Java API或代码：Hibernate3和4之间的区别？

我粘贴了Hibernate 3配置文件、SessionFactory类来配置这个config.xml和一个带有JPA注释的bean。我想知道如果我使用的是Hibernate4，那么在代码级别的上下文中会有什么变化，或者在外行语言中会有什么非常广泛的差异或进步

hibernate.cfg.xml

豆类

hibernate.cfg.xml 文件hibernate.cfg.xml很好。hibernate-configuration-3.0.dtd中的版本仍然是3.0，这看起来可能令人困惑，但事实就是如此。DTD未更新。也许您想使用以hibernate为前缀的名称，例如

hibernate.show_sql

而不是

show_sql

。属性的名称可以从中找到。通常使用的DTD\U位置是

http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd

（vs…sourceforge…），但两者都应该有效

建筑会话工厂 正如您从中看到的，buildSessionFactory已被弃用。这就是它在4.x中的构建方式：

Configuration conf = new Configuration();
conf.configure();
serviceRegistry = new ServiceRegistryBuilder().applySettings(conf.getProperties()).buildServiceRegistry();        
sessionFactory = configuration.buildSessionFactory(serviceRegistry);

在文档中的许多地方，这仍然不是最新的

注释实体

---

一般来说，不需要更改bean类中的映射。原因是您使用的是正常的JPA映射，Hibernate 3也是JPA规范中描述的实现。

请不要投反对票。这是一个重要的问题，我将要求在我的项目中进行技术更改。不评论背后的原因就投反对票是没有建设性的

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

public class SessionFactoryHelper {
    private static final SessionFactory sessionFactory;

    static {
        try {            
            /*
             * Build a SessionFactory object from session-factory configuration 
             * defined in the hibernate.cfg.xml file. In this file we register 
             * the JDBC connection information, connection pool, the hibernate 
             * dialect that we used and the mapping to our hbm.xml file for each 
             * POJO (Plain Old Java Object).
             * 
             */
            sessionFactory = new Configuration().configure().buildSessionFactory();
        } catch (Throwable e) {
            System.err.println("Error in creating SessionFactory object." 
                + e.getMessage());
            throw new ExceptionInInitializerError(e);
        }
    }

    /*
     * A static method for other application to get SessionFactory object 
     * initialized in this helper class.
     * 
     */
    public static SessionFactory getSessionFactory() {
        return sessionFactory;
    }
}

import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.Table;

@Entity
@Table(name="USER1")
public class User1 {

    private Long id;
    private String name;
    private String gender;
    private String country;
    private String aboutYou;
    private Boolean mailingList;

    @Id
    @GeneratedValue
    @Column(name="USER_ID") 
    public Long getId() {
        return id;
    }
    public void setId(Long id) {
        this.id = id;
    }

    @Column(name="USER_NAME")
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }

    @Column(name="USER_GENDER")
    public String getGender() {
        return gender;
    }
    public void setGender(String gender) {
        this.gender = gender;
    }

    @Column(name="USER_COUNTRY")
    public String getCountry() {
        return country;
    }
    public void setCountry(String country) {
        this.country = country;
    }

    @Column(name="USER_ABOUT_YOU")
    public String getAboutYou() {
        return aboutYou;
    }
    public void setAboutYou(String aboutYou) {
        this.aboutYou = aboutYou;
    }

    @Column(name="USER_MAILING_LIST")
    public Boolean getMailingList() {
        return mailingList;
    }
    public void setMailingList(Boolean mailingList) {
        this.mailingList = mailingList;
    }

}

Configuration conf = new Configuration();
conf.configure();
serviceRegistry = new ServiceRegistryBuilder().applySettings(conf.getProperties()).buildServiceRegistry();        
sessionFactory = configuration.buildSessionFactory(serviceRegistry);