org.hibernate.SessionException: Session was already closed at org.hibernate.in問題

錯誤的信息：

org.hibernate.SessionException: Session was already closed
at org.hibernate.internal.SessionImpl.close(SessionImpl.java:411)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.hibernate.context.internal.ThreadLocalSessionContext$TransactionProtectionWrapper.invoke(ThreadLocalSessionContext.java:356) at com.sun.proxy.$Proxy25.close(Unknown Source)
at test.TestQuery.testAll(TestQuery.java:30)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:44)
at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:15)
at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:41)
at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:20)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:76)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:50)
at org.junit.runners.ParentRunner$3.run(ParentRunner.java:193)
at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:52)
at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:191)
at org.junit.runners.ParentRunner.access$000(ParentRunner.java:42)
at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:184)
at org.junit.runners.ParentRunner.run(ParentRunner.java:236)
at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:86)
at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:538)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:760)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:460)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:206)

• 異常
  注：其實這個異常並不影響正常的結果，結果還是能夠出來滴，只不過看的有點礙眼。。。

迴歸正題，先看整個工程結構

1.主要是在hibernate.cfg.xml里加入了這樣的一個配置

<!-- session對象的生命週期與本地線程綁定 -->
<property name="hibernate.current_session_context_class">thread</property>

2.然後在HibernateUtils工具類裏配置了
return sessionFactory.getCurrentSession();// 從線程中獲取session

package util;

import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.cfg.Configuration;

public class HibernateUtils {
    private final static Configuration cfg;
    private final static SessionFactory sessionFactory;
    static {
        cfg = new Configuration().configure();
        sessionFactory = cfg.buildSessionFactory();
    }

    private HibernateUtils() {
    }

    public static Session getSession() {
        return sessionFactory.getCurrentSession();// 從線程中獲取session
    }

    public static SessionFactory getSessionFactory() {
        return sessionFactory;
    }
}

3.之後在調用的過程中，做一個查詢全部的測試

package test;
import java.util.List;
import org.hibernate.Query;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import org.junit.Test;

import bean.User;
import util.HibernateUtils;

/**
 * Query查詢測試<br/>
 * create by LINKSINKE on 2020/3/25
 */
public class TestQuery {
    @Test
    public void testAll() {
        SessionFactory sessionFactory = HibernateUtils.getSessionFactory();
        Session session = HibernateUtils.getSession();
        Transaction tx = session.beginTransaction();
        Query query = session.createQuery("from User");
        List<User> lis = query.list();
        for (User user : lis) {
            System.out.println(user);
        }
        tx.commit();
        session.close();
        sessionFactory.close();
    }
}

運行後的效果是能夠查詢出來，再回過頭看看錯誤的信息，會發現session was already closed，這句意思就是session已經被關閉了

難道是我的那個測試里加入了session.close()??? 從而導致了這個錯誤？？？
去註釋看看，再次運行後錯誤沒有了。。。看來這個不需要再次手動關閉，線程那邊幫我們處理了

翻了一下hibernate的參考文檔