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Hibernate訪問多個數據庫的設計思路：利用 Hibernate中config = new Configuration().configure(configFile);可以加載不同數據庫配置信息的原理，編寫一個數據庫操作類，再編寫一個數據庫管理程序[map]，將加載的數據庫連接實例put早數據庫管理程序中，具體實現見下面：

Hibernate訪問多個數據庫步驟一：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訪問多個數據庫步驟二：數據庫訪問類：

數據庫管理類：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連接數據庫操作類：

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訪問多個數據庫步驟三：測試類

1. package org.jskyme.data.test;
3. import junit.framework.TestCase;
5. import org.hibernate.Query;
6. import org.jskyme.hibernate.util.DataBaseManager;
7. import org.jskyme.hibernate.util.SessionManager;
9. public class DataBaseManagerTest extends TestCase {
10. DataBaseManager dbm = DataBaseManager.getInst();
12. public void testDatabase() {
13. ?? setDatabase();
14. ?? SessionManager tempSess = dbm.get("dataLocal");
15. ?? Query query = tempSess.createQuery("from?? Shop");
16. ?? query.list();
17. ??
18. ?? SessionManager tempSess27 = dbm.get("dateManage");
19. ?? Query query27 = tempSess27.createQuery("from Shop");
20. ?? query27.list();
21. }
23. private void setDatabase() {
24. ?? SessionManager dateManageLocal = new SessionManager("localhost.cfg.xml");
25. ?? SessionManager dateManage27 = new SessionManager("data_server.cfg.xml");
26. ?? dbm.put("dateManage", dateManage27);
27. ?? dbm.put("dataLocal", dateManageLocal);
29. }
30. }