hibernate_Restrictions用法
| 方法 |
说明 |
| Restrictions.eq |
＝ |
| Restrictions.allEq |
利用Map来进行多个等于的限制 |
| Restrictions.gt |
＞ |
| Restrictions.ge |
＞＝ |
| Restrictions.lt |
＜ |
| Restrictions.le |
＜＝ |
| Restrictions.between |
BETWEEN |
| Restrictions.like |
LIKE |
| Restrictions.in |
in |
| Restrictions.and |
and |
| Restrictions.or |
or |
| Restrictions.sqlRestriction |
用SQL限定查询 |
有空再添加上，代码示例。
QBC常用限定方法
Restrictions.eq-->equal,等于.
Restrictions.allEq-->参数为Map对象,使用key/value进行多个等于的比对,相当于多个Restrictions.eq的效果
Restrictions.gt-->great-than>大于
Restrictions.ge-->great-equal>=大于等于
Restrictions.lt-->less-than,<小于
Restrictions.le-->less-equal<=小于等于
Restrictions.between-->对应SQL的between子句
Restrictions.like-->对应SQL的LIKE子句
Restrictions.in-->对应SQL的in子句
Restrictions.and-->and关系
Restrictions.or-->or关系
Restrictions.isNull-->判断属性是否为空,为空则返回true
Restrictions.isNotNull-->与isNull相反
Restrictions.sqlRestriction-->SQL限定的查询
Order.asc-->根据传入的字段进行升序排序
Order.desc-->根据传入的字段进行降序排序
MatchMode.EXACT-->字符串精确匹配.相当于"like'value'"
MatchMode.ANYWHERE-->字符串在中间匹配.相当于"like'%value%'"
MatchMode.START-->字符串在最前面的位置.相当于"like'value%'"
MatchMode.END-->字符串在最后面的位置.相当于"like'%value'"
例子
查询年龄在20-30岁之间的所有学生对象
Listlist=session.createCriteria(Student.class)
.add(Restrictions.between("age",newInteger(20),newInteger(30)).list();
查询学生姓名在AAA,BBB,CCC之间的学生对象
String[]names={"AAA","BBB","CCC"};
Listlist=session.createCriteria(Student.class)
.add(Restrictions.in("name",names)).list();
查询年龄为空的学生对象
Listlist=session.createCriteria(Student.class)
.add(Restrictions.isNull("age")).list();
查询年龄等于20或者年龄为空的学生对象
Listlist=session.createCriteria(Student.class)
.add(Restrictions.or(Restrictions.eq("age",newInteger(20)),
Restrictions.isNull("age")).list();
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使用QBC实现动态查询
publicListfindStudents(Stringname,intage){
Criteriacriteria=session.createCriteria(Student.class);
if(name!=null){
criteria.add(Restrictions.liek("name",name,MatchMode.ANYWHERE));
}
if(age!=0){
criteria.add(Restrictions.eq("age",newInteger(age)));
}
criteria.addOrder(Order.asc("name"));//根据名字升序排列
returncriteria.list();
}
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今天用了写hibernate高级查询时用了Restrictions(当然Expression也是可以以的)这个类.感觉不错.
下面的代码写的不易读.其实核心就是一句
Restrictions.or(Restrictions.like(),Restrictions.or(Restrictions.like,........))
里面的or可以无限加的.还是比较好用
Sessionsession=getHibernateTemplate().getSessionFactory()
.openSession();
Criteriacriteria=session.createCriteria(Film.class);
List<Film>list=criteria.add(
Restrictions.or(Restrictions.like("description",key,MatchMode.ANYWHERE),
Restrictions.or(Restrictions.like("name",key,MatchMode.ANYWHERE),
Restrictions.or(Restrictions.like("direct",key,MatchMode.ANYWHERE),
Restrictions.or(Restrictions.like("mainplay",key,MatchMode.ANYWHERE),
Restrictions.like("filearea",key,MatchMode.ANYWHERE)))))).list();
session.close();
returnlist;