Question

开始学习hibernate。通过教程做所有事情，但当我尝试做简单的选择时，没有任何反应。不明白问题所在。

日志：

мар 28, 2016 12:54:44 PM org.hibernate.Version logVersion
INFO: HHH000412: Hibernate Core {5.1.0.Final}
мар 28, 2016 12:54:44 PM org.hibernate.cfg.Environment <clinit>
INFO: HHH000206: hibernate.properties not found
мар 28, 2016 12:54:44 PM org.hibernate.cfg.Environment buildBytecodeProvider
INFO: HHH000021: Bytecode provider name : javassist
мар 28, 2016 12:54:45 PM org.hibernate.annotations.common.reflection.java.JavaReflectionManager <clinit>
INFO: HCANN000001: Hibernate Commons Annotations {5.0.1.Final}
мар 28, 2016 12:54:45 PM org.hibernate.engine.jdbc.connections.internal.DriverManagerConnectionProviderImpl configure
WARN: HHH10001002: Using Hibernate built-in connection pool (not for production use!)
мар 28, 2016 12:54:45 PM org.hibernate.engine.jdbc.connections.internal.DriverManagerConnectionProviderImpl buildCreator
INFO: HHH10001005: using driver [com.mysql.jdbc.Driver] at URL [jdbc:mysql://localhost:3306/taskboard]
мар 28, 2016 12:54:45 PM org.hibernate.engine.jdbc.connections.internal.DriverManagerConnectionProviderImpl buildCreator
INFO: HHH10001001: Connection properties: {user=root, password=****}
мар 28, 2016 12:54:45 PM org.hibernate.engine.jdbc.connections.internal.DriverManagerConnectionProviderImpl buildCreator
INFO: HHH10001003: Autocommit mode: false
мар 28, 2016 12:54:45 PM org.hibernate.engine.jdbc.connections.internal.PooledConnections <init>
INFO: HHH000115: Hibernate connection pool size: 20 (min=1)
мар 28, 2016 12:54:45 PM org.hibernate.dialect.Dialect <init>
INFO: HHH000400: Using dialect: org.hibernate.dialect.MySQLDialect
мар 28, 2016 12:54:45 PM org.hibernate.validator.internal.util.Version <clinit>
INFO: HV000001: Hibernate Validator 5.2.4.Final
мар 28, 2016 12:54:45 PM org.hibernate.engine.jdbc.connections.internal.DriverManagerConnectionProviderImpl stop
INFO: HHH10001008: Cleaning up connection pool [jdbc:mysql://localhost:3306/taskboard]

User.java

@Entity
@Table(name="Users")
public class User {

@Id
@Column(name="id_user")
private Long id;

@Column(name="first_name")
private String firstName;

@Column(name="last_name")
private String lastName;

@Column(name="login")
private String login;

@Column(name="password")
private String password;
}//get&set

Main.java

SessionFactory sessionFactory = HibernateUtil.getSessionFactory();
    Session session = sessionFactory.openSession();

    List<User> users = null;

    try {
    session.beginTransaction();

    Criteria criteria = session.createCriteria(User.class);
    users = criteria.list();

    session.getTransaction().commit();

    } catch (Exception e) {
        session.getTransaction().rollback();
        e.printStackTrace();
    } finally {
        session.close();
        sessionFactory.close();
    }

    for (User user: users) {
        System.out.println(user.toString());
    }

的hibernate.cfg.xml

<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE hibernate-configuration PUBLIC "-//Hibernate/Hibernate Configuration DTD 3.0//EN" "http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
<session-factory>
    <property name="connection.driver_class">com.mysql.jdbc.Driver</property>
    <property name="connection.url">jdbc:mysql://localhost:3306/taskboard</property>
    <property name="connection.username">root</property>
    <property name="connection.password">1234</property>
    <property name="dialect">org.hibernate.dialect.MySQLDialect</property>
    <property name="show_sql">true</property>
    <property name="hbm2ddl.auto">update</property>

    <mapping class="User" />
</session-factory>
</hibernate-configuration>

HibernateUtil.java

public class HibernateUtil {
private static SessionFactory sessionFactory = null;

static {
    Configuration cfg = new Configuration().configure();
    StandardServiceRegistryBuilder builder =  new StandardServiceRegistryBuilder()
            .applySettings(cfg.getProperties());

    sessionFactory = cfg.buildSessionFactory(builder.build());
}

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

Answer 1

对于Users table，数据库可能没有任何内容。首先插入一些数据。然后检查。

Answer 2

据我记忆，较新版本的hibernate不再支持hibernate配置文件中的public TextField l4M1ICT01; public TextField l4M1ICT02; public TextField l4M1CourseWork; public TextField l4M1Average; public int average_1; public int credit_1; public void l4M1AverageButtonClicked(ActionEvent event) throws IOException { int l4M1ICT01_1 = Integer.parseInt(l4M1ICT01.getText()); int l4M1ICT02_1 = Integer.parseInt(l4M1ICT02.getText()); int l4M1CourseWork_1 = Integer.parseInt(l4M1CourseWork.getText()); average_1 = (l4M1ICT01_1 + l4M1ICT02_1 + l4M1CourseWork_1) / 3; l4M1Average.setText(average_1 + ""); if(average_1 >= 40){ credit_1 = 20; }else{ credit_1 = 0; } System.out.println(credit_1); } public void l4M1NextButtonClicked(ActionEvent event) throws IOException { ((Node) (event.getSource())).getScene().getWindow().hide(); //loading the next scene Parent parent = FXMLLoader.load(getClass().getResource("L4M2.fxml")); Stage stage = new Stage(); Scene scene = new Scene(parent); stage.setScene(scene); stage.setTitle("Level 4 Module 2"); //making the scene appear on the screen stage.show(); } public TextField l4M2ICT01; public TextField l4M2ICT02; public TextField l4M2CourseWork; public TextField l4M2Average; public int average_2; public void l4M2AverageButtonClicked(ActionEvent event) throws IOException { int l4M2ICT01_1 = Integer.parseInt(l4M2ICT01.getText()); int l4M2ICT02_1 = Integer.parseInt(l4M2ICT02.getText()); int l4M2CourseWork_1 = Integer.parseInt(l4M2CourseWork.getText()); average_2 = (l4M2ICT01_1 + l4M2ICT02_1 + l4M2CourseWork_1) / 3; l4M2Average.setText(average_2 + ""); System.out.println(credit_1); } public void l4M2NextButtonClicked(ActionEvent event) throws IOException { ((Node) (event.getSource())).getScene().getWindow().hide(); //loading the next scene Parent parent = FXMLLoader.load(getClass().getResource("L4M3.fxml")); Stage stage = new Stage(); Scene scene = new Scene(parent); stage.setScene(scene); stage.setTitle("Level 4 Module 3"); //making the scene appear on the screen stage.show(); }。

你可以删除它，而不是尝试使用

您的<mapping class= .../>静态区块中的
cfg.addAnnotatedClass(User.class)。

另外，您可能需要考虑使用构建HibernateUtil的最新方法，因为sessionFactory方式已被弃用。有关详细信息，请参阅Native Bootstrapping部分。

Hibernate使用查询

2 个答案: