我知道这已经被问过十二遍了。今天,我一定很沮丧,因为我尝试了一百种方法来修改xml文件,但我无法弄清楚。
运行驱动程序时出现错误堆栈:
16 [main] INFO org.hibernate.cfg.Environment - Hibernate 3.3.2.GA 31 [main] INFO org.hibernate.cfg.Environment - hibernate.properties not found 31 [main] INFO org.hibernate.cfg.Environment - Bytecode provider name : javassist 31 [main] INFO org.hibernate.cfg.Environment - using JDK 1.4 java.sql.Timestamp handling 78 [main] INFO org.hibernate.cfg.Configuration - configuring from resource: test_hibernate/hibernate.cfg.xml 78 [main] INFO org.hibernate.cfg.Configuration - Configuration resource: test_hibernate/hibernate.cfg.xml 125 [main] INFO org.hibernate.cfg.Configuration - Reading mappings from resource : test_hibernate/contact.hbm.xml Exception in thread "main" Could not parse mapping document from resource test_hibernate/contact.hbm.xml java.lang.NullPointerException at test_hibernate.MyExample.main(MyExample.java:29)
这是我如何建立表格的MySQL代码:
create database HibernateTest; drop table contact; Create table CONTACT( ID int(15), FIRSTNAME varchar(50) , LASTNAME varchar(50), EMAIL varchar(150)); describe contact;
这是我的映射文件:
<?xml version="1.0"?> <!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN" "http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd"> <hibernate-mapping> <class name="test_hibernate.Contact" table="CONTACT"> <id name="id" column="ID" > <generator class="increment" /> </id> <property name="firstName" column="FIRSTNAME" /> <property name="lastName" column="LASTNAME" /> <property name="email" column="EMAIL" /> </class> </hibernate-mapping>
这是我的配置文件:
<?xml version='1.0' encoding='utf-8'?> <!DOCTYPE hibernate-configuration PUBLIC "-//Hibernate/Hibernate Configuration DTD//EN" "http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd"> <hibernate-configuration> <session-factory> <property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property> <property name="hibernate.connection.url">jdbc:mysql://localhost/hibernatetest</property> <property name="hibernate.connection.username">###</property> <property name="hibernate.connection.password">###</property> <property name="hibernate.connection.pool_size">10</property> <property name="show_sql">true</property> <property name="dialect">org.hibernate.dialect.MySQLDialect</property> <property name="hibernate.hbm2ddl.auto">update</property> <!-- Mapping files --> <mapping resource="test_hibernate/contact.hbm.xml"/> </session-factory> </hibernate-configuration>
任何帮助表示赞赏,谢谢!
一些其他信息:安装程序包test_hibernate和这是我的持久性文件:
package test_hibernate; public class Contact { private String firstName; private String lastName; private String email; private long id; public String getEmail() { return email; } public String getFirstName() { return firstName; } public String getLastName() { return lastName; } public void setEmail(String string) { email = string; } public void setFirstName(String string) { firstName = string; } public void setLastName(String string) { lastName = string; } public long getId() { return id; } public void setId(long l) { id = l; } }
这是我的司机:
package test_hibernate; import org.hibernate.Session; import org.hibernate.SessionFactory; import org.hibernate.cfg.Configuration; import org.hibernate.Transaction; public class MyExample { public static void main(String[] args) { Session session = null; try{ // This step will read hibernate.cfg.xml and prepare hibernate for use SessionFactory sessionFactory = new Configuration().configure("hibernate.cfg.xml").buildSessionFactory(); session=sessionFactory.openSession(); Transaction tx = session.beginTransaction(); //Create new instance of Contact and set values in it by reading them from form object System.out.println("Inserting Record"); Contact contact = new Contact(); contact.setId(3); contact.setFirstName("Smitha"); contact.setLastName("Rao"); contact.setEmail("smithaxxx@yahoo.com"); session.save(contact); tx.commit(); System.out.println("Done"); }catch(Exception e){ System.out.println(e.getMessage()); }finally{ // Actual contact insertion will happen at this step session.flush(); session.close(); } } }
您的映射文件看起来不错。我认为这可能是由于您在双引号中使用了 “ 或 ” 而不是 “ 。”请尝试在所有双引号中使用 “ 。