java - 查找时的 Eclipselink NPE

Question

当向实体发出简单的“查找”操作时，Eclipselink 会抛出 NPE:

java.lang.NullPointerException: null
    at org.eclipse.persistence.internal.jpa.CMP3Policy.createPrimaryKeyFromId(CMP3Policy.java:224)
    at org.eclipse.persistence.internal.jpa.EntityManagerImpl.findInternal(EntityManagerImpl.java:808)
    at org.eclipse.persistence.internal.jpa.EntityManagerImpl.find(EntityManagerImpl.java:730)
    at org.eclipse.persistence.internal.jpa.EntityManagerImpl.find(EntityManagerImpl.java:599)

该实体使用 Multi-Tenancy 和每租户一张表策略。

Answer 1

确保您在实体管理器上设置租户属性，如下所示:

String tenant = // ...
EntityManager em = // ...
em.setProperty(PersistenceUnitProperties.MULTITENANT_PROPERTY_DEFAULT, tenant);