hibernate单表，一对多，多对多配置文件详解

小灰灰 2022-06-09 10:37 164阅读 0赞

**一、单表配置方式（使用配置关系映射文件去操作单表的CRUD操作）**

1.新建Course.java

public class Course {
    	
    	private Integer id;  //课程id
    	private String name; // 课程名称
    	
    
    	public Course() {
    	}
    
    	public Course(Integer id, String name) {
    		this.id = id;
    		this.name = name;
    	}
    
    	public Integer getId() {
    		return id;
    	}
    
    	public void setId(Integer id) {
    		this.id = id;
    	}
    
    	public String getName() {
    		return name;
    	}
    
    	public void setName(String name) {
    		this.name = name;
    	}
    
    	public String toString() {
    		return "Course [id=" + id + ", name=" + name + "]";
    	}
    
    }

2.新建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">
    <hibernate-mapping package="com.iflytek.model">
    	<class name="Course">
    	    
    		<id name="id" type="java.lang.Integer">
    			<generator class="increment">
    				<param name="increment">course_inc</param>
    			</generator>
    		</id>
    		
    		
    		<property name="name" type="java.lang.String">
    			<column name="name" length="64" />
    		</property>
    	</class>
    </hibernate-mapping>

3.测试类TestCourse.java

public class TestCourse {
    	private SessionFactory sessionFactory;
    	private Session session;
    	private Transaction transaction;
    	
    	@Before
    	public void init(){
    		//创建配置对象，加载配置文件 hibernate.cfg.xml
    		Configuration configuration = new Configuration().configure();
    		//创建会话连接工厂
    		sessionFactory = configuration.buildSessionFactory();
    		//打开会话
    		session = sessionFactory.openSession();
    		//开启事务
    		transaction = session.beginTransaction();
    	}
    	
    
    	@After
    	public void destory(){
    		//提交事务
    		transaction.commit();
    		//关闭会话
    		session.close();
    		//关闭工厂会话连接
    		sessionFactory.close();
    		
    	}
    
    	/**
    	 * 新增课程信息
    	 */
    	@Test
    	public void testSaveCourse() {
    		Course cou = new Course();
    		cou.setName("java");
    		session.save(cou);
    		
    		Course cou2 = new Course(2, "python");
    		session.save(cou2);
    	}
    
    	/**
    	 * 更新课程信息
    	 */
    	@Test
    	public void testUpdateStu() {
    		// 获取一个课程对象
    		Course cou = (Course) session.get(Course.class, 1);
    		cou.setName("c++");
    		session.save(cou);
    	}
    
    	/**
    	 * 删除课程信息
    	 */
    	@Test
    	public void testDeleteStu() {
    		Course cou = (Course) session.get(Course.class, 2);
    		session.delete(cou);
    	}
    
    	/**
    	 * 查询课程信息
    	 */
    	@Test
    	public void testGetStu() {
    		Course cou = (Course) session.get(Course.class, 1);
    		System.out.println(cou);
    
    	}
    
    
    
    }

二、一对多配置方式（一个学生对应多个选课记录）

1.新建Course3.java

public class Course3 {
    	
    	private Integer id;  //课程id
    	private String name; // 课程名称
    	
    	private Student3 stu;
    
    	public Course3() {
    	}
    
    	public Course3(Integer id, String name) {
    		this.id = id;
    		this.name = name;
    	}
    
    	public Integer getId() {
    		return id;
    	}
    
    	public void setId(Integer id) {
    		this.id = id;
    	}
    
    	public String getName() {
    		return name;
    	}
    
    	public void setName(String name) {
    		this.name = name;
    	}
    
    	public Student3 getStu() {
    		return stu;
    	}
    
    	public void setStu(Student3 stu) {
    		this.stu = stu;
    	}
    
    	public String toString() {
    		return "Course [id=" + id + ", name=" + name + "]";
    	}
    
    }

2.新建Course3.hbm.xml

3.新建Student3.java

public class Student3 {
    
    	private Integer sid; // 学生id
    	private String name; // 学生姓名
    	private String gender; // 学生姓名
    	private Date birthday; // 学生出生日期
    	
    	private Set<Course3> cous = new HashSet<Course3>();
    
    	public Student3() {
    
    	}
    
    	
    
    	public Integer getSid() {
    		return sid;
    	}
    
    
    
    	public void setSid(Integer sid) {
    		this.sid = sid;
    	}
    
    
    
    	public String getName() {
    		return name;
    	}
    
    
    
    	public void setName(String name) {
    		this.name = name;
    	}
    
    
    
    	public String getGender() {
    		return gender;
    	}
    
    
    
    	public void setGender(String gender) {
    		this.gender = gender;
    	}
    
    
    
    	public Date getBirthday() {
    		return birthday;
    	}
    
    
    
    	public void setBirthday(Date birthday) {
    		this.birthday = birthday;
    	}
    
    
    
    	public Set<Course3> getCous() {
    		return cous;
    	}
    
    
    
    	public void setCous(Set<Course3> cous) {
    		this.cous = cous;
    	}
    
    
    
    	public String toString() {
    		return "Student [sid=" + sid + ", name=" + name + ", gender=" + gender
    				+ ", birthday=" + birthday + "]";
    	}
    	
    }

4.新建Student3.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">
    <hibernate-mapping package="com.iflytek.model3">
    	<class name="Student3">
    		<id name="sid" type="integer">
    			<generator class="increment">
    				<param name="increment">stu_inc</param>
    			</generator>
    		</id>
    		<property name="name" type="string">
    			<column name="name" length="64" />
    		</property>
    
    		<property name="gender" type="string">
    			<column name="gender"></column>
    		</property>
    		<property name="birthday" type="timestamp">
    			<column name="birthday"></column>
    		</property>
    		
    		 <set name="cous" cascade="save-update,delete"> <key column="sid"></key> <one-to-many class="Course3" /> </set>
    	</class>
    </hibernate-mapping>

5.测试类TestStudent3.java

public class TestStudent3 {
    	private SessionFactory sessionFactory;
    	private Session session;
    	private Transaction transaction;
    	
    	@Before
    	public void init(){
    		//创建配置对象，加载配置文件 hibernate.cfg.xml
    		Configuration configuration = new Configuration().configure();
    		//创建会话连接工厂
    		sessionFactory = configuration.buildSessionFactory();
    		//打开会话
    		session = sessionFactory.openSession();
    		//开启事务
    		transaction = session.beginTransaction();
    	}
    	
    
    	@After
    	public void destory(){
    		//提交事务
    		transaction.commit();
    		//关闭会话
    		session.close();
    		//关闭工厂会话连接
    		sessionFactory.close();
    		
    	}
    
    	/**
    	 * 新增学生信息
    	 */
    	@Test
    	public void testSaveStudent() {
    		Student3 stu = new Student3();
    		stu.setName("张三丰");
    		stu.setGender("男");
    		stu.setBirthday(new Date());
    		
    		Course3 cou1 = new Course3();
    		cou1.setName("java");
    		
    		Course3 cou2 = new Course3();
    		cou2.setName("c");
    		
    		stu.getCous().add(cou1);
    		stu.getCous().add(cou2);
    		
    		
    		session.save(stu);
    	
    	}
    
    	/**
    	 * 更新学生信息
    	 */
    	@Test
    	public void testUpdateStu() {
    		// 获取一个学生对象
    		Student3 stu = (Student3) session.get(Student3.class, 1);
    		stu.setName("张峰");
    		session.save(stu);
    	}
    
    	/**
    	 * 删除学生信息，同时删除课程表course3对应的数据
    	 */
    	@Test
    	public void testDeleteStu() {
    		Student3 stu = (Student3) session.get(Student3.class, 1);
    		session.delete(stu);
    	}
    
    	/**
    	 * 查询学生信息
    	 */
    	@Test
    	public void testGetStu() {
    		Student3 stu = (Student3) session.get(Student3.class, 1);
    		System.out.println(stu);
    	}
    }

三、多对多（学生与课程多对多关系）

1.新建Course4.java

public class Course4 {
    	
    	private Integer id;  //课程id
    	private String name; // 课程名称
    	
    	private Set<Student4> students=new HashSet<Student4>();
    
    	public Course4() {
    	}
    
    	public Course4(Integer id, String name) {
    		this.id = id;
    		this.name = name;
    	}
    
    	public Integer getId() {
    		return id;
    	}
    
    	public void setId(Integer id) {
    		this.id = id;
    	}
    
    	public String getName() {
    		return name;
    	}
    
    	public void setName(String name) {
    		this.name = name;
    	}
    
    	public Set<Student4> getStudents() {
    		return students;
    	}
    
    	public void setStudents(Set<Student4> students) {
    		this.students = students;
    	}
    
    	public String toString() {
    		return "Course [id=" + id + ", name=" + name + "]";
    	}
    
    }

2.新建Course4.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">
    <hibernate-mapping package="com.iflytek.model4">
    	<class name="Course4">
    		
    		<id name="id" column="id" type="integer">
    			<generator class="native"></generator>
    		</id>
    		<property name="name" type="java.lang.String">
    			<column name="name" length="64" />
    		</property>
    		 <set name="students" table="student_course" cascade="save-update,delete"> <key column="id"></key> <many-to-many class="Student4" column="sid"></many-to-many> </set>
    	</class>
    </hibernate-mapping>

3.新建Student4.java

public class Student4 {
    
    	private Integer sid; // 学生id
    	private String name; // 学生姓名
    	private String gender; // 学生性别
    	private Date birthday; // 学生出生日期
    	
    	private Set<Course4> courses = new HashSet<Course4>();
    
    	public Student4() {
    
    	}
    
    	public Integer getSid() {
    		return sid;
    	}
    
    
    
    	public void setSid(Integer sid) {
    		this.sid = sid;
    	}
    
    
    
    	public String getName() {
    		return name;
    	}
    
    
    
    	public void setName(String name) {
    		this.name = name;
    	}
    
    
    
    	public String getGender() {
    		return gender;
    	}
    
    
    
    	public void setGender(String gender) {
    		this.gender = gender;
    	}
    
    
    
    	public Date getBirthday() {
    		return birthday;
    	}
    
    
    
    	public void setBirthday(Date birthday) {
    		this.birthday = birthday;
    	}
    
    
    
    	public Set<Course4> getCourses() {
    		return courses;
    	}
    
    
    
    	public void setCourses(Set<Course4> courses) {
    		this.courses = courses;
    	}
    
    
    
    	public String toString() {
    		return "Student4 [sid=" + sid + ", name=" + name + ", gender=" + gender
    				+ ", birthday=" + birthday + "]";
    	}
    	
    }

4.新建Student4.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">
    <hibernate-mapping package="com.iflytek.model4">
    	<class name="Student4">
    		
    		<id name="sid" column="sid" type="integer">
    			<generator class="native"></generator>
    		</id>
    		<property name="name" type="string">
    			<column name="name" length="64" />
    		</property>
    
    		<property name="gender" type="string">
    			<column name="gender"></column>
    		</property>
    		<property name="birthday" type="timestamp">
    			<column name="birthday"></column>
    		</property>
    
    		 <set name="courses" table="student_course" cascade="save-update,delete"> <key column="sid"></key> <many-to-many class="Course4" column="id"></many-to-many> </set>
    
    	</class>
    </hibernate-mapping>

5.测试类 TestManyToMany.java

public class TestManyToMany {
    	private SessionFactory sessionFactory;
    	private Session session;
    	private Transaction transaction;
    	
    	@Before
    	public void init(){
    		//创建配置对象，加载配置文件 hibernate.cfg.xml
    		Configuration configuration = new Configuration().configure();
    		//创建会话连接工厂
    		sessionFactory = configuration.buildSessionFactory();
    		//打开会话
    		session = sessionFactory.openSession();
    		//开启事务
    		transaction = session.beginTransaction();
    	}
    	
    
    	@After
    	public void destory(){
    		//提交事务
    		transaction.commit();
    		//关闭会话
    		session.close();
    		//关闭工厂会话连接
    		sessionFactory.close();
    		
    	}
    
    	/**
    	 * 新增学生 和课程信息
    	 */
    	@Test
    	public void saveStudent() {
    		Student4 stu = new Student4();
    		stu.setName("张三丰");
    		stu.setGender("男");
    		stu.setBirthday(new Date());
    		
    		Student4 stu2 = new Student4();
    		stu2.setName("张亮");
    		stu2.setGender("男");
    		stu2.setBirthday(new Date());
    		
    		Course4 c1=new Course4();  
    		c1.setName("English");  
    		Course4 c2=new Course4();  
    		c2.setName("science");  
    		
    		stu.getCourses().add(c1);  
    		stu.getCourses().add(c2);  
    		
    		stu2.getCourses().add(c1);  
    		stu2.getCourses().add(c2);
    		
    		
    		session.save(stu); 
    		session.save(stu2); 
    	}
    
    	/**
    	 * 更新学生信息
    	 */
    	@Test
    	public void testUpdateStu() {
    		// 获取一个学生对象
    		Student4 stu = (Student4) session.get(Student4.class, 1);
    		stu.setName("张峰");
    		session.save(stu);
    	}
    
    	/**
    	 * 删除学生信息
    	 */
    	@Test
    	public void testDeleteStu() {
    		Student4 stu = (Student4) session.get(Student4.class, 1);
    		session.delete(stu);
    	}
    
    	/**
    	 * 查询学生信息
    	 */
    	@Test
    	public void testGetStu() {
    		Student4 stu = (Student4) session.get(Student4.class, 1);
    		System.out.println(stu);
    	}
    }