Hibernate中使用Criteria查询及注解——（DeptTest.java）-阿里云开发者社区

DeptTest.java

测试类：

先创建Session：

private Session session;
  private Transaction tx;
  @Before
  public void beforeMethod(){
    
    session=new Configuration()
          .configure()
          .buildSessionFactory()
          .openSession();
  }

关闭Session：

@After
  public void afterMethod() {
    if (session != null) {
      session.close();
    }
  }

开始测试：

/**
* 测试简单查询
*/

@Test
  public void testMethod1() {
    
    //查询所有的部门
    Criteria criteria=session.createCriteria(Dept.class);
    List<Dept> deptList=criteria.list();
    for (Dept dept : deptList) {
      System.out.println("部门编号："+dept.getDeptno());
      System.out.println("部门名称："+dept.getDname());
      System.out.println("部门编地址："+dept.getLoc());
    }
  }

查詢部门在山西吕梁的部门名称

//查询部门地址在山西吕梁的部门名称
  @Test
  public void test2(){
    List<Dept> deptList=session.createCriteria(Dept.class)
              .add(Restrictions.eq("loc", "山西吕梁")).list();
    for (Dept dept : deptList) {
      System.out.println(dept.getDeptno()+","+dept.getDname());
    }
  }

//查询工资高于5000的员工

@Test
  public void test3(){
    List<Emp> empList=session
                .createCriteria(Emp.class)
                .add(Restrictions.gt("sal", 5000D)).list();
    for (Emp emp : empList) {
      System.out.println(emp.getEname()+","+emp.getSal());
    }
  }

//查询不属于任何部门的员工

@Test
  public void test4(){
    List<Emp> empList=session.createCriteria(Emp.class)
                         .add(Restrictions.isNull("dept")).list();
    for (Emp emp : empList) {
      System.out.println(emp.getEname());
    }
  }

//查询职位是CLERK的员工

//ignoreCase:不区分大小写

@Test
  public void test5(){
    List<Emp> empList=session.createCriteria(Emp.class)
                         .add(Restrictions.eq("job","ClERK").ignoreCase())
                         .list();
    for (Emp emp : empList) {
      System.out.println(emp.getEname()+","+emp.getDept().getDname());
    }
  }

/**

* in:等于列表中的某一个值

* not in:不等于列表中的任何一个值

* between 值1 and 值2：大于等于值1并且小于值2

* not between 值1 and 值2：小于值1或者大于值2

//查询职位是ANALYST 或 SALESMAN 的员工

@Test
  public void test6(){
    List jobList=new ArrayList();
    jobList.add("SALESMAN");
    jobList.add("ANALYST");
    List<Emp> empoList=session.createCriteria(Emp.class)
                           .add(Restrictions.in("job",jobList))
                           .list();
    for (Emp emp : empoList) {
      System.out.println(emp.getEname()+","+emp.getJob());
    }
  }

//查询工资在2000元到4000元的员工

@Test
  public void test7(){
    List<Emp> empList=session.createCriteria(Emp.class)
                         .add(Restrictions.between("sal", 2000D, 4000D))
                         .list();
    for (Emp emp : empList) {
      System.out.println(emp.getEname()+","+emp.getSal());
    }
  }

/**

* like:字符串模式匹配

* ilike：字符串木事匹配，忽略大小写

//查询姓名中包括s的职位(like)

@Test
  public void test8(){
    List<Emp> empList=session.createCriteria(Emp.class)
                          .add(Restrictions.like("job","%s%"))
                          .list();
    for (Emp emp : empList) {
      System.out.println(emp.getEname());
    }
  }

//查询姓名中包括s的职位(ilike)

@Test
    public void test9(){
      List<Emp> empList=session.createCriteria(Emp.class)
                            .add(Restrictions.ilike("job","%s%"))
                            .list();
      for (Emp emp : empList) {
        System.out.println(emp.getEname());
      }
    }

/**

* MatchMode静态常量

* 1.MatchMode.STRART: 员工姓名以s开头

* 2.MatchMode.END：员工姓名以s结尾

* 3.MatchMode.ANYWHERE 员工姓名中包含s

* 4.MatchMode.EXACT 员工姓名中等于s精确匹配

//查询职位中包括s的职位

@Test
    public void test10(){
      List<Emp> empList=session.createCriteria(Emp.class)
                            .add(Restrictions.ilike("job","%s%",MatchMode.ANYWHERE))
                            .list();
      for (Emp emp : empList) {
        System.out.println(emp.getJob());
      }
    }

/**

*逻辑运算

*1.and:逻辑与

*2.or:逻辑或

*3.not:逻辑非

//查询职位是accountant 或者是analyert的职位名称

@Test
    public void test11(){
      List<Emp> empList=session.createCriteria(Emp.class)
                            .add(Restrictions.or(Restrictions.eq("job", "analyert").ignoreCase(),
                                 Restrictions.eq("job","accountant").ignoreCase()))
                            .list();
      for (Emp emp : empList) {
        System.out.println(emp.getJob());
      }
    }

//查询职位是accountant 或者是analyert 或者是 engineer的职位名称

@Test
      public void test12(){
        List<Emp> empList=session.createCriteria(Emp.class)
                                   .add(Restrictions.disjunction()
                                 .add(Restrictions.eq("job", "analyert").ignoreCase())
                                   .add(Restrictions.eq("job","accountant").ignoreCase())
                                   .add(Restrictions.eq("job", "engineer").ignoreCase()))
                                   .list();
        for (Emp emp : empList) {
          System.out.println(emp.getJob());
        }
      }

/**

* 集合运算符

* 1. is empty:集合为空，不包含任何元素

* 2. is not empty：集合不为空

//查询没有员工的部门

@Test
      public void test13(){
        List<Dept> deptList=session.createCriteria(Dept.class)
                             .add(Restrictions.isEmpty("emps"))
                             .list();
        for (Dept dept : deptList) {
          System.out.println(dept.getDname());
        }
      }

/**

* 动态查询

* 条件见下：（条件类：EmpCondition）

* 1.job是engineer

* 2.sal大于2000

* 3.入职时间在2006年12月31日到2008年12月31日之前

@Test
    public void test14(){
      SimpleDateFormat format=new SimpleDateFormat("yyyy-MM-dd");
      EmpCondition empCondition=new EmpCondition();
      try {
        empCondition.setJob("engineer");
        empCondition.setSal(2000D);
        String hiredateStart="2006-12-31";
        String hiredateEnd="2008-12-31";
        Date hiredateStart1=format.parse(hiredateStart);
        Date hiredateEnd1=format.parse(hiredateEnd);
        empCondition.setHiredateStart(hiredateStart1);
        empCondition.setHiredateEnd(hiredateEnd1);
        
      } catch (ParseException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
      }

//添加动态查询的条件

Criteria criteria=session.createCriteria(Emp.class);
      if(empCondition.getJob()!=null){
        criteria.add(Restrictions.ilike("job", empCondition.getJob()));
      }
      if(empCondition.getSal()!=null){
        criteria.add(Restrictions.gt("sal",empCondition.getSal()));
      }
      if(empCondition.getHiredateStart()!=null){
        criteria.add(Restrictions.ge("hiredate",empCondition.getHiredateStart()));
      }
      if(empCondition.getHiredateEnd()!=null){
        criteria.add(Restrictions.le("hiredate",empCondition.getHiredateEnd()));
      }
//输出
            List<Emp>emplist=criteria.list();
            for (Emp emp : emplist) {
                System.err.println(emp.getEname()+","+emp.getJob()+","+emp.getSal()+","+emp.getHiredate());
            }
        }

/**

* 分页查询

//分页查询部门是SALESMAN 的所有员工

//并且工资降序

//显示总页数，总记录数，当前页号

@Test
    public void test15(){
      Criteria criteria =session.createCriteria(Emp.class)
                            .add(Restrictions.eq("job", "SALESMAN").ignoreCase())
                            .setProjection(Projections.count("empno"));
      //获得总记录数
      Integer count=(Integer)criteria.uniqueResult();
      //分页
      int pageSize=2;
      int pageIndex=1;
      int totalPage=count%pageSize==0?count/pageSize:(count/pageSize)+1;
      criteria=session.createCriteria(Emp.class)
                  .add(Restrictions.eq("job", "SALESMAN").ignoreCase())
                  .addOrder(Order.desc("sal"));
      //开始分页，设置从哪条记录开始查
      List<Emp> emplist=criteria.setFirstResult((pageIndex-1)*pageSize)
                            .setMaxResults(pageSize)
                            .list();
      
      for (Emp emp : emplist) {
        System.out.println(emp.getEname()+","+emp.getSal());
      }
      System.out.println("总页数:"+totalPage);
      System.err.println("总记录数："+count);
      System.out.println("当前页号："+pageIndex);
    
    }

/**

* 连接查询

* Criteria里面只有内连接和迫切做外链接

//查询RESEARCH部们中姓名包括s的员工

@Test
    public void test16(){
      List<Emp> emplistList=session.createCriteria(Emp.class)
                               .add(Restrictions.ilike("ename", "s",MatchMode.ANYWHERE))
                               .createCriteria("dept")
                               .add(Restrictions.eq("dname","RESEARCH").ignoreCase())
                               .list();
      for (Emp emp : emplistList) {
        System.out.println(emp.getEname()+","+emp.getDept().getDname());
      }
    }
    
    //查询RESEARCH部门中姓名包含s的员工
    @Test
    public void test17(){
      List<Emp> empList=session.createCriteria(Emp.class,"e")
                           .createAlias("dept", "d")
                           .add(Restrictions.ilike("e.ename","s",MatchMode.ANYWHERE))
                           .add(Restrictions.eq("d.dname","RESEARCH").ignoreCase())
                           .list();
      for (Emp emp : empList) {
        System.out.println(emp.getEname()+","+emp.getDept().getDname());
      }
    }

//左外连接

//查询位置在山西吕梁的部门及其人数

//FetchMode.JOIN表示迫切做外链接查询策略

@Test
    public void test18(){
      List<Dept> deptList=session.createCriteria(Dept.class,"d")
                             .setFetchMode("emps",FetchMode.JOIN)
                             .add(Restrictions.eq("d.loc","山西吕梁").ignoreCase())
                             .list();
      for (Dept dept : deptList) {
        System.out.println(dept.getDname()+","+dept.getLoc()+","+dept.getEmps().size());
      }
    }

//去掉重复数据

@Test
    public void test19(){
    List<Dept> deptList=session.createCriteria(Dept.class,"d")
                           .setFetchMode("emps", FetchMode.JOIN)
                           .add(Restrictions.eq("d.loc","山西吕梁").ignoreCase())
                           .list();
    HashSet<Dept> set=new HashSet<Dept>(deptList);
    for (Dept dept : set) {
      System.out.println(dept.getDname()+","+dept.getLoc()+","+dept.getEmps().size());
    }
    
    }

/**

* 投影，分组，及DetachedCriteria

//查询所有的部门名称】

@Test
    public void test20(){
      List<String> list=session.createCriteria(Dept.class)
                            .setProjection(Property.forName("dname"))
                            .list();
      for (String str : list) {
        System.out.println(str);
      }
    }

//查询两个或者两个以上的属性

//查询员工的姓名和入职时间

@Test
    public void test21(){
      List<Object[]> list=session.createCriteria(Emp.class)
                             .setProjection(
                                   Projections.projectionList()
                                   .add(Property.forName("ename"))
                                   .add(Property.forName("hiredate"))
                                 )
                                .list();
      
      for (Object[] objects : list) {
        System.out.println(objects[0]+","+objects[1]);
      }
                             
    }

/**

* 分组

* 1.groupProperty:分组

* 2.rowCount():统计记录数

* 3.avg:平均值

* 4.max:最大值

* 5.min:最小值

* 6.count:统计某一字段的非空记录数

* 7.sum:针对某一字段进行求和

//统计各个部门的平均工资，最高工资，最低工资

@Test
    public void test22(){
      List<Object[]> list=session.createCriteria(Emp.class,"e")
                             .createAlias("e.dept", "d")
                             .setProjection(
                                 Projections.projectionList()
                                 .add(Projections.groupProperty("d.dname"))
                                 .add(Projections.avg("e.sal"))
                                 .add(Projections.max("e.sal"))
                                 .add(Projections.min("e.sal"))
                                 )
                                 .list();
      for (Object[] objects : list) {
        System.out.println("部门名称"+objects[0]+",最高工资："+objects[2]+"" +
            ",平均工资："+objects[1]+",最低工资："+objects[3]);
      }
                             
    }

//使用DetachedCriteria

//查询RESEARCH部门，姓名包含“a”的员工

@Test
    public void test23(){
      DetachedCriteria detachedCriteria
                 =DetachedCriteria.forClass(Emp.class,"e")
                     .createAlias("e.dept","d")
                     .add(Restrictions.eq("d.dname","RESEARCH").ignoreCase())
                     .add(Restrictions.ilike("e.ename","a",MatchMode.ANYWHERE));
      List<Emp> list=detachedCriteria.getExecutableCriteria(session).list();
      for (Emp emp : list) {
        System.out.println(emp.getEname()+","+emp.getDept().getDname());
      }
                                  
    }

//查询工资高于平均工资的员工

@Test
    public void test24(){
      //平均工资
      DetachedCriteria detachedCriteria=DetachedCriteria
                       .forClass(Emp.class,"e")
                       .setProjection(Property.forName("sal").avg());
      //求工资大于平均工资
      List<Emp> emplist=session.createCriteria(Emp.class)
                           .add(Property.forName("sal").gt(detachedCriteria)).list();
      for (Emp emp : emplist) {
        System.out.println(emp.getEname()+","+emp.getSal());
      }
      
    }

Hibernate中使用Criteria查询及注解——（DeptTest.java）

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