hibernate12--注解

 在之前的基础上删除hbm.xml映射文件

之后修改实体类内容

/**
 *  部门的实体类
 *  strategy对应的就是主键生成策略
 *  GenerationType：
 *  01.auto:自动选择合适的策略，而且是默认值
 *  02.identity：主键自增
 *  03.sequence：通过序列产生主键
 *  04.table：通过表来生成主键！框架依赖数据库中的表！模拟序列产生主键！
 */
@Entity
public class Dept {
    @Id
    @GeneratedValue(strategy=GenerationType.AUTO)
    private  Integer  deptNo;
    private  String  deptName;
    @Transient   //忽略映射属性   输出值  null
    private  String  location;  
    //一个部门对应多个员工
    @OneToMany(mappedBy="dept",cascade={CascadeType.ALL})
    private  Set<Emp> 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<Emp> getEmps() {
        return emps;
    }
    public void setEmps(Set<Emp> emps) {
        this.emps = emps;
    }
    public Dept(Integer deptNo, String deptName, String location, Set<Emp> 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() + "]";
    }
    
    
    
    
}

 

/**
 * @author 小豆腐
 *员工的实体类
 */
@Entity
public class Emp {
@Id
@GeneratedValue(strategy=GenerationType.SEQUENCE,generator="seq_emp")
@SequenceGenerator(name="seq_emp",sequenceName="sq_student_id")    
    private Integer empNo; 
    private String empName;
    private String job;
    @Column(name="salary")
    private Double sal;
    private Date hireDate;
    //多个员工属于一个部门
    @ManyToOne(fetch=FetchType.LAZY)
    @JoinColumn(name="deptNo")
    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 getSal() {
        return sal;
    }

    public void setSal(Double salary) {
        this.sal = 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.sal = salary;
        this.hireDate = hireDate;
        this.dept = dept;
    }

    public Emp() {
        super();
    }

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

 

 

在hibernate.cfg.xml中管理 实体类

    <!--加载我们配置 注解类 -->
    <mapping class="cn.bdqn.bean.Dept" />
    <mapping class="cn.bdqn.bean.Emp" />