Hibernate的配置的读取

hibernate从配置文件中读取和数据库连接有关的信息有两种格式,一种是XML文件配置,一种是属性文件配置即properties文件来配置,由于配置文件的不同导致使用hibernate api的时候会有微小差别,现在以hibernate2版本为例分别具体说明

1. 使用xml文件配置，文件格式一般为.cfg.xml,下面列举出了一个简要的配置

<!DOCTYPE hibernate-configuration PUBLIC
          "-//Hibernate/Hibernate Configuration DTD 2.0//EN"
          "http://hibernate.sourceforge.net/hibernate-configuration-2.0.dtd">


<hibernate-configuration>

    <session-factory>
        <property name="connection.username">root</property>
        <property name="connection.url">jdbc:mysql://localhost:3306/mydb</property>
        <property name="dialect">net.sf.hibernate.dialect.MySQLDialect</property>
        <property name="myeclipse.connection.profile">mydb</property>
        <property name="connection.password">root</property>
        <property name="connection.driver_class">org.gjt.mm.mysql.Driver</property>

   <mapping resource="com/beans/customer.hbm.xml"/>
    </session-factory>

</hibernate-configuration>

其中connection.username制定用户名,connection.url制定数据库连接的url,dialect制定数据库方言,connection.password制定制定用户的密码,connection.driver_class制定驱动类,<mapping resource="com/beans/customer.hbm.xml"/>制定其中一个orm映射文件的位置,

下面列举出customer.hbm.xml的一个样例

<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC
    "-//Hibernate/Hibernate Mapping DTD 2.0//EN"
    "http://hibernate.sourceforge.net/hibernate-mapping-2.0.dtd" >

<hibernate-mapping>
<class name = "com.beans.Customer" table="customers" >
   <id name = "id" column="id" type = "long">
    <generator class="increment"/>
   </id>
   <property name="name" column = "name" type = "string" not-null="true" />
   <property name="email" column = "email" type = "string" not-null="true" />
   <property name="password" column = "password" type = "string" not-null="true" />
   <property name="phone" column = "phone" type = "int" />
   <property name="address" column = "address" type = "string" />
   <property name="sex" column = "sex" type = "character" />
</class>
</hibernate-mapping>

同时需要建立数据库对应的java类文件

import java.io.Serializable;

public class Customer implements Serializable{
private Long id;
private String name;
private String email;
private String password;
private int phone;
private char sex;
private String address;
public Long getId() {
   return id;
}
public void setId(Long id) {
   this.id = id;
}
public String getName() {
   return name;
}
public void setName(String name) {
   this.name = name;
}
public String getEmail() {
   return email;
}
public void setEmail(String email) {
   this.email = email;
}
public String getPassword() {
   return password;
}
public void setPassword(String password) {
   this.password = password;
}
public int getPhone() {
   return phone;
}
public void setPhone(int phone) {
   this.phone = phone;
}
public char getSex() {
   return sex;
}
public void setSex(char sex) {
   this.sex = sex;
}
public String getAddress() {
   return address;
}
public void setAddress(String address) {
   this.address = address;
}
}

使用hibernate api时具体示例代码如下

public class BusinessService {
public static SessionFactory sessionFactory;
static{
   Configuration config = new Configuration();
   try {
//    config.addClass(Customer.class);
    sessionFactory = config.configure().buildSessionFactory();

      } catch (MappingException e) {
     // TODO Auto-generated catch block
     e.printStackTrace();
    }catch (HibernateException e) {
     // TODO Auto-generated catch block
     e.printStackTrace();
   }

}
public static void main(String[] args) {
   Class c = Customer.class;
   Customer customer = new Customer();
   customer.setName("aaa");
   customer.setPassword("1234");
   customer.setEmail("alei_1304@163.com");
   customer.setPhone(1234);
   customer.setAddress("北京市中关村");
   customer.setSex('M');
   try {
    Session session = sessionFactory.openSession();
    Transaction tx = session.beginTransaction();
    session.save(customer);
    tx.commit();
    session.close();
   } catch (HibernateException e) {
    // TODO Auto-generated catch block
    e.printStackTrace();
   }

}
}

其中采用xml文件配置,在初始化SessionFactory实例的时候需要采用new Configuration().configure().buildSessionFactory(),如果直接使用new Configuration().buildSessionFactory()会报异常java.lang.UnsupportedOperationException: The user must supply a JDBC connection

由于必须在xml配置文件中制定<mapping resource="com/beans/customer.hbm.xml"/>,所以在程序中无需再使用config.addClass(Customer.class),否则会导致异常net.sf.hibernate.MappingException: Error reading resource: com/beans/customer.hbm.xml
at net.sf.hibernate.cfg.Configuration.addResource(Configuration.java:340)
at net.sf.hibernate.cfg.Configuration.doConfigure(Configuration.java:1027)
at net.sf.hibernate.cfg.Configuration.doConfigure(Configuration.java:983)
at net.sf.hibernate.cfg.Configuration.configure(Configuration.java:911)
at net.sf.hibernate.cfg.Configuration.configure(Configuration.java:897)
at com.business.BusinessSe

补充：综合编程 , 其他综合 ,