java - Hibernate无法创建表

Question

我正在编写一个简单的代码来测试hibernate，其中包含主类，模型类和hibernate配置文件。但是我的日志在打印行后卡住了

**Hibernate: drop table if exists USER_DETAIL**

模型类:

    package com.test.hibernate.koushik;


import java.util.Date;

import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.Lob;
import javax.persistence.Table;
import javax.persistence.Temporal;
import javax.persistence.TemporalType;
import javax.persistence.Transient;


@Entity
@Table(name="USER_DETAIL")
public class UserDetails {

    @Id
    @GeneratedValue 
    @Column(name="USER_ID")
    private int userId;

    @Column(name="USER_NAME")
    private String userName;

    public int getUserId() {
        return userId;
    }

    public void setUserId(int userId) {
        this.userId = userId;
    }

    public String getUserName() {
        return userName + " From getter";
    }

    public void setUserName(String userName) {
        this.userName = userName;
    }


}

主类:

package com.test.hibernate.koushik;

import java.util.Date;

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

public class Main {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        UserDetails userdetail = new UserDetails();
        userdetail.setUserName("Hemkar");

        SessionFactory sessionFactory= new AnnotationConfiguration().configure().buildSessionFactory();
        Session session= sessionFactory.openSession();
        session.beginTransaction();
        session.save(userdetail);
        session.getTransaction().commit();
        session.close();
        sessionFactory.close();

    }

}

配置xml文件

<?xml version='1.0' encoding='utf-8'?>
<!DOCTYPE hibernate-configuration PUBLIC
        "-//Hibernate/Hibernate Configuration DTD 3.0//EN"
        "http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">

<hibernate-configuration>
    <session-factory>
        <!-- Database connection settings -->
        <property name="connection.driver_class">com.mysql.jdbc.Driver</property>
        <property name="connection.url">jdbc:mysql://localhost:3306/test_db</property>
        <property name="connection.username">root</property>
        <property name="connection.password">root</property>

        <!-- JDBC connection pool (use the built-in) -->
        <property name="connection.pool_size">1</property>

        <!-- SQL dialect -->
        <property name="dialect">org.hibernate.dialect.MySQLDialect</property>

        <!-- Disable the second-level cache  -->
        <property name="cache.provider_class">org.hibernate.cache.NoCacheProvider</property>

        <!-- Echo all executed SQL to stdout -->
        <property name="show_sql">true</property>

      <!-- Drop the existing tables and create new one -->
  <property name="hbm2ddl.auto">create</property>

        <!-- Mention here all the model classes along with their package name -->
        <mapping class="com.test.hibernate.koushik.UserDetails"/>


    </session-factory>
</hibernate-configuration>

日志:

Mar 19, 2015 12:32:27 PM org.hibernate.annotations.common.reflection.java.JavaReflectionManager <clinit>
INFO: HCANN000001: Hibernate Commons Annotations {4.0.5.Final}
Mar 19, 2015 12:32:27 PM org.hibernate.Version logVersion
INFO: HHH000412: Hibernate Core {4.3.8.Final}
Mar 19, 2015 12:32:27 PM org.hibernate.cfg.Environment <clinit>
INFO: HHH000206: hibernate.properties not found
Mar 19, 2015 12:32:27 PM org.hibernate.cfg.Environment buildBytecodeProvider
INFO: HHH000021: Bytecode provider name : javassist
Mar 19, 2015 12:32:27 PM org.hibernate.cfg.Configuration configure
INFO: HHH000043: Configuring from resource: /hibernate.cfg.xml
Mar 19, 2015 12:32:27 PM org.hibernate.cfg.Configuration getConfigurationInputStream
INFO: HHH000040: Configuration resource: /hibernate.cfg.xml
Mar 19, 2015 12:32:27 PM org.hibernate.internal.util.xml.DTDEntityResolver resolveEntity
WARN: HHH000223: Recognized obsolete hibernate namespace http://hibernate.sourceforge.net/. Use namespace http://www.hibernate.org/dtd/ instead. Refer to Hibernate 3.6 Migration Guide!
Mar 19, 2015 12:32:27 PM org.hibernate.cfg.Configuration doConfigure
INFO: HHH000041: Configured SessionFactory: null
Mar 19, 2015 12:32:28 PM org.hibernate.engine.jdbc.connections.internal.DriverManagerConnectionProviderImpl configure
WARN: HHH000402: Using Hibernate built-in connection pool (not for production use!)
Mar 19, 2015 12:32:28 PM org.hibernate.engine.jdbc.connections.internal.DriverManagerConnectionProviderImpl buildCreator
INFO: HHH000401: using driver [com.mysql.jdbc.Driver] at URL [jdbc:mysql://localhost:3306/test_db]
Mar 19, 2015 12:32:28 PM org.hibernate.engine.jdbc.connections.internal.DriverManagerConnectionProviderImpl buildCreator
INFO: HHH000046: Connection properties: {user=root, password=****}
Mar 19, 2015 12:32:28 PM org.hibernate.engine.jdbc.connections.internal.DriverManagerConnectionProviderImpl buildCreator
INFO: HHH000006: Autocommit mode: false
Mar 19, 2015 12:32:28 PM org.hibernate.engine.jdbc.connections.internal.DriverManagerConnectionProviderImpl configure
INFO: HHH000115: Hibernate connection pool size: 1 (min=1)
Mar 19, 2015 12:32:28 PM org.hibernate.dialect.Dialect <init>
INFO: HHH000400: Using dialect: org.hibernate.dialect.MySQLDialect
Mar 19, 2015 12:32:28 PM org.hibernate.engine.jdbc.internal.LobCreatorBuilder useContextualLobCreation
INFO: HHH000423: Disabling contextual LOB creation as JDBC driver reported JDBC version [3] less than 4
Mar 19, 2015 12:32:29 PM org.hibernate.engine.transaction.internal.TransactionFactoryInitiator initiateService
INFO: HHH000399: Using default transaction strategy (direct JDBC transactions)
Mar 19, 2015 12:32:29 PM org.hibernate.hql.internal.ast.ASTQueryTranslatorFactory <init>
INFO: HHH000397: Using ASTQueryTranslatorFactory
Mar 19, 2015 12:32:30 PM org.hibernate.tool.hbm2ddl.SchemaExport execute
INFO: HHH000227: Running hbm2ddl schema export
Hibernate: drop table if exists USER_DETAIL

此应用程序无法创建表的原因是什么。

Answer 1

首先检查您的数据库中是否已经有此表，如果有，请尝试删除手动并再次运行您的代码，如果不起作用，请尝试这样做。

persistence.xml

<?xml version="1.0" encoding="UTF-8"?>
<persistence version="2.1" 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">
    <persistence-unit name="Test">

    <class>test.UserDetail</class>
    <properties>
        <property name="hibernate.connection.username" value="admin"/>
        <property name="hibernate.connection.password" value="admin"/>
        <property name="hibernate.connection.url" value="jdbc:oracle:thin:@//..."/>
        <property name="hibernate.connection.driver_class" value="oracle.jdbc.driver.OracleDriver"/>
        <property name="hibernate.cache.provider_class" value="org.hibernate.cache.NoCacheProvider"/>
        <property name="hibernate.dialect" value="org.hibernate.dialect.Oracle9Dialect"/>
        <property name="hibernate.connection.autocommit" value="false"/>
        <property name="hibernate.hbm2ddl.auto" value="create"/>
    </properties>
</persistence-unit>

EntityManagerUtil.java 封装测试；

import javax.persistence.EntityManager;
import javax.persistence.EntityManagerFactory;
import javax.persistence.Persistence;

public class EntityManagerUtil {

private static EntityManagerFactory factory = null;
private static EntityManager em = null;

public static EntityManager getEntityManager(){
    if (factory == null) {
        factory = Persistence.createEntityManagerFactory("Test");
    }

    if (em == null){
        em = factory.createEntityManager();
    }

    return em;
}

}

Main.java

package test;

import javax.persistence.EntityManager;

public class Main {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        UserDetail userdetail = new UserDetail();
        userdetail.setUserName("zzzz");

        EntityManager em = EntityManagerUtil.getEntityManager();

        em.getTransaction().begin();
        em.persist(userdetail);
        em.getTransaction().commit();
        em.close();
        System.out.println("insert with success");

    }

}