对于JTA事务类型，java JPA更改不会持久化

Question

我正在使用JTA和我的毅力。xml如下所示

<?xml version="1.0" encoding="UTF-8" ?>
<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" version="1.0"
             xmlns="http://java.sun.com/xml/ns/persistence">
  <persistence-unit name="test" transaction-type="JTA">
    <provider>org.eclipse.persistence.jpa.PersistenceProvider</provider>
    <jta-data-source>jdbc/testDS</jta-data-source>
    <class>test.entity.Employees</class>
    <exclude-unlisted-classes>true</exclude-unlisted-classes>
    <properties>
      <property name="eclipselink.target-server" value="OC4J"/>
      <property name="javax.persistence.target-database" value="Oracle"/>
      <property name="javax.persistence.logging.parameters" value="TRUE"/>
    </properties>
  </persistence-unit>
</persistence>

因为我使用的是JTA，所以我没有EntityTransaction

Java代码片段

    Employees emp = new Employees();
    emp.setEmpNumber(empPOJO.getEmpNumber());
    final EntityManager em = getEntityManager();
    try {           
            em.merge(vehicleInspection);            
    } finally {
        if (em != null && em.isOpen()) {
            em.close();
        }
    }
}

然而，我无法在数据库中保存更改。是因为没有承诺吗

Answer 1

启用事务后，您必须正确处理它们。 查看此wiky和JPA sample code以了解更多详细信息