Hibernate映射集合属性2__List、Map、数组、Bag等

SetHashSet 无序,不重复e_usere_user_addressSetiduserIdnameaddress要说明的信息:a:集合表的名称(集合表)b:集合表中的外键(集合外键)c:集合表中的元素列(集合元素)List有序,可重复e_usere_user_addressListiduserIdnameaddressidx要说明的信息:a:集合表的名称(集合表)b:集合表中的外键(集合外键)c:集合表中的元素列(集合元素)e:集合元素的索引列MapHashMap 无序,不重复(以key为准)e_usere_user_addressMapiduserIdnameaddresskey_要说明的信息:a:集合表的名称(集合表)b:集合表中的外键(集合外键)c:集合表中的元素列(集合元素)e:集合元素的键-------------------------------------------------------------------数组有序,可重复e_usere_user_addressArrayiduserIdnameaddressidx要说明的信息:a:集合表的名称(集合表)b:集合表中的外键(集合外键)c:集合表中的元素列(集合元素)e:集合元素的索引列Bag无序,可重复Liste_usere_user_addressBagiduserIdnameaddress要说明的信息:a:集合表的名称(集合表)b:集合表中的外键(集合外键)c:集合表中的元素列(集合元素)使用集合属性时,一定要使用接口,而不能声明为具体的实现类。因为经过Session操作后,集合变成了Hibernate自已的集合实现类。

映射文件

<?xml version="1.0"?><!DOCTYPE hibernate-mapping PUBLIC        "-//Hibernate/Hibernate Mapping DTD 3.0//EN"        "http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd"><!-- 导入包 --><hibernate-mapping package="cn.itcast.e_hbm_collection"><!-- 类名 --><class name="User" table="e_user"><id name="id" type="integer" column="id_"><generator class="native" /></id><property name="name" type="string" column="name_" /><!-- addressSet属性,Set集合 table属性：集合表的名称key子元素：集合外键的列名element子元素：存放集合元素列的信息--><set name="addressSet" table="e_user_addressSet"><key column="userId"></key><element type="string" column="address_"></element></set><!-- addressList属性,List集合 list-index：用于存放索引的列 --><list name="addressList" table="e_user_addressList"><key column="userId" /><list-index column="idx_"></list-index><element type="string" column="address_" /></list><!-- addressArray属性,数组。与List映射基本一致 --><array name="addressArray" table="e_user_addressArray"><key column="userId"></key><index type="string" column="idx_"></index><element type="string" column="address_"></element></array><!-- addressMap属性,Map集合 --><map name="addressMap" table="e_user_addressMap"><key column="userId"></key><map-key type="string" column="key_"></map-key><element type="string" column="address_"></element></map><!-- addressBag属性,Bag集合：无序,可重复。与Set集合的映射基本一致 --><bag name="addressBag" table="e_user_addressBag"><key column="userId"></key><element type="string" column="address_"></element></bag></class></hibernate-mapping>

实体类

package cn.itcast.e_hbm_collection;import java.util.ArrayList;import java.util.HashMap;import java.util.HashSet;import java.util.List;import java.util.Map;import java.util.Set;public class User {private Integer id;private String name;private Set<String> addressSet = new HashSet<String>();// Set集合private List<String> addressList = new ArrayList<String>();// List集合private String[] addressArray;// 数组private Map<String, String> addressMap = new HashMap<String, String>();// Map集合private List<String> addressBag = new ArrayList<String>();// Bag集合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<String> getAddressSet() {return addressSet;}public void setAddressSet(Set<String> addressSet) {this.addressSet = addressSet;}public List<String> getAddressList() {return addressList;}public void setAddressList(List<String> addressList) {this.addressList = addressList;}public String[] getAddressArray() {return addressArray;}public void setAddressArray(String[] addressArray) {this.addressArray = addressArray;}public Map<String, String> getAddressMap() {return addressMap;}public void setAddressMap(Map<String, String> addressMap) {this.addressMap = addressMap;}public List<String> getAddressBag() {return addressBag;}public void setAddressBag(List<String> addressBag) {this.addressBag = addressBag;}}

保存获取操作类

package cn.itcast.e_hbm_collection;import java.util.Arrays;import java.util.HashSet;import java.util.Set;import org.hibernate.Session;import org.hibernate.SessionFactory;import org.hibernate.Transaction;import org.hibernate.cfg.Configuration;import org.junit.Test;public class App {private static SessionFactory sessionFactory = new Configuration()//.configure()//.addClass(User.class)//.buildSessionFactory();@Testpublic void testSave() throws Exception {Session session = sessionFactory.openSession();Transaction tx = null;try {tx = session.beginTransaction();// ------------------------------------// 操作Set<String> set = new HashSet<String>();set.add("骆家庄东苑");set.add("文一新西路");// 构建对象User user = new User();user.setName("李四");// >> Set集合 user.getAddressSet().add("新青年厂场"); user.getAddressSet().add("新塘路");// >> List集合 user.getAddressList().add("新青年厂场"); user.getAddressList().add("新塘路"); user.getAddressList().add("新塘路");// >> 数组 String[] string = { "新青年厂场", "新塘路", "新塘路" }; user.setAddressArray(string);// >> Map集合 user.getAddressMap().put("公司", "新青年厂场"); user.getAddressMap().put("家庭", "骆家庄东苑");// >> Bag集合user.getAddressBag().add("新青年厂场");user.getAddressBag().add("新塘路");user.getAddressBag().add("新塘路");// 保存session.save(user);// ------------------------------------tx.commit();} catch (RuntimeException e) {tx.rollback();throw e;} finally {session.close();}}@Testpublic void testGet() throws Exception {Session session = sessionFactory.openSession();Transaction tx = null;try {tx = session.beginTransaction();// ------------------------------------// 获取数据User user = (User) session.get(User.class, 1);// 显示信息System.out.println(user.getId());System.out.println(user.getName());// >> Set集合 System.out.println(user.getAddressSet());// >> List集合 System.out.println(user.getAddressList().get(0));// >> 数组 System.out.println(Arrays.toString(user.getAddressArray()));// >> Map集合 System.out.println(user.getAddressMap());// >> Bag集合System.out.println(user.getAddressBag());// ------------------------------------tx.commit();} catch (RuntimeException e) {tx.rollback();throw e;} finally {session.close();}}}