使用 hibernate 查询表时出错

Question

我正在尝试查询 MySQL 中名为student的表。这是结构：

这是我用来查询的 java 代码：

package com.luv2code.hibernate.demo;

import java.util.*;

import org.hibernate.*;
import org.hibernate.cfg.*;

import com.luv2code.hibernate.demo.entity.Student;

public class QueryStudentDemo {

    public static void main(String[] args) throws Exception {
        SessionFactory factory = new Configuration()
                                .configure("hibernate.cfg.xml")
                                .addAnnotatedClass(Student.class)
                                .buildSessionFactory();
        
        Session session = factory.getCurrentSession();
        
        try {
            session.beginTransaction();
            
            List<Student> list = session.createQuery("from Student").getResultList();
            
            session.getTransaction().commit();
            System.out.println(list);
        } finally {
            factory.close();
        }
    }

}

这是错误消息：

May 25, 2022 6:40:05 AM org.hibernate.Version logVersion
INFO: HHH000412: Hibernate ORM core version 5.6.5.Final
May 25, 2022 6:40:06 AM org.hibernate.annotations.common.reflection.java.JavaReflectionManager <clinit>
INFO: HCANN000001: Hibernate Commons Annotations {5.1.2.Final}
May 25, 2022 6:40:06 AM org.hibernate.engine.jdbc.connections.internal.DriverManagerConnectionProviderImpl configure
WARN: HHH10001002: Using Hibernate built-in connection pool (not for production use!)
May 25, 2022 6:40:06 AM org.hibernate.engine.jdbc.connections.internal.DriverManagerConnectionProviderImpl buildCreator
INFO: HHH10001005: using driver [com.mysql.cj.jdbc.Driver] at URL [jdbc:mysql://localhost:3306/hb_student_tracker?useSSL=false&serverTimezone=UTC]
May 25, 2022 6:40:06 AM org.hibernate.engine.jdbc.connections.internal.DriverManagerConnectionProviderImpl buildCreator
INFO: HHH10001001: Connection properties: {password=****, user=hbstudent}
May 25, 2022 6:40:06 AM org.hibernate.engine.jdbc.connections.internal.DriverManagerConnectionProviderImpl buildCreator
INFO: HHH10001003: Autocommit mode: false
May 25, 2022 6:40:06 AM org.hibernate.engine.jdbc.connections.internal.DriverManagerConnectionProviderImpl$PooledConnections <init>
INFO: HHH000115: Hibernate connection pool size: 1 (min=1)
May 25, 2022 6:40:07 AM org.hibernate.dialect.Dialect <init>
INFO: HHH000400: Using dialect: org.hibernate.dialect.MySQLDialect
May 25, 2022 6:40:07 AM org.hibernate.engine.jdbc.connections.internal.DriverManagerConnectionProviderImpl$PoolState stop
INFO: HHH10001008: Cleaning up connection pool [jdbc:mysql://localhost:3306/hb_student_tracker?useSSL=false&serverTimezone=UTC]
May 25, 2022 6:40:07 AM org.hibernate.engine.jdbc.connections.internal.DriverManagerConnectionProviderImpl$PooledConnections close
ERROR: Connection leak detected: there are 1 unclosed connections upon shutting down pool jdbc:mysql://localhost:3306/hb_student_tracker?useSSL=false&serverTimezone=UTC
May 25, 2022 6:40:07 AM org.hibernate.engine.jdbc.connections.internal.DriverManagerConnectionProviderImpl validateConnectionsReturned
ERROR: Connection leak detected: there are 1 unclosed connections!
Exception in thread "main" java.lang.reflect.UndeclaredThrowableException
    at jdk.proxy2/jdk.proxy2.$Proxy46.createQuery(Unknown Source)
    at com.luv2code.hibernate.demo.QueryStudentDemo.main(QueryStudentDemo.java:23)
Caused by: java.lang.reflect.InvocationTargetException
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:77)
    at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.base/java.lang.reflect.Method.invoke(Method.java:568)
    at org.hibernate.context.internal.ThreadLocalSessionContext$TransactionProtectionWrapper.invoke(ThreadLocalSessionContext.java:351)
    ... 2 more
Caused by: java.lang.NoClassDefFoundError: antlr/RecognitionException
    at org.hibernate.hql.internal.ast.ASTQueryTranslatorFactory.createQueryTranslator(ASTQueryTranslatorFactory.java:44)
    at org.hibernate.engine.query.spi.HQLQueryPlan.<init>(HQLQueryPlan.java:112)
    at org.hibernate.engine.query.spi.HQLQueryPlan.<init>(HQLQueryPlan.java:73)
    at org.hibernate.engine.query.spi.QueryPlanCache.getHQLQueryPlan(QueryPlanCache.java:162)
    at org.hibernate.internal.AbstractSharedSessionContract.getQueryPlan(AbstractSharedSessionContract.java:636)
    at org.hibernate.internal.AbstractSharedSessionContract.createQuery(AbstractSharedSessionContract.java:748)
    at org.hibernate.internal.AbstractSharedSessionContract.createQuery(AbstractSharedSessionContract.java:114)
    ... 7 more
Caused by: java.lang.ClassNotFoundException: antlr.RecognitionException
    at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:641)
    at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:188)
    at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:520)
    ... 14 more

这是referenced libraries的图像：

插入表工作正常。 只有查询不是。

这里的错误是什么？

如果需要额外信息，请发表评论。

更新：

当我将antlr添加到我的 class 路径时它起作用了

Answer 1

根据异常堆栈跟踪，似乎缺少antlr/RecognitionException class 文件。 添加以下依赖项并尝试。 这应该可以解决您的问题。

<dependency>
 <groupId>org.antlr</groupId>
 <artifactId>antlr-complete</artifactId>
 <version>3.5.3</version>
</dependency>