Hibernate 5.2版本以前的Criteria查询

Hibernate 5.2版本以前的Criteria查询

Query By Criteria特点：使用面向对象的方式查询package com.qfedu.hibernate.test;import java.util.List;import org.hibernate.Criteria;import org.hibernate.Session;import org.hibernate.Transaction;import org.hibernate.criterion.ProjectionList;import org.hibernate.criterion.Projections;import org.hibernate.criterion.Property;import org.hibernate.criterion.Restrictions;import org.junit.Test;import com.qfedu.hibernate.pojo.Customer;import com.qfedu.hibernate.pojo.Order;import com.qfedu.hibernate.utils.HibernateUtil;/** *  * @author helen * 1、全表查询 * 2、条件查询 * 3、分页查询 * 4、查询排序 * 5、聚合查询 * 6、投影查询 */public class OBCTest {    /**     * 全表查询     */    @Test    public void test1() {        Session session = HibernateUtil.openSession();        Transaction tx = session.beginTransaction();        Criteria ce = session.createCriteria(Customer.class);        List<Customer> list = ce.list();        for(Customer customer : list) {            System.out.println(customer);        }        tx.commit();        session.close();    }    /**     * 条件查询     */    @Test    public void test21() {        Session session = HibernateUtil.openSession();        Transaction tx = session.beginTransaction();        Criteria ce = session.createCriteria(Order.class);        ce.add(Restrictions.eq("orderno", "20170928001"));        List<Order> list = ce.list();        for(Order order : list) {            System.out.println(order);        }        tx.commit();        session.close();    }    /**     * 多条件查询     */    @Test    public void test22() {        Session session = HibernateUtil.openSession();        Transaction tx = session.beginTransaction();        Criteria ce = session.createCriteria(Order.class);        //ce.add(Restrictions.eq("orderno", "20170928001"));        ce.add(Restrictions.and(                  Restrictions.like("orderno", "%2017%"), Restrictions.like("productName", "%手机%")              ));        List<Order> list = ce.list();        for(Order order : list) {            System.out.println(order);        }        tx.commit();        session.close();    }    /**     * 分页查询     */    @Test    public void test3() {        Session session = HibernateUtil.openSession();        Transaction tx = session.beginTransaction();        Criteria ce = session.createCriteria(Order.class);        //分页        ce.setFirstResult(0);        ce.setMaxResults(5);        List<Order> list = ce.list();        for(Order order : list) {            System.out.println(order);        }        tx.commit();        session.close();    }    /**     * 查询排序     */    @Test    public void test4() {        Session session = HibernateUtil.openSession();        Transaction tx = session.beginTransaction();        Criteria ce = session.createCriteria(Order.class);        ce.addOrder(org.hibernate.criterion.Order.desc("id"));        List<Order> list = ce.list();        for(Order order : list) {            System.out.println(order);        }        tx.commit();        session.close();    }    /**     * 聚合排序     */    @Test    public void test5() {        Session session = HibernateUtil.openSession();        Transaction tx = session.beginTransaction();        Criteria ce = session.createCriteria(Order.class);        /*ce.setProjection(Projections.rowCount());        Long count = (Long)ce.uniqueResult();*/        ce.setProjection(Projections.max("id"));        Integer count = (Integer)ce.uniqueResult();        System.out.println(count);        tx.commit();        session.close();    }    /**     * 投影查询     */    @Test    public void test6() {        Session session = HibernateUtil.openSession();        Transaction tx = session.beginTransaction();        Criteria ce = session.createCriteria(Order.class);        ProjectionList pList = Projections.projectionList();        pList.add(Property.forName("orderno"));        pList.add(Property.forName("productName"));        ce.setProjection(pList);        List<Object[]> list = ce.list();        for(Object[] order : list) {            for(Object column : order) {                System.out.print(column);                System.out.print(" ");            }            System.out.println();        }        tx.commit();        session.close();    }}