Hibernate 一对多注解实例源码介绍



Hibernate 一对多注解实例源码介绍。

student：

 

  1. /**
  2. *
  3. */
  4. package com.wonders.task.sample.bo;
  6. import javax.persistence.CascadeType;
  7. import javax.persistence.Column;
  8. import javax.persistence.Entity;
  9. import javax.persistence.GeneratedValue;
  10. import javax.persistence.Id;
  11. import javax.persistence.JoinColumn;
  12. import javax.persistence.ManyToOne;
  13. import javax.persistence.Table;
  15. import org.hibernate.annotations.GenericGenerator;
  17. /**
  18. * @ClassName: Student
  19. * @Description: TODO(这里用一句话描述这个类的作用)
  20. * @author zhoushun
  21. * @date 2014年2月27日 上午11:48:30
  22. *
  23. */
  25. @Entity
  26. @Table(name=”Z_STUDENT”)
  27. public class Student {
  28.     private String id;
  29.     private String name;
  30.     private Clazz clazz;
  33.     @Id
  34.     @GeneratedValue(generator=”system-uuid”)
  35.     @GenericGenerator(name=”system-uuid”, strategy = “uuid”)
  36.     @Column(name = “ID”)
  37.     public String getId() {
  38.         return id;
  39.     }
  40.     public void setId(String id) {
  41.         this.id = id;
  42.     }
  44.     @Column(name = “NAME”, length = 500)
  45.     public String getName() {
  46.         return name;
  47.     }
  48.     public void setName(String name) {
  49.         this.name = name;
  50.     }
  52.     @ManyToOne(cascade={CascadeType.ALL})
  53.     @JoinColumn(name=”class_id”)     //student类中对应外键的属性：classid
  54.     public Clazz getClazz() {
  55.         return clazz;
  56.     }
  57.     public void setClazz(Clazz clazz) {
  58.         this.clazz = clazz;
  59.     }
  62. }
/**
 * 
 */
package com.wonders.task.sample.bo;

import javax.persistence.CascadeType;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.ManyToOne;
import javax.persistence.Table;

import org.hibernate.annotations.GenericGenerator;

/** 
 * @ClassName: Student 
 * @Description: TODO(这里用一句话描述这个类的作用) 
 * @author zhoushun 
 * @date 2014年2月27日 上午11:48:30 
 *  
 */

@Entity 
@Table(name="Z_STUDENT") 
public class Student {
	private String id;
	private String name;
	private Clazz clazz;

	@Id
	@GeneratedValue(generator="system-uuid")
	@GenericGenerator(name="system-uuid", strategy = "uuid")
	@Column(name = "ID")
	public String getId() {
		return id;
	}
	public void setId(String id) {
		this.id = id;
	}

	@Column(name = "NAME", length = 500)
	public String getName() {
		return name;
	}
	public void setName(String name) {
		this.name = name;
	}

	@ManyToOne(cascade={CascadeType.ALL})         
  	@JoinColumn(name="class_id")     //student类中对应外键的属性：classid 
	public Clazz getClazz() {
		return clazz;
	}
	public void setClazz(Clazz clazz) {
		this.clazz = clazz;
	}

}

classes:

 

 

  1. /**
  2. *
  3. */
  4. package com.wonders.task.sample.bo;
  6. import java.util.Set;
  8. import javax.persistence.CascadeType;
  9. import javax.persistence.Column;
  10. import javax.persistence.Entity;
  11. import javax.persistence.GeneratedValue;
  12. import javax.persistence.Id;
  13. import javax.persistence.OneToMany;
  14. import javax.persistence.Table;
  16. import org.hibernate.annotations.GenericGenerator;
  19. /**
  20. * @ClassName: Clazz
  21. * @Description: TODO(这里用一句话描述这个类的作用)
  22. * @author zhoushun
  23. * @date 2014年2月27日 上午11:48:47
  24. *
  25. */
  26. @Entity
  27. @Table(name=”Z_CLASS”)
  28. public class Clazz implements java.io.Serializable{
  29.     /**
  30.      *
  31.      */
  32.     private static final long serialVersionUID = -6224738252966513441L;
  33.     private String id;
  34.     private String name;
  35.     private Set<Student> set;
  37.     @Id
  38.     @GeneratedValue(generator=”system-uuid”)
  39.     @GenericGenerator(name=”system-uuid”, strategy = “uuid”)
  40.     @Column(name = “ID”)
  41.     public String getId() {
  42.         return id;
  43.     }
  44.     public void setId(String id) {
  45.         this.id = id;
  46.     }
  48.     @Column(name = “NAME”, length = 500)
  49.     public String getName() {
  50.         return name;
  51.     }
  52.     public void setName(String name) {
  53.         this.name = name;
  54.     }
  56.     @OneToMany(cascade=CascadeType.ALL,mappedBy=”clazz”)
  57.        //@OneToMany(cascade=CascadeType.ALL,mappedBy=”clazz”,fetch=FetchType.EAGER) 关闭延迟加载。
  58.     public Set<Student> getSet() {
  59.         return set;
  60.     }
  61.     public void setSet(Set<Student> set) {
  62.         this.set = set;
  63.     }
  67. }
/**
 * 
 */
package com.wonders.task.sample.bo;

import java.util.Set;

import javax.persistence.CascadeType;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.OneToMany;
import javax.persistence.Table;

import org.hibernate.annotations.GenericGenerator;

/** 
 * @ClassName: Clazz 
 * @Description: TODO(这里用一句话描述这个类的作用) 
 * @author zhoushun 
 * @date 2014年2月27日 上午11:48:47 
 *  
 */
@Entity 
@Table(name="Z_CLASS") 
public class Clazz implements java.io.Serializable{
	/**
	 * 
	 */
	private static final long serialVersionUID = -6224738252966513441L;
	private String id;
	private String name;
	private Set<Student> set;

	@Id
	@GeneratedValue(generator="system-uuid")
	@GenericGenerator(name="system-uuid", strategy = "uuid")
	@Column(name = "ID")
	public String getId() {
		return id;
	}
	public void setId(String id) {
		this.id = id;
	}

	@Column(name = "NAME", length = 500)
	public String getName() {
		return name;
	}
	public void setName(String name) {
		this.name = name;
	}

	@OneToMany(cascade=CascadeType.ALL,mappedBy="clazz") 
       //@OneToMany(cascade=CascadeType.ALL,mappedBy="clazz",fetch=FetchType.EAGER) 关闭延迟加载。        
	public Set<Student> getSet() {
		return set;
	}
	public void setSet(Set<Student> set) {
		this.set = set;
	}

}

 

 

main:

  1. /**
  2. *
  3. */
  4. package com.wonders.task.sample.main;
  6. import java.util.HashSet;
  7. import java.util.Set;
  9. import javax.annotation.Resource;
  11. import org.hibernate.Hibernate;
  12. import org.hibernate.Session;
  13. import org.springframework.context.ApplicationContext;
  14. import org.springframework.context.annotation.Scope;
  15. import org.springframework.context.support.ClassPathXmlApplicationContext;
  16. import org.springframework.orm.hibernate3.HibernateTemplate;
  17. import org.springframework.stereotype.Service;
  18. import org.springframework.transaction.annotation.Propagation;
  19. import org.springframework.transaction.annotation.Transactional;
  21. import com.wonders.schedule.util.SpringBeanUtil;
  22. import com.wonders.task.sample.ITaskService;
  23. import com.wonders.task.sample.bo.Clazz;
  24. import com.wonders.task.sample.bo.Student;
  26. /**
  27. * @ClassName: TestMain
  28. * @Description: TODO(这里用一句话描述这个类的作用)
  29. * @author zhoushun
  30. * @date 2014年2月27日 下午12:18:44
  31. *
  32. */
  34. @Transactional(propagation = Propagation.REQUIRED, rollbackFor = Exception.class)
  35. /* 功能模块入口点，beanid即数据库配置中的name */
  36. @Service(“testMain”)
  37. @Scope(“prototype”)
  38. public class TestMain {
  39.     private HibernateTemplate hibernateTemplate;
  41.     public HibernateTemplate getHibernateTemplate() {
  42.         return hibernateTemplate;
  43.     }
  45.     //注入hibernateTemplate
  46.     @Resource(name=”hibernateTemplate”)
  47.     public void setHibernateTemplate(HibernateTemplate hibernateTemplate) {
  48.         this.hibernateTemplate = hibernateTemplate;
  49.     }
  51.     public void test(){
  52.         Session session = this.getHibernateTemplate().getSessionFactory().getCurrentSession();
  53.         Clazz c2 = (Clazz) session.get(Clazz.class, “8a81a97c4471c661014471c669360002″);
  54.         //Clazz c2 = (Clazz) main.getHibernateTemplate().get(Clazz.class, “8a81a97c4471c661014471c669360002″);
  55.         Hibernate.initialize(c2.getSet());
  57.         System.out.println(“11111111111111111111111″);
  58.         //session.close();
  59.         Set<Student> sss =  c2.getSet();
  60.         System.out.println(“22222222222222222″);
  61.         for(Student s: sss){
  63.             System.out.println(s.getName());
  64.         }
  65.     }
  67.     public static void main(String[] args){
  68.         ApplicationContext applicationContext = null;
  69.         String[] fileUrl = new String[]{“classpath*:applicationContext*.xml”};
  70.         applicationContext = new ClassPathXmlApplicationContext(fileUrl);
  72.         Student s1 = new Student();
  73.         Student s2 = new Student();
  74.         Clazz c1 = new Clazz();
  75.         c1.setName(“1班”);
  76.         s1.setName(“z1″);
  77.         s1.setClazz(c1);
  78.         s2.setName(“z2″);
  79.         s2.setClazz(c1);
  80.         Set<Student> set = new HashSet<Student>();
  81.         set.add(s1);set.add(s2);
  82.         c1.setSet(set);
  83.         TestMain main = (TestMain)SpringBeanUtil.getBean(“testMain”);
  84.         //main.getHibernateTemplate().save(c1);
  86. //      Session session = main.getHibernateTemplate().getSessionFactory().openSession();
  87. //      Clazz c2 = (Clazz) session.get(Clazz.class, “8a81a97c4471c661014471c669360002″);
  88. //      //Clazz c2 = (Clazz) main.getHibernateTemplate().get(Clazz.class, “8a81a97c4471c661014471c669360002″);
  89. //      Hibernate.initialize(c2.getSet());
  90. //
  91. //      System.out.println(“11111111111111111111111″);
  92. //      session.close();
  93. //      Set<Student> sss =  c2.getSet();
  94. //      System.out.println(“22222222222222222″);
  95. //      for(Student s: sss){
  96. //
  97. //          System.out.println(s.getName());
  98. //      }
  99.         main.test();
  100.         //main.getHibernateTemplate().delete(c2);
  101.     }
  102. }
/**
 * 
 */
package com.wonders.task.sample.main;

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

import javax.annotation.Resource;

import org.hibernate.Hibernate;
import org.hibernate.Session;
import org.springframework.context.ApplicationContext;
import org.springframework.context.annotation.Scope;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import org.springframework.orm.hibernate3.HibernateTemplate;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Propagation;
import org.springframework.transaction.annotation.Transactional;

import com.wonders.schedule.util.SpringBeanUtil;
import com.wonders.task.sample.ITaskService;
import com.wonders.task.sample.bo.Clazz;
import com.wonders.task.sample.bo.Student;

/** 
 * @ClassName: TestMain 
 * @Description: TODO(这里用一句话描述这个类的作用) 
 * @author zhoushun 
 * @date 2014年2月27日 下午12:18:44 
 *  
 */

@Transactional(propagation = Propagation.REQUIRED, rollbackFor = Exception.class)
/* 功能模块入口点，beanid即数据库配置中的name */
@Service("testMain")
@Scope("prototype")
public class TestMain {
	private HibernateTemplate hibernateTemplate;

	public HibernateTemplate getHibernateTemplate() {
		return hibernateTemplate;
	}

	//注入hibernateTemplate
	@Resource(name="hibernateTemplate")
	public void setHibernateTemplate(HibernateTemplate hibernateTemplate) {
		this.hibernateTemplate = hibernateTemplate;
	}

	public void test(){
		Session session = this.getHibernateTemplate().getSessionFactory().getCurrentSession();
		Clazz c2 = (Clazz) session.get(Clazz.class, "8a81a97c4471c661014471c669360002");
		//Clazz c2 = (Clazz) main.getHibernateTemplate().get(Clazz.class, "8a81a97c4471c661014471c669360002");
		Hibernate.initialize(c2.getSet());

		System.out.println("11111111111111111111111");
		//session.close();
		Set<Student> sss =  c2.getSet();
		System.out.println("22222222222222222");
		for(Student s: sss){

			System.out.println(s.getName());
		}
	}

	public static void main(String[] args){
		ApplicationContext applicationContext = null;  
		String[] fileUrl = new String[]{"classpath*:applicationContext*.xml"};  
		applicationContext = new ClassPathXmlApplicationContext(fileUrl);  

		Student s1 = new Student();
		Student s2 = new Student();
		Clazz c1 = new Clazz();
		c1.setName("1班");
		s1.setName("z1");
		s1.setClazz(c1);
		s2.setName("z2");
		s2.setClazz(c1);
		Set<Student> set = new HashSet<Student>();
		set.add(s1);set.add(s2);
		c1.setSet(set);
		TestMain main = (TestMain)SpringBeanUtil.getBean("testMain");
		//main.getHibernateTemplate().save(c1);

//		Session session = main.getHibernateTemplate().getSessionFactory().openSession();
//		Clazz c2 = (Clazz) session.get(Clazz.class, "8a81a97c4471c661014471c669360002");
//		//Clazz c2 = (Clazz) main.getHibernateTemplate().get(Clazz.class, "8a81a97c4471c661014471c669360002");
//		Hibernate.initialize(c2.getSet());
//		
//		System.out.println("11111111111111111111111");
//		session.close();
//		Set<Student> sss =  c2.getSet();
//		System.out.println("22222222222222222");
//		for(Student s: sss){
//			
//			System.out.println(s.getName());
//		}
		main.test();
		//main.getHibernateTemplate().delete(c2);
	}
}

 

级联保存

方法1：自动维护两表关系，mappedby 为被拥维护方，即对应的student为维护方


 

  1. Student s1 = new Student();
  2.         Student s2 = new Student();
  3.         Clazz c1 = new Clazz();
  4.         c1.setName(“1班”);
  5.         s1.setName(“z1″);
  6.         s1.setClazz(c1);
  7.         s2.setName(“z2″);
  8.         s2.setClazz(c1);
  9.         TestMain main = (TestMain)SpringBeanUtil.getBean(“testMain”);
  10.         main.getHibernateTemplate().save(s1);
  11.         main.getHibernateTemplate().save(s2);
Student s1 = new Student();
		Student s2 = new Student();
		Clazz c1 = new Clazz();
		c1.setName("1班");
		s1.setName("z1");
		s1.setClazz(c1);
		s2.setName("z2");
		s2.setClazz(c1);
		TestMain main = (TestMain)SpringBeanUtil.getBean("testMain");
		main.getHibernateTemplate().save(s1);
		main.getHibernateTemplate().save(s2);

 

 

方法2：手动维护，两方都需要set对应对方的变量

 

  1. Student s1 = new Student();
  2.         Student s2 = new Student();
  3.         Clazz c1 = new Clazz();
  4.         c1.setName(“1班”);
  5.         s1.setName(“z1″);
  6.         s1.setClazz(c1);
  7.         s2.setName(“z2″);
  8.         s2.setClazz(c1);
  9.         Set<Student> set = new HashSet<Student>();
  10.         set.add(s1);set.add(s2);
  11.         c1.setSet(set);
  12.         TestMain main = (TestMain)SpringBeanUtil.getBean(“testMain”);
  13.         main.getHibernateTemplate().save(c1);
Student s1 = new Student();
		Student s2 = new Student();
		Clazz c1 = new Clazz();
		c1.setName("1班");
		s1.setName("z1");
		s1.setClazz(c1);
		s2.setName("z2");
		s2.setClazz(c1);
		Set<Student> set = new HashSet<Student>();	
		set.add(s1);set.add(s2);
		c1.setSet(set);
		TestMain main = (TestMain)SpringBeanUtil.getBean("testMain");
		main.getHibernateTemplate().save(c1);

关于延迟加载：

 

http://blog.csdn.net/z69183787/article/details/20049409

http://blog.csdn.net/z69183787/article/details/17136627

关于mappedby关键字 及一对多 更多的解释：

http://blog.csdn.net/z69183787/article/details/8197106

http://blog.csdn.net/z69183787/article/details/18615577

http://blog.csdn.net/z69183787/article/details/20052327