Hibernate复合主键作外键该怎么样配置

数据库建表如下：

drop database choose ;
create database choose ;
use choose;
--student
create table student(
    sId char(10) not null primary key,
 sName char(20) not null,
 sPwd char(20) not null
);

create unique index PK_student on student(sId);
--course
create table course(
    coId char(10) not null primary key,
 coName char(20) not null,
 credit float(53) not null
);

create unique index PK_course on course(coId);
--chooseCourse
create table chooseCourse(
 coId char(10) not null,
 sId char(10) not null,
 grade float(53),
 primary key(coId,sId),
 foreign key (coId) references course(coId),
 foreign key (sId) references student(sId)
);

insert into student values('0621','jj,'668668668');

insert into course values('0001','汇编原理','3.0');

insert into course values('0002','网页设计与制作','2.0');

insert into chooseCourse values('0001','0621',76.7);

insert into chooseCourse values('0002','0621',80.0);

 

 

Student.java

package vo;

import java.io.Serializable;
import java.util.Set;

import org.apache.commons.lang.builder.EqualsBuilder;
import org.apache.commons.lang.builder.HashCodeBuilder;

public class Student implements Serializable 
{
	private String sId;
	private String sName;
	private String sPwd;
	private Set chooseCourses;

	public Student() {
	}

	public String getsname() {
		return sName;
	}

	public void setsname(String name) {
		sName = name;
	}

	public String getspwd() {
		return sPwd;
	}

	public void setspwd(String pwd) {
		sPwd = pwd;
	}

	public String getsId() {
		return sId;
	}
	public void setsId(String id) {
		sId = id;
	}

	public Set getChooseCourses() {
		return chooseCourses;
	}

	public void setChooseCourses(Set chooseCourses) {
		this.chooseCourses = chooseCourses;
	}
	
	public boolean equals(Object obj) {
    	if (this == obj) {
			return true;
		}
		if (!(obj instanceof ChooseCourse)) {
			return false;
		}
		Student student = (Student) obj;
		return new EqualsBuilder().append(this.sId, student.getsId()).append(this.sName,
				student.getsname()).append(this.sPwd, student.getspwd()).append(this.chooseCourses, student.getChooseCourses()).isEquals();
	}

	public int hashCode() {
    	return new HashCodeBuilder().append(this.sId).append(
    			this.sName).append(this.sPwd).append(this.chooseCourses).toHashCode();
	}
}

 Student.hbm.xml

<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
<!-- 
    Mapping file autogenerated by MyEclipse Persistence Tools
-->
<hibernate-mapping>
    <class name="vo.Student" table="student" catalog="choose">
        <id name="sId" type="java.lang.String">
            <column name="sId" length="10" />
            <generator class="assigned" />
        </id>
        <property name="sname" type="java.lang.String">
            <column name="sName" length="20" not-null="true" />
        </property>
        <property name="spwd" type="java.lang.String">
            <column name="sPwd" length="20" not-null="true" />
        </property>
        <set name="chooseCourses" inverse="true">
            <key>
                <column name="sId" length="10" not-null="true" />
            </key>
            <one-to-many class="vo.ChooseCourse" />
        </set>
    </class>
</hibernate-mapping>

 Course.java

package vo;

import java.io.Serializable;
import java.util.Set;

public class Course implements Serializable 
{
	private String coId;
	private String coName;
	private double credit;
	private Set chooseCourse;

	public Course() {

	}

	public String getCoId() {
		return coId;
	}

	public void setCoId(String coId) {
		this.coId = coId;
	}

	public String getCoName() {
		return coName;
	}

	public void setCoName(String coName) {
		this.coName = coName;
	}

	public double getCredit() {
		return credit;
	}

	public void setCredit(double credit) {
		this.credit = credit;
	}

	public Set getChooseCourse() {
		return chooseCourse;
	}

	public void setChooseCourse(Set chooseCourse) {
		this.chooseCourse = chooseCourse;
	}


}

 

Course.hbm.xml

<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
<!-- 
    Mapping file autogenerated by MyEclipse Persistence Tools
-->
<hibernate-mapping>
    <class name="vo.Course" table="course" catalog="choose">
        <id name="coId" type="java.lang.String">
            <column name="coId" length="10" />
            <generator class="assigned" />
        </id>
        <property name="coName" type="java.lang.String">
            <column name="coName" length="20" not-null="true" />
        </property>
        <property name="credit" type="java.lang.Double">
            <column name="credit" precision="22" scale="0" not-null="true" />
        </property>
        <set name="chooseCourse" inverse="true">
            <key>
                <column name="coId" length="10" not-null="true" />
            </key>
            <one-to-many class="vo.ChooseCourse" />
        </set>
    </class>
</hibernate-mapping>

 ChooseCourse.java

package vo;

import java.io.Serializable;

public class ChooseCourse implements Serializable
{
	private ccPK ccpk;
	private double grade;
	public ChooseCourse()
	{
	}
	public double getGrade() {
		return grade;
	}
	public void setGrade(double grade) {
		this.grade = grade;
	}
	public ccPK getCcpk() {
		return ccpk;
	}
	public void setCcpk(ccPK ccpk) {
		this.ccpk = ccpk;
	}
}

 ChooseCourse.hbm.xml

<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
<!-- 
    Mapping file autogenerated by MyEclipse Persistence Tools
-->
<hibernate-mapping>
    <class name="vo.ChooseCourse" table="choosecourse" catalog="choose">
        <composite-id name="ccpk" class="vo.ccPK">
            <key-many-to-one name="course" class="vo.Course">
                <column name="coId" length="10" />
            </key-many-to-one>
            <key-many-to-one name="student" class="vo.Student">
                <column name="sId" length="10" />
            </key-many-to-one>
        </composite-id>
        <property name="grade" type="java.lang.Double">
            <column name="grade" precision="22" scale="0" />
        </property>
    </class>
</hibernate-mapping>

 最终测试类Test.java：

package test;

import java.util.Iterator;
import java.util.Set;

import org.hibernate.Session;
import org.hibernate.Transaction;

import vo.ChooseCourse;
import vo.Course;
import vo.Student;
import vo.ccPK;

public class Test
{
	public static void main(String[] args)
	{
		Session session = util.HibernateSessionFactory.getSession();
		Transaction tran = session.beginTransaction();
		Student stu = (Student)session.get(Student.class, "0621");		
		Set set = stu.getChooseCourses() ;
		Iterator ite = set.iterator();//这里出错了！是为何？是配置错误还是测试类有问题？
		while(ite.hasNext()){
			ChooseCourse ccc = (ChooseCourse)ite.next();
			System.out.println(ccc.getGrade());
		}
	}
}

 

最后测试类出问题了，请高手看一下，是我的配置错误还是测试类有问题？

谢谢！

 

评论

1 楼 66605127 2008-07-28  

楼主怎么解决的