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6Hibernate进阶----青软S2SH(笔记)
关于关联关系的配置,用注解配置如下(这里引用的jar包是javax.persistence)
// @ManyToOne(fetch=FetchType.LAZY) @ManyToOne(fetch=FetchType.EAGER) @JoinColumn(name="supplier_id",nullable=true) private Supplier supplier;
用xml文件配置如下,这个跟注解配置有些不同,就不详解了,反正我也不会用xml配置
例子
/* 使用HQL对查询结果按照Customer的userName进行降序排序 */ public static void orderByUserNameByDesc_HQL() { // 1.获取session对象 Session session = HibernateUtils.getSession(); // 2.编写hql语句 String hql = "from Customer c order by c.userName desc"; // 3.以HQL作为参数,调用session的createQuery()方法创建Query对象 Query query = session.createQuery(hql); // 4.调用query对象的list()等方法遍历结果 List<Customer> list = query.list(); // 打印结果 for (Customer c : list) { System.out.println(c.getId() + "\t" + c.getUserName()); } }
一个使用hql来进行动态查询的使用方法(用map存储参数)
@SuppressWarnings("unchecked")public long getXXXCount(Map<String,String> conditions) throws Exception { String hql = "select count(u.id)"; Map<String,Object> valMap = createPartHql(hql,conditions); hql = (String)valMap.get("hql"); valMap.remove("hql"); Query query = getQueryFromMapAndHql(valMap,hql); return (long)query.list().get(0); } private static Map<String,Object> createPartHql(String hql,Map<String,String> conditions){ Map<String,Object> valMap = new HashMap<>(); boolean conditionsIsNull = true; for(Map.Entry<String, String> entry:conditions.entrySet()){ if(StringUtils.isNotEmpty(entry.getValue())) conditionsIsNull = false; }
hql = hql+" from xxxx u where u.deleteFlg = 0";
if(StringUtils.isNotEmpty(conditions.get("roleType"))){
hql = hql+" and u.roleType = :roleType";
valMap.put("roleType", Integer.parseInt(conditions.get("roleType")));
}
if(StringUtils.isNotEmpty(conditions.get("loginId"))){
hql = hql+" and u.loginId like :loginId";
valMap.put("loginId", "%"+conditions.get("loginId")+"%");
}
valMap.put("hql", hql); return valMap; } --------------------------- public Query getQueryFromMapAndHql(Map<String,Object> FieldsMap,String hql){ Query query = this.getSessionFactory().getCurrentSession().createQuery(hql); for(Map.Entry<String, Object> entry : FieldsMap.entrySet()){ query.setParameter(entry.getKey(), entry.getValue()); } return query; } public Query getQueryFromMapAndHql(Map<String,String> FieldsMap,Query query){ for(Map.Entry<String, String> entry : FieldsMap.entrySet()){ query.setParameter(entry.getKey(), entry.getValue()+""); } return query; }
其他示例:
package com.qst.chapter06.demo; import java.text.ParseException; import java.text.SimpleDateFormat; import java.util.HashSet; import java.util.List; import org.hibernate.Criteria; import org.hibernate.Query; import org.hibernate.Session; import org.hibernate.criterion.DetachedCriteria; import org.hibernate.criterion.Example; import org.hibernate.criterion.MatchMode; import org.hibernate.criterion.Restrictions; import com.qst.chapter06.pojos.Customer; import com.qst.chapter06.pojos.Order; import com.qst.chapter06.pojos.Product; import com.qst.chapter06.util.HibernateUtils; public class HqlCriteriaBusinessDemo { public static void main(String[] args) { // findCustomersByAddress_HQL("青岛市"); // findCustomersByAddress_QBC("青岛市"); // orderByUserNameByDesc_HQL(); // orderByUserNameByDesc_QBC(); // 第2页,每页3条记录 // List<Customer> list=listPageCustomer_HQL(2,3); // List<Customer> list = listPageCustomer_QBC(2, 3); // 打印结果 // for (Customer c : list) { // System.out.println(c.getId() + "\t" + c.getUserName()); // } // Customer c = findOneCustomer_HQL(); // Customer c = findOneCustomer_QBC(); // System.out.println(c.getId() + "\t" + c.getUserName()); // List<Customer> list=findCustomersByName1("zhangsan1"); // List<Customer> list=findCustomersByName2("zhangsan1"); // //打印结果 // for (Customer c : list) { // System.out.println(c.getId() + "\t" + c.getUserName()); // } // findCustomerByJoin(); // findCustomerByFetchJoin(); // findCustomerByLeftJoin(); // findCustomerByLeftFetch(); // groupByCustomer(); // printOrders_HQL(); // printOrders_QBC(); // ////////////////////////////////////////////// // List<Product> listProduct = findProductsByHQL("打印机", 560.0); // List<Product> listProduct = findProductsByCriteria("打印机", 560.0); // List<Product> listProduct= findProductsByQBE(product); // Product product=new Product(); // product.setName("打印机"); // product.setPrice(560.0); // ////////////////////////////////////////////// // DetachedCriteria cri = DetachedCriteria.forClass(Product.class); // // 根据用户的动态查询条件,创建DetachedCriteria对象 // cri.add(Restrictions.ilike("name", "打印机", MatchMode.ANYWHERE)); // cri.add(Restrictions.eq("price", 560.0)); // List<Product> listProduct = findProducts(cri); // for (Product p : listProduct) { // System.out.println(p.getId() + "\t" + p.getName() + "\t" // + p.getPrice() + "\t" + p.getDescription()); // } ///////////////////////////////////////////////////////////// findProductsBySubQuerys(); } /* 使用HQL检索根据地址查询Customer */ public static void findCustomersByAddress_HQL(String address) { // 1.获取session对象 Session session = HibernateUtils.getSession(); // 2.编写hql语句 String hql = "from Customer c where c.address = :address"; // // 3.以HQL作为参数,调用session的createQuery()方法创建Query对象 // Query query = session.createQuery(hql); // // 4.调用Query对象的setXXX()方法为参数赋值 // query.setString("address", address); // // 5.调用Query对象的list()等方法得到查询结果 // List<Customer> list = query.list(); // Query对象匿名方式 List<Customer> list = session.createQuery(hql) .setString("address", address).list(); // 遍历输出结果 for (Customer c : list) { System.out.println(c.getId() + "\t" + c.getUserName()); } } /* 使用QBC检索根据地址查询Customer */ public static void findCustomersByAddress_QBC(String address) { // 1.获取session对象 Session session = HibernateUtils.getSession(); // 2.以Customer的Class对象作为参数,创建Criteria对象 Criteria critera = session.createCriteria(Customer.class); // // 3.调用Criteria对象的add()方法,增加Criterion查询条件 // critera.add(Restrictions.eq("address", address)); // // 4.执行Criteria的list()方法返回查询结果 // List<Customer> list = critera.list(); // Criteria对象匿名方式 List<Customer> list = session.createCriteria(Customer.class) .add(Restrictions.eq("address", address)).list(); // 遍历输出结果 for (Customer c : list) { System.out.println(c.getId() + "\t" + c.getUserName()); } } /* 使用HQL对查询结果按照Customer的userName进行降序排序 */ public static void orderByUserNameByDesc_HQL() { // 1.获取session对象 Session session = HibernateUtils.getSession(); // 2.编写hql语句 String hql = "from Customer c order by c.userName desc"; // 3.以HQL作为参数,调用session的createQuery()方法创建Query对象 Query query = session.createQuery(hql); // 4.调用query对象的list()等方法遍历结果 List<Customer> list = query.list(); // 打印结果 for (Customer c : list) { System.out.println(c.getId() + "\t" + c.getUserName()); } } /* 使用QBC检索中的Order类对查询结果按照Customer的userName进行降序排序 */ public static void orderByUserNameByDesc_QBC() { // 1.获取session对象 Session session = HibernateUtils.getSession(); // 2.以Customer的Class对象作为参数,创建Criteria对象 Criteria critera = session.createCriteria(Customer.class); // 3.调用criteria对象的addOrder()方法条件排序规则 critera.addOrder(org.hibernate.criterion.Order.desc("userName")); List<Customer> list = critera.list(); // 打印结果 for (Customer c : list) { System.out.println(c.getId() + "\t" + c.getUserName()); } } /* 使用HQL分页查询Customer信息 */ public static List<Customer> listPageCustomer_HQL(int pageNo, int perPageNum) { Session session = HibernateUtils.getSession(); String hql = "from Customer c order by c.userName desc"; Query query = session.createQuery(hql); query.setFirstResult((pageNo - 1) * perPageNum); query.setMaxResults(perPageNum); List<Customer> list = query.list(); return list; } /* 使用QBC分页查询Customer信息 */ public static List<Customer> listPageCustomer_QBC(int pageNo, int perPageNum) { Session session = HibernateUtils.getSession(); Criteria criteria = session.createCriteria(Customer.class); criteria.setFirstResult((pageNo - 1) * perPageNum); criteria.setMaxResults(perPageNum); List<Customer> list = criteria.list(); return list; } /* 利用HQL检索单个Customer对象 */ public static Customer findOneCustomer_HQL() { Session session = HibernateUtils.getSession(); String hql = "from Customer c order by c.userName desc"; Customer customer = (Customer) session.createQuery(hql) .setMaxResults(1).uniqueResult(); return customer; } /* 利用QBC检索单个Customer对象 */ public static Customer findOneCustomer_QBC() { Session session = HibernateUtils.getSession(); Customer customer = (Customer) session.createCriteria(Customer.class) .addOrder(org.hibernate.criterion.Order.desc("userName")) .setMaxResults(1).uniqueResult(); return customer; } /* HQL检索3月份的订单对象 */ public static void printOrders_HQL() { Session session = HibernateUtils.getSession(); // HQL检索日期在指定范围之内 String hql = "from Order o where o.date between ? and ?"; // 创建一个日期格式类,用于格式化日期 SimpleDateFormat dateFormat = new SimpleDateFormat( "yyyy-MM-dd HH:mm:ss"); try { List<Order> list = session.createQuery(hql) .setParameter(0, dateFormat.parse("2015-03-01 00:00:00")) .setParameter(1, dateFormat.parse("2015-03-31 23:59:59")) .list(); // 打印结果 for (Order o : list) { System.out.println(o.getId() + "\t" + o.getDate()); } } catch (ParseException e) { // TODO Auto-generated catch block e.printStackTrace(); } } /* QBC检索3月份的订单对象 */ public static void printOrders_QBC() { Session session = HibernateUtils.getSession(); // 创建一个日期格式类,用于格式化日期 SimpleDateFormat dateFormat = new SimpleDateFormat( "yyyy-MM-dd HH:mm:ss"); try { // QBC检索 List<Order> list = session .createCriteria(Order.class) .add(Restrictions.between("date", dateFormat.parse("2015-03-01 00:00:00"), dateFormat.parse("2015-03-31 23:59:59"))).list(); // 打印结果 for (Order o : list) { System.out.println(o.getId() + "\t" + o.getDate()); } } catch (ParseException e) { // TODO Auto-generated catch block e.printStackTrace(); } } public static List<Customer> findCustomersByName1(String name) { // 获取Session对象 Session session = HibernateUtils.getSession(); // 创建HQL String hql = "from Customer as c where c.userName = :name"; Query query = session.createQuery(hql); // 按照参数名字进行绑定 query.setString("name", name); return query.list(); } public static List<Customer> findCustomersByName2(String name) { Session session = HibernateUtils.getSession(); String hql = "from Customer as c where c.userName = ?"; Query query = session.createQuery(hql); // 按照参数位置进行绑定 query.setString(0, name); return query.list(); } /* HQL内连接 */ public static void findCustomerByJoin() { Session session = HibernateUtils.getSession(); // 使用HQL进行内连接 String hql = "from Customer c inner join c.orders o where c.userName like :name"; Query query = session.createQuery(hql); query.setString("name", "z%"); List<Object[]> list = query.list(); for (Object[] objs : list) { Customer customer = (Customer) objs[0]; System.out.print(customer.getId() + " * " + customer.getUserName() + " * "); Order order = (Order) objs[1]; System.out.print(order.getOrderNo() + " * "); System.out.print(order.getDate()); System.out.println(); } } /* HQL预先抓取内连接 */ public static void findCustomerByFetchJoin() { Session session = HibernateUtils.getSession(); String hql = "from Customer c inner join fetch c.orders o where c.userName like :name"; Query query = session.createQuery(hql); query.setString("name", "z%"); List<Customer> list = query.list(); // 使用HashSet过滤重复元素 HashSet<Customer> set = new HashSet<Customer>(list); for (Customer customer : set) { System.out.print(customer.getId() + " " + customer.getUserName() + " "); for (Order order : customer.getOrders()) { System.out.print(order.getOrderNo() + " "); } System.out.println(); } } /* HQL左外连接 */ public static void findCustomerByLeftJoin() { Session session = HibernateUtils.getSession(); String hql = "from Customer c left outer join c.orders o where c.address = ?"; Query query = session.createQuery(hql); query.setString(0, "青岛市"); List<Object[]> list = query.list(); for (Object[] objs : list) { Customer customer = (Customer) objs[0]; System.out.print(customer.getId() + " " + customer.getUserName() + " "); Order order = (Order) objs[1]; if (objs[1] != null) System.out.print(order.getOrderNo()); System.out.println(); } } /* 预先抓取左外连接 */ public static void findCustomerByLeftFetch() { Session session = HibernateUtils.getSession(); String hql = "from Customer c left join fetch c.orders where c.address = ?"; Query query = session.createQuery(hql); query.setString(0, "青岛市"); List<Customer> list = query.list(); HashSet<Customer> set = new HashSet<Customer>(list); for (Customer customer : set) { System.out.print(customer.getId() + " " + customer.getUserName() + " "); for (Order order : customer.getOrders()) { System.out.print(order.getOrderNo() + " "); } System.out.println(); } } public static void groupByCustomer() { Session session = HibernateUtils.getSession(); String hql = "select c.userName,count(o) from Customer c left join c.orders o group by c.id"; Query query = session.createQuery(hql); List<Object[]> list = query.list(); for (Object[] objs : list) { String username = (String) objs[0]; Long count = (Long) objs[1]; System.out.println("用户名: " + username + " 订单数:" + count); } } public static List<Product> findProductsByHQL(String name, Double price) { Session session = HibernateUtils.getSession(); StringBuffer buffer = new StringBuffer(); // 生成基础SQL buffer.append("from Product p where 1=1"); // 如果name满足条件,则加入语句中 if (name != null) { buffer.append(" and lower(p.name) like :name"); } // 如果age满足条件,则加入语句中 if (price != null && price != 0) { buffer.append(" and p.price = :price"); } Query query = session.createQuery(buffer.toString()); if (name != null) { query.setString("name", "%" + name.toLowerCase() + "%"); } if (price != null && price != 0) { query.setDouble("price", price); } return query.list(); } public static List<Product> findProductsByCriteria(String name, Double price) { Session session = HibernateUtils.getSession(); Criteria criteria = session.createCriteria(Product.class); if (name != null) { criteria.add(Restrictions.ilike("name", name, MatchMode.ANYWHERE)); } if (price != null && price != 0) { criteria.add(Restrictions.eq("price", price)); } return criteria.list(); } public static List<Product> findProductsByQBE(Product product) { Session session = HibernateUtils.getSession(); /* customer为样本对象,根据查询条件创建的对象 */ Example example = Example.create(product)// 根据样本对象创建Example对象 .enableLike(MatchMode.ANYWHERE)// 对所有String类型的字段进行模糊匹配 .excludeNone()// 不把为空的字段加入where子句中 .excludeZeroes()// 不把值为0的字段加入where子句中 .ignoreCase();// 忽略所有String类型字段的大小写 Criteria criteria = session.createCriteria(Product.class); criteria.add(example); return criteria.list(); } // 在业务逻辑层 把DetachedCriteria对象与Session对象绑定,并返回查询结果 public static List<Product> findProducts(DetachedCriteria detachedCriteria) { Session session = HibernateUtils.getSession(); Criteria criteria = detachedCriteria.getExecutableCriteria(session); return criteria.list(); } public static void findProductsBySubQuerys() { Session session = HibernateUtils.getSession(); String hql = "from Product p where p.price=(select p1.price from Product p1 where p1.name=:name) and p.name!=:name"; Query query = session.createQuery(hql); query.setString("name", "打印机"); List<Product> list = query.list(); for (Product p : list) { System.out.println(p.getId() + "\t" + p.getName() + "\t" + p.getPrice() + "\t" + p.getDescription()); } } }
增加查询条件的方法如下
.add(Restrictions.eq("address", address))
/* 使用QBC检索中的Order类对查询结果按照Customer的userName进行降序排序 */ public static void orderByUserNameByDesc_QBC() { // 1.获取session对象 Session session = HibernateUtils.getSession(); // 2.以Customer的Class对象作为参数,创建Criteria对象 Criteria critera = session.createCriteria(Customer.class); // 3.调用criteria对象的addOrder()方法条件排序规则 critera.addOrder(org.hibernate.criterion.Order.desc("userName")); List<Customer> list = critera.list(); // 打印结果 for (Customer c : list) { System.out.println(c.getId() + "\t" + c.getUserName()); } }
/* 使用QBC检索根据地址查询Customer */ public static void findCustomersByAddress_QBC(String address) { // 1.获取session对象 Session session = HibernateUtils.getSession(); // 2.以Customer的Class对象作为参数,创建Criteria对象 Criteria critera = session.createCriteria(Customer.class); // // 3.调用Criteria对象的add()方法,增加Criterion查询条件 // critera.add(Restrictions.eq("address", address)); // // 4.执行Criteria的list()方法返回查询结果 // List<Customer> list = critera.list(); // Criteria对象匿名方式 List<Customer> list = session.createCriteria(Customer.class) .add(Restrictions.eq("address", address)).list(); // 遍历输出结果 for (Customer c : list) { System.out.println(c.getId() + "\t" + c.getUserName()); } }
6Hibernate进阶----青软S2SH(笔记)
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