xmlns =http://java.sun.com/xml/ns/persistence
 xmlns：xsi =http：// www。 w3.org/2001/XMLSchema-instance
 xsi：schemaLocation =http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/ persistence_1_0.xsd> 
< persistence-unit name =myprojectname-persistence-unittransaction-type =JTA> 
< jta-data-source> myprojectname-mysql-jdbc-jta-resource< / jta-data-source> 
< provider> org.eclipse.persistence.jpa.PersistenceProvider< / provider> 
<属性> 
< property name =eclipselink.target-databasevalue =org.eclipse.persistence.platform.database.MySQLPlatform/> 
< property name =eclipselink.logging.loggervalue =JavaLogger/> 
<！ - 注册MBean时出现问题：java.lang.NullPointerException的警告日志即使我设置了bellow 2属性也没有消失 - > 
<！ -  
< property name =eclipselink.register.dev.mbeanvalue =false/> 
< property name =eclipselink.register.run.mbeanvalue =false/> 
  - > 
 
< property name =eclipselink.cache.shared.defaultvalue =true/> 
< property name =eclipselink.logging.parametersvalue =true/> 
< property name =eclipselink.logging.timestampvalue =true/> 
< property name =eclipselink.logging.sessionvalue =true/> 
< property name =eclipselink.logging.threadvalue =true/> 
< property name =eclipselink.logging.exceptionsvalue =true/> 
< property name =eclipselink.logging.levelvalue =FINEST/> 
< / properties> 
< / persistence-unit> 
< / persistence> 
  

I am developing a website on TomEE, and I want to use the EclipseLink Query Results Cache (L2) working, but every time I reload my web page, SELECT query is running (checked via general_log of mysql).

My Database entity looks like below:

@Entity(name="item")
@NamedQueries({
        @NamedQuery(name="ItemEntity.getAllList",
                query="Select distinct itemEntity from mypackage.entity.ItemEntity itemEntity",
                hints={
                        @QueryHint(name="eclipselink.query-results-cache", value="true"),
                        @QueryHint(name="eclipselink.query-results-cache.size", value="1000"),
                        @QueryHint(name="eclipselink.query-results-cache.expiry", value="10000"), //10 secs for test but not working
                        @QueryHint(name="eclipselink.query-results-cache.type", value="FULL")
                }
        )
})
@org.eclipse.persistence.annotations.Cache(
        type= CacheType.FULL,
        size=10000,
        expiry=60000,  // 1 minute for test
        coordinationType= CacheCoordinationType.INVALIDATE_CHANGED_OBJECTS
)
public class ItemEntity implements Serializable, Comparable {

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Integer id;

    @Column(name="name", unique=true, nullable=false)
    private String name;

    /* getters and setters for fields */

    public CompanyEntity(){}

    @Override
    public int compareTo(Object o) {.......}
}

My persistence.xml looks like below:

<?xml version="1.0" encoding="UTF-8" ?>
<persistence version="1.0"
             xmlns="http://java.sun.com/xml/ns/persistence"
             xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
             xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_1_0.xsd">
    <persistence-unit name="myprojectname-persistence-unit" transaction-type="JTA">
        <jta-data-source>myprojectname-mysql-jdbc-jta-resource</jta-data-source>
        <provider>org.eclipse.persistence.jpa.PersistenceProvider</provider>
        <properties>
            <property name="eclipselink.target-database" value="org.eclipse.persistence.platform.database.MySQLPlatform"/>
            <property name="eclipselink.cache.shared.default" value="true"/>
        </properties>
    </persistence-unit>
</persistence>

I read database table like below:

@Stateful
public class CompanyDao {

    @PersistenceContext(unitName = "myprojectname-persistence-unit", type = PersistenceContextType.EXTENDED)
    protected EntityManager em;

    public List<CompanyEntity> getAllList(){
        return this.em.createNamedQuery("ItemEntity.getAllList", ItemEntity.class).getResultList();
    }
}

Dependency version details:

TomEE 1.7.2, Java EE6, openJPA 2.4.0, openEJB Java EE API 6.0-6, openEJB core 4.7.2, EclipseLink 2.6.2, MySQL 5.6.23, MySQL connector/J 5.1.38 (Tomcat connection pool)

I've looked at a similar question: Can't get Eclipselink level 2 cache to work but it doesn't describe how the OP managed to cache query results.

BTW, the default cache (L2), with em.find(ItemEntity.class, id); is working just fine.

What am I missing? Please help me out.

解决方案

Solved.

I was using EclipseLink 2.6.2, I downgraded to version 2.4.2, and now Query Results Cache WORKS as expected!

I guess EclipseLink 2.6.x or 2.5.x is not quite compatible with JPA 2.0.x. It's confusing, because when I use 2.5.x or higher, those still seem to be working, BESIDES the feature of Query Results Cache.

My persistence.xml looks like bellow now, so I can get log output:

<?xml version="1.0" encoding="UTF-8" ?>
<persistence version="1.0"
             xmlns="http://java.sun.com/xml/ns/persistence"
             xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
             xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_1_0.xsd">
    <persistence-unit name="myprojectname-persistence-unit" transaction-type="JTA">
        <jta-data-source>myprojectname-mysql-jdbc-jta-resource</jta-data-source>
        <provider>org.eclipse.persistence.jpa.PersistenceProvider</provider>
        <properties>
            <property name="eclipselink.target-database" value="org.eclipse.persistence.platform.database.MySQLPlatform"/>
            <property name="eclipselink.logging.logger" value="JavaLogger"/>
            <!-- The warning log of "Problem while registering MBean: java.lang.NullPointerException" did not go away even if I set bellow 2 propertes -->
            <!--
            <property name="eclipselink.register.dev.mbean" value="false" />
            <property name="eclipselink.register.run.mbean" value="false" />
            -->

            <property name="eclipselink.cache.shared.default" value="true"/>
            <property name="eclipselink.logging.parameters" value="true"/>
            <property name="eclipselink.logging.timestamp" value="true"/>
            <property name="eclipselink.logging.session" value="true"/>
            <property name="eclipselink.logging.thread" value="true"/>
            <property name="eclipselink.logging.exceptions" value="true"/>
            <property name="eclipselink.logging.level" value="FINEST"/>
        </properties>
    </persistence-unit>
</persistence>

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