HQL的参数绑定

按参数位置绑定 setXXX()方法第一个参数从0下标开始

 public List<Emp> selectEmp(String job,double salary)
    {
        String hql="select emp from Emp as emp where emp.job=? and emp.salary>?";
        return this.getCurrentSession().createQuery(hql)
                .setString(0,job)
                .setDouble(1,salary)
                .list();
    }

Hibernate:
select
emp0_.empNo as empNo1_,
emp0_.empName as empName1_,
emp0_.job as job1_,
emp0_.salary as salary1_
from
project.Emp emp0_
where
emp0_.job=?
and emp0_.salary>?

按参数名称绑定 命名参数以":"开头而且setXXX()方法第一个参数和:后面的字符串对应

String hql="select emp from Emp as emp where emp.job=:job and emp.salary>:salary";
        return this.getCurrentSession().createQuery(hql)
                .setString("job",job)
                .setDouble("salary",salary)
                .list();

Hibernate:
select
emp0_.empNo as empNo1_,
emp0_.empName as empName1_,
emp0_.job as job1_,
emp0_.salary as salary1_
from
project.Emp emp0_
where
emp0_.job=?
and emp0_.salary>?

Hibernate提供setParameter()方法用来绑定任意类型的参数，当不便指定参数的具体类型时，可以使用setParameter()为参数赋值

 public List<Emp> selectEmp(Object[] condition)
    {
        String hql="select emp from Emp as emp where emp.job=? and emp.salary>?";
        Query query=this.getCurrentSession().createQuery(hql);
        if (condition!=null&&condition.length>0)
        {
            for (int i=0;i<condition.length;i++)
            {
                query.setParameter(i,condition[i]);
            }
        }
        return query.list();
    }

Hibernate:
select
emp0_.empNo as empNo1_,
emp0_.empName as empName1_,
emp0_.job as job1_,
emp0_.salary as salary1_
from
project.Emp emp0_
where
emp0_.job=?
and emp0_.salary>?

public List<Emp> selectEmp(Map<String, Object> conditions) {
        String hql = "select emp from Emp as emp where emp.job=:job and emp.salary>:salary";
        Query query = this.getCurrentSession().createQuery(hql);
        if (conditions != null && conditions.size() > 0) {
           /* Iterator<Map.Entry<String, Object>> iter = conditions.entrySet().iterator();
            while (iter.hasNext()) {
                Map.Entry<String, Object> entry = iter.next();
                String key = entry.getKey();
                Object value = entry.getValue();
                query.setParameter(key, value);
            }*/
           /* for (String key : conditions.keySet()) {
                query.setParameter(key, conditions.get(key));
            }*/
            for (Map.Entry<String, Object> entry : conditions.entrySet()) {
                query.setParameter(entry.getKey(), entry.getValue());
            }
           /* Iterator<String> iterator = conditions.keySet().iterator();
            while (iterator.hasNext()) {
                String key = iterator.next();
                Object value = conditions.get(key);
                query.setParameter(key, value);
            }*/
        }
        return query.list();
    }

Hibernate:
select
emp0_.empNo as empNo1_,
emp0_.empName as empName1_,
emp0_.job as job1_,
emp0_.salary as salary1_
from
project.Emp emp0_
where
emp0_.job=?
and emp0_.salary>?

setProperties()方法绑定命名参数与一个对象的属性值(命名参数要和属性值对应)

package com.dto;

public class EmpForm {
    private String job;
    private double salary;

    public String getJob() {
        return job;
    }

    public void setJob(String job) {
        this.job = job;
    }

    public double getSalary() {
        return salary;
    }

    public void setSalary(double salary) {
        this.salary = salary;
    }

    public EmpForm() {

    }

    public EmpForm(String job, double salary) {
        this.job = job;
        this.salary = salary;
    }

    @Override
    public String toString() {
        return "EmpForm{" +
                "job='" + job + '\'' +
                ", salary=" + salary +
                '}';
    }
}

public List<Emp> selectEmp(EmpForm empForm)
      {
          String hql="select emp from Emp emp where emp.job=:job and emp.salary>=:salary";
          Query query=this.getCurrentSession().createQuery(hql);
          query.setProperties(empForm);
          return query.list();
      }

Hibernate:
select
emp0_.empNo as empNo1_,
emp0_.empName as empName1_,
emp0_.job as job1_,
emp0_.salary as salary1_
from
project.Emp emp0_
where
emp0_.job=?
and emp0_.salary>=?

动态设置查询参数 根据用户实际输入的参数确定查询条件

  public List<Emp> selectEmp(EmpForm empForm) {
        StringBuilder hql = new StringBuilder("select emp from Emp emp where 1=1");
        if (empForm.getJob() != null && empForm.getJob().length() > 0) {

            hql.append(" and emp.job=:job");
        }
        if (empForm.getSalary() > 0) {
            hql.append(" and emp.salary>=salary");
        }
        Query query = this.getCurrentSession().createQuery(hql.toString());
        query.setProperties(empForm);
        return query.list();
    }

Hibernate:
select
emp0_.empNo as empNo1_,
emp0_.empName as empName1_,
emp0_.job as job1_,
emp0_.salary as salary1_

from
    project.Emp emp0_ 
where
    1=1 
    and emp0_.job=?