java：Hibernate框架2（关联映射（多对一，一对多，一对多双向，一对一主键，一对一唯一外键，多对多双向））
hibernate.cfg.xml:
<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE hibernate-configuration PUBLIC "-//Hibernate/Hibernate Configuration DTD 3.0//EN" "http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd"> <hibernate-configuration> <session-factory> <!--驱动名称,URL,用户名,密码 --> <property name="connection.driver_class"> com.mysql.jdbc.Driver </property> <property name="connection.url"> jdbc:mysql://localhost:3306/test </property> <property name="connection.username">root</property> <property name="connection.password">root</property> <!--方言 --> <property name="hibernate.dialect"> org.hibernate.dialect.MySQL5Dialect </property> <!-- 输出SQL语句 --> <property name="show_sql">true</property> <!-- 格式化SQL语句 --> <property name="format_sql">true</property> <!-- 根据映射文件生产表: create:创建(不推荐:先删除原有表，重新创建表，原有数据丢失) update:创建+更新记录(推荐，会保存原有数据) --> <property name="hbm2ddl.auto">update</property> <mapping resource="cn/zzsxt/entity/Classinfo.hbm.xml" /> <mapping resource="cn/zzsxt/entity/Studentinfo.hbm.xml" /> <mapping resource="cn/zzsxt/entity2/Employee.hbm.xml" /> <mapping resource="cn/zzsxt/entity2/Dept.hbm.xml" /> <mapping resource="cn/zzsxt/entity3/Province.hbm.xml" /> <mapping resource="cn/zzsxt/entity3/City.hbm.xml" /> <mapping resource="cn/zzsxt/entity4/IdCard.hbm.xml" /> <mapping resource="cn/zzsxt/entity4/Person.hbm.xml" /> <mapping resource="cn/zzsxt/entity5/IdCard2.hbm.xml" /> <mapping resource="cn/zzsxt/entity5/Person2.hbm.xml" /> <mapping resource="cn/zzsxt/entity6/Emp.hbm.xml" /> <mapping resource="cn/zzsxt/entity6/Project.hbm.xml" /> </session-factory> </hibernate-configuration>
1.单向多对一：
Classinfo:
package cn.zzsxt.entity; import java.io.Serializable; public class Classinfo implements Serializable { private int classId; private String className; public int getClassId() { return classId; } public void setClassId(int classId) { this.classId = classId; } public String getClassName() { return className; } public void setClassName(String className) { this.className = className; } }
Classinfo.hbm.xml:
<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN" "http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd"> <hibernate-mapping package="cn.zzsxt.entity"> <class name="Classinfo"> <id name="classId"> <generator class="native"></generator> </id> <property name="className"></property> </class> </hibernate-mapping>
Studentinfo:
package cn.zzsxt.entity; import java.io.Serializable; public class Studentinfo implements Serializable { private int studentId; private String studentName; private int studentAge; private String studentAddress; //和一方关联的实体对象(多对一) private Classinfo classinfo; public Studentinfo() { super(); // TODO Auto-generated constructor stub } public Studentinfo(String studentName, int studentAge, String studentAddress) { super(); this.studentName = studentName; this.studentAge = studentAge; this.studentAddress = studentAddress; } public int getStudentId() { return studentId; } public void setStudentId(int studentId) { this.studentId = studentId; } public String getStudentName() { return studentName; } public void setStudentName(String studentName) { this.studentName = studentName; } public int getStudentAge() { return studentAge; } public void setStudentAge(int studentAge) { this.studentAge = studentAge; } public String getStudentAddress() { return studentAddress; } public void setStudentAddress(String studentAddress) { this.studentAddress = studentAddress; } public Classinfo getClassinfo() { return classinfo; } public void setClassinfo(Classinfo classinfo) { this.classinfo = classinfo; } }
Studentinfo.hbm.xml:
<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN" "http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd"> <hibernate-mapping package="cn.zzsxt.entity"> <class name="Studentinfo"> <id name="studentId"> <generator class="native"></generator> </id> <property name="studentName"></property> <property name="studentAge"></property> <property name="studentAddress"></property> <!-- 多对一 --> <many-to-one name="classinfo" class="Classinfo" column="classId" lazy="false"></many-to-one> </class> </hibernate-mapping>
TestManyToOneSave:
package cn.zzsxt.test; import org.hibernate.Session; import org.hibernate.Transaction; import cn.zzsxt.entity.Classinfo; import cn.zzsxt.entity.Studentinfo; import cn.zzsxt.utils.HibernateUtil; public class TestManyToOneSave { /** * 新建一个班级:Java01,添加两个学生zhangsan和lisi，并将这两个学生添加到Java01班级中 * @param args */ public static void main(String[] args) { Session session = HibernateUtil.getSession(); Transaction tx = session.beginTransaction(); //新建班级Java01 Classinfo classinfo = new Classinfo(); classinfo.setClassName("Java01"); //新建两个学生zhangsan和lisi Studentinfo stu1 = new Studentinfo("zhangsan",20,"郑州"); Studentinfo stu2 = new Studentinfo("lisi",22,"北京"); //维护班级和学生之间的关系：单向多对一(从多方维护关联关系)：为学生指定班级 stu1.setClassinfo(classinfo); stu2.setClassinfo(classinfo); //保存班级和学生 session.save(classinfo); session.save(stu1); session.save(stu2); tx.commit(); session.close(); } }
TestManyToOneSelect:
package cn.zzsxt.test; import org.hibernate.Session; import cn.zzsxt.entity.Classinfo; import cn.zzsxt.entity.Studentinfo; import cn.zzsxt.utils.HibernateUtil; public class TestManyToOneSelect { /** * 查询编号为1的学生信息及对应的班级信息 * @param args */ public static void main(String[] args) { Session session = HibernateUtil.getSession(); Studentinfo student = session.get(Studentinfo.class,1); System.out.println(student.getStudentName()+"---"+student.getStudentAge()); //获取学生对应的班级信息 Classinfo classinfo = student.getClassinfo(); System.out.println("班级名称:"+classinfo.getClassName()); session.close(); } }
2.单向一对多：
Dept：
package cn.zzsxt.entity2; import java.util.HashSet; import java.util.Set; public class Dept { private int deptId; private String deptName; //在一方添加一个包含多方的集合 private Set<Employee> emps = new HashSet<Employee>(); public int getDeptId() { return deptId; } public void setDeptId(int deptId) { this.deptId = deptId; } public String getDeptName() { return deptName; } public void setDeptName(String deptName) { this.deptName = deptName; } public Set<Employee> getEmps() { return emps; } public void setEmps(Set<Employee> emps) { this.emps = emps; } }
Dept.hbm.xml:
<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN" "http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd"> <hibernate-mapping package="cn.zzsxt.entity2"> <class name="Dept"> <id name="deptId"> <generator class="native"></generator> </id> <property name="deptName"></property> <!-- name="包含多方的集合名称" --> <set name="emps"> <!-- column="外键名称" --> <key column="deptId"></key> <!-- 一对多 class="集合中元素的类型(多方的类型)" --> <one-to-many class="Employee"/> </set> </class> </hibernate-mapping>
Employee:
package cn.zzsxt.entity2; public class Employee { private int empId; private String empName; public int getEmpId() { return empId; } public void setEmpId(int empId) { this.empId = empId; } public String getEmpName() { return empName; } public void setEmpName(String empName) { this.empName = empName; } }
Employee.hbm,xml:
<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN" "http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd"> <hibernate-mapping package="cn.zzsxt.entity2"> <class name="Employee"> <id name="empId"> <generator class="native"></generator> </id> <property name="empName"></property> </class> </hibernate-mapping>
TestOneToManySave:
package cn.zzsxt.test; import org.hibernate.Session; import org.hibernate.Transaction; import cn.zzsxt.entity2.Dept; import cn.zzsxt.entity2.Employee; import cn.zzsxt.utils.HibernateUtil; public class TestOneToManySave { /** * 添加一个部门：开发部 * 添加两个员工:小三和小四，并且将这两个员工分配到开发部 * @param args * 推荐从多方维护关系: * 1.生产的SQL语句数量少，执行效率较高。 * 2.可以避免因外键不能为NULL带来的异常。 */ public static void main(String[] args) { Session session = HibernateUtil.getSession(); Transaction tx = session.beginTransaction(); //创建开发部 Dept dept = new Dept(); dept.setDeptName("开发部2"); //创建两个员工 Employee emp1 = new Employee(); emp1.setEmpName("小三2"); Employee emp2 = new Employee(); emp2.setEmpName("小四2"); //单项一对多(只能在一方维护关联关系):为部门添加员工 dept.getEmps().add(emp1); dept.getEmps().add(emp2); //保存部门和员工 session.save(dept); session.save(emp1); session.save(emp2); tx.commit(); session.close(); } }
3.双向一对多,控制反转,级联：
City：
package cn.zzsxt.entity3; public class City { private int cityId; private String cityName; //多方添加一个和一方关联的实体对象 private Province province; public int getCityId() { return cityId; } public void setCityId(int cityId) { this.cityId = cityId; } public String getCityName() { return cityName; } public void setCityName(String cityName) { this.cityName = cityName; } public Province getProvince() { return province; } public void setProvince(Province province) { this.province = province; } }
City.hbm.xml:
<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN" "http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd"> <hibernate-mapping package="cn.zzsxt.entity3"> <class name="City"> <id name="cityId"> <generator class="native"></generator> </id> <property name="cityName"></property> <!-- many-to-one :多对一 cascade:级联(存在关联的数据表，一份随另外关联一方做相同的操作) delete:级联删除 save-update:级联新增或修改 all:所有操作都级联 none:不级联 --> <many-to-one name="province" class="Province" column="provinceId" cascade="save-update" ></many-to-one> </class> </hibernate-mapping>
Province:
package cn.zzsxt.entity3; import java.util.HashSet; import java.util.Set; public class Province { private int provinceId; private String provinceName; //一份添加一个包含多方的set集合 private Set<City> cities = new HashSet<City>(); public int getProvinceId() { return provinceId; } public void setProvinceId(int provinceId) { this.provinceId = provinceId; } public String getProvinceName() { return provinceName; } public void setProvinceName(String provinceName) { this.provinceName = provinceName; } public Set<City> getCities() { return cities; } public void setCities(Set<City> cities) { this.cities = cities; } }
Province.hbm.xml:
<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN" "http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd"> <hibernate-mapping package="cn.zzsxt.entity3"> <class name="Province"> <id name="provinceId"> <generator class="native"></generator> </id> <property name="provinceName"></property> <!-- name="包含多方的集合名称" cascade="save-update|delete|all|none" 级联 inverse="true|false" inverse代表关系维护的控制权是否反转,如果inverse值为true代表将关系维护的控制权交与对方 --> <set name="cities" cascade="all" inverse="true"> <!-- column="外键名称" --> <key column="provinceId"></key> <!-- 一对多 class="集合中元素的类型(多方的类型)" --> <one-to-many class="City"/> </set> </class> </hibernate-mapping>
TestOneToMany:
package cn.zzsxt.test; import org.hibernate.Session; import org.hibernate.Transaction; import cn.zzsxt.entity2.Dept; import cn.zzsxt.entity2.Employee; import cn.zzsxt.entity3.City; import cn.zzsxt.entity3.Province; import cn.zzsxt.utils.HibernateUtil; public class TestOneToMany { /** * 添加一个省份:河南省 * 添加一个城市:郑州市 * 将郑州市添加到河南省中 */ public static void main(String[] args) { Session session = HibernateUtil.getSession(); Transaction tx = session.beginTransaction(); //创建省份 Province province = new Province(); province.setProvinceName("河南省"); //创建城市 City city = new City(); city.setCityName("郑州市"); //从一份维护关系:为省份添加城市;从多方维护关系:为城市设置省份 city.setProvince(province); session.save(province); session.save(city); tx.commit(); session.close(); } }
TestInverse:
package cn.zzsxt.test; import org.hibernate.Session; import org.hibernate.Transaction; import cn.zzsxt.entity3.City; import cn.zzsxt.entity3.Province; import cn.zzsxt.utils.HibernateUtil; /** * inverse="true"：代表将关系维护的控制权交与对方(多方)进行维护，自身无法维护关联关系 * @author Think * */ public class TestInverse { public static void main(String[] args) { Session session = HibernateUtil.getSession(); Transaction tx = session.beginTransaction(); //创建一个河北省 Province province = new Province(); province.setProvinceName("山东省2"); //创建一个城市 City city = new City(); city.setCityName("济南2"); City city2 = new City(); city2.setCityName("菏泽2"); //为省份添加城市 province.getCities().add(city); province.getCities().add(city2); //通过省份级联城市 session.save(province); tx.commit(); session.close(); } }
TestCascade:
package cn.zzsxt.test; import org.hibernate.Session; import org.hibernate.Transaction; import cn.zzsxt.entity3.City; import cn.zzsxt.entity3.Province; import cn.zzsxt.utils.HibernateUtil; public class TestCascade { public static void main(String[] args) { Session session = HibernateUtil.getSession(); Transaction tx = session.beginTransaction(); //创建一个河北省 Province province = new Province(); province.setProvinceName("山东省"); //创建一个城市 City city = new City(); city.setCityName("济南"); City city2 = new City(); city2.setCityName("菏泽"); //为省份添加城市 province.getCities().add(city); province.getCities().add(city2); //通过省份级联城市 session.save(province); tx.commit(); session.close(); } }
TestCascade2:
package cn.zzsxt.test; import org.hibernate.Session; import org.hibernate.Transaction; import cn.zzsxt.entity3.City; import cn.zzsxt.entity3.Province; import cn.zzsxt.utils.HibernateUtil; public class TestCascade2 { public static void main(String[] args) { Session session = HibernateUtil.getSession(); Transaction tx = session.beginTransaction(); //创建一个河北省 Province province = new Province(); province.setProvinceName("河北省"); //创建一个城市 City city = new City(); city.setCityName("石家庄"); //为城市设置省份 city.setProvince(province); //使用级联新增城市的同时新增省份 session.save(city); tx.commit(); session.close(); } }
4.一对一主键关联：
IdCard：
package cn.zzsxt.entity4; public class IdCard { private int id; private String cardNo;//身份证号; private Person person;//关联的实体对象 public int getId() { return id; } public void setId(int id) { this.id = id; } public String getCardNo() { return cardNo; } public void setCardNo(String cardNo) { this.cardNo = cardNo; } public Person getPerson() { return person; } public void setPerson(Person person) { this.person = person; } }
IdCard.hbm.xml:
<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN" "http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd"> <hibernate-mapping package="cn.zzsxt.entity4"> <class name="IdCard"> <id name="id"> <!-- foreign:主键生产策略,该主键的值来源"外部"--> <generator class="foreign"> <!-- 利用property属性指定主键来源于person中的主键 --> <param name="property">person</param> </generator> </id> <property name="cardNo"></property> <!-- one-to-one:一对一 name属性:关联对象的名称 class属性:关联对象的类型 cascade:级联 constrained="true|false":可选属性. 代表是否是约束属性. 配置在这里,代表当前属性为约束属性,一定在这个属性对应的表中有 数据与本表数据对应. --> <one-to-one name="person" class="Person" constrained="true"></one-to-one> </class> </hibernate-mapping>
Person:
package cn.zzsxt.entity4; public class Person { private int id; private String name; private IdCard idCard;//关联的实体对象 public int getId() { return id; } public void setId(int id) { this.id = id; } public String getName() { return name; } public void setName(String name) { this.name = name; } public IdCard getIdCard() { return idCard; } public void setIdCard(IdCard idCard) { this.idCard = idCard; } }
Person.hbm.xml:
<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN" "http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd"> <hibernate-mapping package="cn.zzsxt.entity4"> <class name="Person"> <id name="id"> <generator class="native"></generator> </id> <property name="name"></property> <!-- one-to-one:一对一 name属性:关联对象的名称 class属性:关联对象的类型 cascade:级联 constrained="true|false":可选属性. 代表是否是约束属性. 配置在这里,代表当前属性为约束属性,一定在这个属性对应的表中有 数据与本表数据对应. --> <one-to-one name="idCard" class="IdCard" cascade="save-update"></one-to-one> </class> </hibernate-mapping>
TestOneToOne：
package cn.zzsxt.test2; import org.hibernate.Session; import org.hibernate.Transaction; import cn.zzsxt.entity4.IdCard; import cn.zzsxt.entity4.Person; import cn.zzsxt.utils.HibernateUtil; public class TestOneToOne { public static void main(String[] args) { Session session =HibernateUtil.getSession(); Transaction tx = session.beginTransaction(); Person person = new Person(); person.setName("zhangsan"); IdCard idCard = new IdCard(); idCard.setCardNo("412722199001011234"); //为人设置身份证 person.setIdCard(idCard); //为身份证指定人 idCard.setPerson(person); //通过级联添加人和身份证 session.save(person); tx.commit(); session.close(); } }
5.一对唯一外键关联：
IdCard2：
package cn.zzsxt.entity5; public class IdCard2 { private int id; private String cardNo;//身份证号; private Person2 person2;//关联的实体对象 public int getId() { return id; } public void setId(int id) { this.id = id; } public String getCardNo() { return cardNo; } public void setCardNo(String cardNo) { this.cardNo = cardNo; } public Person2 getPerson2() { return person2; } public void setPerson2(Person2 person2) { this.person2 = person2; } }
Idcard2.hbm.xml:
<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN" "http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd"> <hibernate-mapping package="cn.zzsxt.entity5"> <class name="IdCard2"> <id name="id"> <generator class="native"></generator> </id> <property name="cardNo"></property> <!-- 多对一 --> <many-to-one name="person2" class="Person2" column="pid" unique="true"></many-to-one> </class> </hibernate-mapping>
Person2:
package cn.zzsxt.entity5; public class Person2 { private int id; private String name; private IdCard2 idCard2;//关联的实体对象 public int getId() { return id; } public void setId(int id) { this.id = id; } public String getName() { return name; } public void setName(String name) { this.name = name; } public IdCard2 getIdCard2() { return idCard2; } public void setIdCard2(IdCard2 idCard2) { this.idCard2 = idCard2; } }
Person2.hbm.xml:
<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN" "http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd"> <hibernate-mapping package="cn.zzsxt.entity5"> <class name="Person2"> <id name="id"> <generator class="native"></generator> </id> <property name="name"></property> <!-- one-to-one:一对一 name属性:关联对象的名称 class属性:关联对象的类型 cascade:级联 constrained="true|false":可选属性. 代表是否是约束属性. 配置在这里,代表当前属性为约束属性,一定在这个属性对应的表中有 数据与本表数据对应. --> <one-to-one name="idCard2" class="IdCard2" cascade="save-update"></one-to-one> </class> </hibernate-mapping>
TestOneToOne2:
package cn.zzsxt.test2; import org.hibernate.Session; import org.hibernate.Transaction; import cn.zzsxt.entity5.IdCard2; import cn.zzsxt.entity5.Person2; import cn.zzsxt.utils.HibernateUtil; public class TestOneToOne2 { public static void main(String[] args) { Session session =HibernateUtil.getSession(); Transaction tx = session.beginTransaction(); Person2 person = new Person2(); person.setName("zhangsan"); IdCard2 idCard = new IdCard2(); idCard.setCardNo("412722199001011234"); //为人设置身份证 person.setIdCard2(idCard); //为身份证指定人 idCard.setPerson2(person); //通过级联添加人和身份证 session.save(person); tx.commit(); session.close(); } }
6.多对多双向关联：
Emp：
package cn.zzsxt.entity6; import java.util.HashSet; import java.util.Set; public class Emp { private int empId; private String empName; private Set<Project> projects = new HashSet<Project>(); public int getEmpId() { return empId; } public void setEmpId(int empId) { this.empId = empId; } public String getEmpName() { return empName; } public void setEmpName(String empName) { this.empName = empName; } public Set<Project> getProjects() { return projects; } public void setProjects(Set<Project> projects) { this.projects = projects; } }
Emp.hbm.xml:
<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN" "http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd"> <hibernate-mapping package="cn.zzsxt.entity6"> <class name="Emp" table="tbl_emp"> <id name="empId"> <generator class="native"></generator> </id> <property name="empName"></property> <!-- table="中间表的表名" --> <set name="projects" table="tbl_emp_project" cascade="all"> <!-- column:中间表中与Emp对应的外键名称 --> <key column="empId"></key> <!-- many-to-many:多对多 class="集合中的元素类型" column="中间表中与Project对应的外键名称" --> <many-to-many class="Project" column="projectId"></many-to-many> </set> </class> </hibernate-mapping>
project:
package cn.zzsxt.entity6; import java.util.HashSet; import java.util.Set; public class Project { private int projectId; private String projectName; private Set<Emp> emps = new HashSet<Emp>(); public int getProjectId() { return projectId; } public void setProjectId(int projectId) { this.projectId = projectId; } public String getProjectName() { return projectName; } public void setProjectName(String projectName) { this.projectName = projectName; } public Set<Emp> getEmps() { return emps; } public void setEmps(Set<Emp> emps) { this.emps = emps; } }
Project.hbm.xml:
<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN" "http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd"> <hibernate-mapping package="cn.zzsxt.entity6"> <class name="Project" table="tbl_project"> <id name="projectId"> <generator class="native"></generator> </id> <property name="projectName"></property> <!-- table="中间表的表名" --> <set name="emps" table="tbl_emp_project" inverse="true"> <!-- column:中间表中与Project对应的外键名称 --> <key column="projectId"></key> <!-- many-to-many:多对多 class="集合中的元素类型" column="中间表中与Emp对应的外键名称" --> <many-to-many class="Emp" column="empId"></many-to-many> </set> </class> </hibernate-mapping>
TestManyToMany:
package cn.zzsxt.test2; import org.hibernate.Session; import org.hibernate.Transaction; import cn.zzsxt.entity6.Emp; import cn.zzsxt.entity6.Project; import cn.zzsxt.utils.HibernateUtil; /** * * 添加两个员工:zhangsan和lisi * 添加两个项目:OA项目和CRM项目 * 将zhangsan和lisi分配到OA项目组 * 将lisi分配到CRM项目组 * @author Think * */ public class TestManyToMany { public static void main(String[] args) { Session session =HibernateUtil.getSession(); Transaction tx = session.beginTransaction(); //创建两个员工 Emp emp1 = new Emp(); emp1.setEmpName("张三"); Emp emp2 = new Emp(); emp2.setEmpName("李四"); //创建两个项目 Project project1 = new Project(); project1.setProjectName("OA项目"); Project project2 = new Project(); project2.setProjectName("CRM项目"); //关系维护的控制权在emp方,为员工添加项目 emp1.getProjects().add(project1);//为张三分配OA项目 emp2.getProjects().add(project1);//为李四分配OA项目 emp2.getProjects().add(project2);//为李四分配CRM项目 //保存员工和项目(级联) session.save(emp1); session.save(emp2); tx.commit(); session.close(); } }
