hibernate09--连接查询

package cn.bdqn.bean;

import java.util.ArrayList;
import java.util.Date;
import java.util.List;

/**
 * @author 小豆腐
 *
 *员工的实体类
 */
public class Emp {

    private Integer empNo; 
    private String empName;
    private String job;
    private Double salary;
    private Date hireDate;
    
    //多个员工属于一个部门
    private  Dept dept;

    public Integer getEmpNo() {
        return empNo;
    }

    public void setEmpNo(Integer empNo) {
        this.empNo = empNo;
    }

    public String getEmpName() {
        return empName;
    }

    public void setEmpName(String empName) {
        this.empName = empName;
    }

    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 Date getHireDate() {
        return hireDate;
    }

    public void setHireDate(Date hireDate) {
        this.hireDate = hireDate;
    }

    public Dept getDept() {
        return dept;
    }

    public void setDept(Dept dept) {
        this.dept = dept;
    }

    public Emp(Integer empNo, String empName, String job, Double salary,
            Date hireDate, Dept dept) {
        super();
        this.empNo = empNo;
        this.empName = empName;
        this.job = job;
        this.salary = salary;
        this.hireDate = hireDate;
        this.dept = dept;
    }

    public Emp() {
        super();
    }

    @Override
    public String toString() {
        return "Emp [empNo=" + empNo + ", empName=" + empName + ", job=" + job
                + ", salary=" + salary + ", hireDate=" + hireDate + ", dept="
                + dept + "]";
    }
}

package cn.bdqn.bean;

import java.util.HashSet;
import java.util.Set;

import com.sun.org.apache.bcel.internal.generic.NEW;

/**
 * 
 *  部门的实体类
 */
public class Dept {
    
    private  Integer  deptNo;
    private  String  deptName;
    private  String  location;  
    //一个部门对应多个员工
    private  Set emps=new HashSet();
    public Integer getDeptNo() {
        return deptNo;
    }
    public void setDeptNo(Integer deptNo) {
        this.deptNo = deptNo;
    }
    public String getDeptName() {
        return deptName;
    }
    public void setDeptName(String deptName) {
        this.deptName = deptName;
    }
    public String getLocation() {
        return location;
    }
    public void setLocation(String location) {
        this.location = location;
    }
    public Set getEmps() {
        return emps;
    }
    public void setEmps(Set emps) {
        this.emps = emps;
    }
    public Dept(Integer deptNo, String deptName, String location, Set emps) {
        super();
        this.deptNo = deptNo;
        this.deptName = deptName;
        this.location = location;
        this.emps = emps;
    }
    public Dept() {
        super();
    }
    @Override
    public String toString() {
        return "Dept [deptNo=" + deptNo + ", deptName=" + deptName
                + ", location=" + location + ", emps=" + emps.size() + "]";
    }
    
    
    
    
}

public class EmpTest {
    Session session =null;
    Transaction transaction=null;
    
    @Before
    public  void  before(){
         session = HibernateSessionUtil.getCurrentSession();
         transaction= session.beginTransaction();
    }
    
    /**
     * 先给两个表中 增加测试数据
     */
    @Test
    public  void  testAdd(){
        /**
         * 因为我们设置了级联操作 cascade=all
         * 那么我们就可以在保存部门信息的时候保存员工
         */
        Dept dept=new Dept();
        dept.setDeptNo(2);
        dept.setDeptName("市场部");
        dept.setLocation("2楼");
        //创建员工
        Emp emp1=new Emp(5, "员工5", "程序猿5", 5000.0,dept);
        Emp emp2=new Emp(6, "员工6", "程序猿6", 545000.0,dept);
        Emp emp3=new Emp(7, "员工7", "程序猿7", 2000.0,dept);
        Emp emp4=new Emp(8, "员工8", "程序猿8", 98000.0,dept);
        Set emps=new HashSet();
        emps.add(emp1);
        emps.add(emp2);
        emps.add(emp3);
        emps.add(emp4);
        dept.setEmps(emps);  //把所有的员工放入了集合中
        session.save(dept);
        transaction.commit();
    }
    
    
    /**
     *  所有的迫切连接返回的都是一个对象！     有fetch===》迫切连接
     *  所有的非迫切连接返回的都是一个数组！
     *  
     *  
     *  01.使用内连接查询  两个表的所有数据
     *  sql语句
     *  select * from emp inner join dept 
          on dept.deptno=emp.deptno
        
        hql语句
        from Emp e inner join e.dept(Emp类中的关联属性名)
     */
    @Test
    public  void  test01(){
        String hql="from Emp e inner join e.dept";
         List