Hibernate访问多个数据库的设计思路:利用 Hibernate中config = new Configuration().configure(configFile);可以加载不同数据库配置信息的原理,编写一个数据库操作类,再编写一个数据库管理程序[map],将加载的数据库连接实例put早数据库管理程序中,具体实现见下面:
Hibernate访问多个数据库步骤一:hibernate配置文件
localhost.cfg.xml
- < ?xml version="1.0" encoding="utf-8"?>
- < !DOCTYPE hibernate-configuration
- PUBLIC "-//Hibernate/Hibernate Configuration DTD//EN"
- "http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">
- < hibernate-configuration>
- < session-factory >
- < !-- local connection properties -->
- < property name="hibernate.connection.url">jdbc:mysql://localhost:3306/bookshop?zeroDateTimeBehavior=convertToNull< /property>
- < property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver< /property>
- < property name="hibernate.connection.username">root< /property>
- < property name="hibernate.connection.password">12345678< /property>
- < !-- property name="hibernate.connection.pool_size">< /property -->
- < !-- dialect for MySQL -->
- < property name="dialect">org.hibernate.dialect.MySQLDialect< /property>
- < property name="hibernate.show_sql">true< /property>
- < property name="hibernate.transaction.factory_class">org.hibernate.transaction.JDBCTransactionFactory< /property>
- < property name="hbm2ddl.auto">update< /property>
- < mapping resource="org/jskyme/data/local/po/Shop.hbm.xml"/>
- < /session-factory>
- < /hibernate-configuration>
data_server.cfg.xml
- < ?xml version="1.0" encoding="utf-8"?>
- < !DOCTYPE hibernate-configuration
- PUBLIC "-//Hibernate/Hibernate Configuration DTD//EN"
- "http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">
- < hibernate-configuration>
- < session-factory >
- < !-- local connection properties -->
- < property name="hibernate.connection.url">jdbc:mysql://192.168.0.10:3306/bookshop?zeroDateTimeBehavior=convertToNull< /property>
- < property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver< /property>
- < property name="hibernate.connection.username">root< /property>
- < property name="hibernate.connection.password">12345678< /property>
- < !-- property name="hibernate.connection.pool_size">< /property -->
- < !-- dialect for MySQL -->
- < property name="dialect">org.hibernate.dialect.MySQLDialect< /property>
- < property name="hibernate.show_sql">true< /property>
- < property name="hibernate.transaction.factory_class">org.hibernate.transaction.JDBCTransactionFactory< /property>
- < property name="hbm2ddl.auto">update< /property>
- < mapping resource="org/jskyme/data/local/po/Shop.hbm.xml"/>
- < /session-factory>
- < /hibernate-configuration>
Hibernate访问多个数据库步骤二:数据库访问类:
数据库管理类:DataBaseManager
- package org.jskyme.hibernate.util;
- import java.util.HashMap;
- public class DataBaseManager extends HashMap {
- private static final long serialVersionUID = 6491666983237498097L;
- private static DataBaseManager inst = new DataBaseManager();
- public static DataBaseManager getInst() {
- return inst;
- }
- public SessionManager get(Object key) {
- return (SessionManager) super.get(key);
- }
- @Override
- public Object put(Object key, Object value) {
- return super.put(key, value);
- }
- public static void setInst(DataBaseManager inst) {
- DataBaseManager.inst = inst;
- }
- }
Hibernate连接数据库操作类:
- package org.jskyme.hibernate.util;
- import java.util.List;
- import org.hibernate.Criteria;
- import org.hibernate.Query;
- import org.hibernate.SQLQuery;
- import org.hibernate.Session;
- import org.hibernate.SessionFactory;
- import org.hibernate.Transaction;
- import org.hibernate.cfg.Configuration;
- public final class SessionManager {
- private Configuration config;
- private SessionFactory sessionFactory;
- private Session session;
- public Criteria createCriteria(Class persistentClass) {
- return session.createCriteria(persistentClass);
- }
- private void buildSession() {
- sessionFactory = config.buildSessionFactory();
- session = sessionFactory.openSession();
- }
- public SessionManager(String configFile) {
- config = new Configuration().configure(configFile);
- buildSession();
- }
- public Session getSession() {
- return session;
- }
- public void save(Object obj) {
- Transaction tx = session.beginTransaction();
- session.save(obj);
- tx.commit();
- }
- public Object load(Class clas, Integer priId) {
- return session.get(clas, priId);
- }
- public Query findbyhql(String hql) {
- return session.createQuery(hql);
- }
- public List pageSizeByhql(String hql) {
- return findbyhql(hql).list();
- }
- public SQLQuery findbysql(String sql) {
- return session.createSQLQuery(sql);
- }
- public void update(Object obj) {
- Transaction tx = session.beginTransaction();
- session.saveOrUpdate(obj);
- tx.commit();
- }
- public void delete(Class clas, Integer inte) {
- session.delete(load(clas, inte));
- }
- public void delete(Object obj) {
- session.delete(obj);
- }
- public void deletebyhql(String hql) {
- Query query = session.createQuery(hql);
- query.executeUpdate();
- }
- public Query createQuery(String hql) {
- return session.createQuery(hql);
- }
- }
Hibernate访问多个数据库步骤三:测试类
- package org.jskyme.data.test;
- import junit.framework.TestCase;
- import org.hibernate.Query;
- import org.jskyme.hibernate.util.DataBaseManager;
- import org.jskyme.hibernate.util.SessionManager;
- public class DataBaseManagerTest extends TestCase {
- DataBaseManager dbm = DataBaseManager.getInst();
- public void testDatabase() {
- setDatabase();
- SessionManager tempSess = dbm.get("dataLocal");
- Query query = tempSess.createQuery("from Shop");
- query.list();
- SessionManager tempSess27 = dbm.get("dateManage");
- Query query27 = tempSess27.createQuery("from Shop");
- query27.list();
- }
- private void setDatabase() {
- SessionManager dateManageLocal = new SessionManager("localhost.cfg.xml");
- SessionManager dateManage27 = new SessionManager("data_server.cfg.xml");
- dbm.put("dateManage", dateManage27);
- dbm.put("dataLocal", dateManageLocal);
- }
- }
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