Hibernate工具类丰富和Hql用法 对象属性名与关键字冲突

HibernateUtil:

package hibernate.util;import java.io.Serializable;import org.hibernate.HibernateException;import org.hibernate.Session;import org.hibernate.SessionFactory;import org.hibernate.cfg.AnnotationConfiguration;import com.zxf.model.Student;public class HibernateUtil {    private static final SessionFactory sessionFactory = buildSessionFactory();    public static SessionFactory buildSessionFactory() {    if(sessionFactory != null) {    return sessionFactory;    } else {            try {                return new AnnotationConfiguration().configure().buildSessionFactory();            }            catch (Throwable ex) {                System.err.println("Initial SessionFactory creation failed." + ex);                throw new ExceptionInInitializerError(ex);            }    }    }    public static SessionFactory getSessionFactory() {        return sessionFactory;    }        public static void add(Object o) {    Session session = null;    try {    session = sessionFactory.openSession();    session.beginTransaction();    session.save(o);    session.getTransaction().commit();    } catch (HibernateException e) {    e.printStackTrace();    } finally {    session.close();    }    }        public static void update(Object o) {    Session session = null;    try {    session = sessionFactory.openSession();    session.beginTransaction();    session.update(o);    session.getTransaction().commit();    } catch (HibernateException e) {    e.printStackTrace();    } finally {    session.close();    }    }        public static void delete(Object o) {    Session session = null;    try {    session = sessionFactory.openSession();    session.beginTransaction();    session.delete(o);    session.getTransaction().commit();    } catch (HibernateException e) {    e.printStackTrace();    } finally {    session.close();    }    }        public static Object get(Class className,Serializable id) {    Session session = null;    Object o = null;    try {    session = sessionFactory.openSession();    o = session.get(className, id);    } catch (HibernateException e) {    e.printStackTrace();    return null;    } finally {    if(session != null) {        session.close();    }    }    return o;    }}

HQL:

import hibernate.util.HibernateUtil;import java.util.List;import org.hibernate.Query;import org.hibernate.Session;import org.junit.Test;import com.zxf.model.Student;public class HQLTest {@Testpublic void query01() {Query query = null;Session session = null;List<Student> students = null;String hql = "from Student as user where user.name=?";session = HibernateUtil.buildSessionFactory().openSession();query = session.createQuery(hql);query.setString(0, "teeny");students = query.list();//query.uniqueResult();唯一记录for(Student s:students) {System.out.println(s.getName() + "----" + s.getAge());}}}

Critera:

//Critera查询@Testpublic void query04() {Criteria cri = null;Session session = null;List<Student> students = null;try {session = HibernateUtil.buildSessionFactory().openSession();cri = session.createCriteria(Student.class);cri.add(Restrictions.eq("name", "jason"));//添加对于Student对象的约束条件cri.add(Restrictions.eq("age",20));students = cri.list();//cri.uniqueResult();唯一记录for(Student s:students) {System.out.println(s.getName() + "----" + s.getAge());}} catch (HibernateException e) {e.printStackTrace();} finally {if(session != null) {session.close();}}}

对象名与关键字冲突：

<hibernate-mapping package="com.zxf.model">    <class name="Student" table="Student">        <id name="id"></id>        <property name="name"/>        <property name="age"/>    </class></hibernate-mapping>

table名冲突，比如User在sqlserver和oracle里面都是关键字，可以指定配置中table属性重新指定一个table，或者是用``将表名括起来，这样数据库就不会把它当关键字对待，而是看做普通字符串，如下：

<hibernate-mapping package="com.zxf.model">    <class name="Student" table="`Student`">        <id name="id"></id>        <property name="name" column="`name`"/>        <property name="age"/>    </class></hibernate-mapping>