我该如何避免它?
这是我的代码:
持久性.xml
<?xml version="1.0" encoding="UTF-8"?>
<persistence xmlns="http://xmlns.jcp.org/xml/ns/persistence"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/persistence
http://xmlns.jcp.org/xml/ns/persistence/persistence_2_1.xsd"
version="2.1">
<persistence-unit name="testdb" transaction-type="RESOURCE_LOCAL">
<provider>org.hibernate.jpa.HibernatePersistenceProvider</provider>
<properties>
<property name="hibernate.connection.driver_class" value="org.h2.Driver"/>
<property name="hibernate.connection.url" value="jdbc:h2:tcp://localhost:9092/~/h2dbs/testdb"/>
<property name="hibernate.connection.username" value="sa"/>
<property name="hibernate.connection.password" value=""/>
<property name="hibernate.connection.useUnicode" value="true"/>
<property name="hibernate.connection.characterEncoding" value="utf-8"/>
<property name="hibernate.show_sql" value="false"/>
</properties>
</persistence-unit>
</persistence>
PersistenceUtil.java
public class PersistenceUtil {
private static EntityManagerFactory entityManagerFactory;
static {
entityManagerFactory = Persistence.createEntityManagerFactory("testdb");
}
public static EntityManager getEntityManager() {
final EntityManager entityManager = entityManagerFactory.createEntityManager();
return entityManager;
}
}
和TestClass.java
public class TestClass {
public static void main(String[] args) {
final EntityManager em = PersistenceUtil.getEntityManager();
final EntityTransaction transaction = em.getTransaction();
transaction.begin();
final TestTable testTable = new TestTable();
testTable.setData("Sample Data");
em.merge(testTable);
transaction.commit();
em.close();
}
}
因此,当我在 TestClass 中运行 main 方法时,我会看到数据库中插入了一行,其中包含“示例数据”,但程序永远不会退出,它只会挂起..
我认为 Hibernate 正在创建一个线程,但如何避免它?
最佳答案
也尝试关闭entityManagerFactory,在你的PersistenceUtil中只需创建额外的方法来关闭entityManagerFactory
public class PersistenceUtil {
private static EntityManagerFactory entityManagerFactory;
static {
entityManagerFactory = Persistence.createEntityManagerFactory("testdb");
}
public static EntityManager getEntityManager() {
final EntityManager entityManager = entityManagerFactory.createEntityManager();
return entityManager;
}
public static void closeEntityManagerFactory() {
entityManagerFactory.close();
}
}
public class TestClass {
public static void main(String[] args) {
final EntityManager em = PersistenceUtil.getEntityManager();
final EntityTransaction transaction = em.getTransaction();
transaction.begin();
final TestTable testTable = new TestTable();
testTable.setData("Sample Data");
em.merge(testTable);
transaction.commit();
em.close():
PersistenceUtil.closeEntityManagerFactory()
}
}
关于java - 为什么 Hibernate 会阻止 Java 进程退出?,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/39248360/