spring與hibernate 對不同數據源的切換

因項目的需要，需在一個tomcat 中實現不同數據源間切換，現將實現與大家分享，請各位不吝賜教！

 

首先，配制applicationContext.xml

<bean id="dataSource1" class="com.mchange.v2.c3p0.ComboPooledDataSource" destroy-method="close"> .......... 略去部分因人而異 </bean> <bean id="dataSource2" class="com.mchange.v2.c3p0.ComboPooledDataSource" destroy-method="close"> ............... 略去部分因人而異 </bean><bean id="dynamicDataSource" class="com.delta.mes.common.DynamicDataSource"> <property name="dataSource"> <ref bean="dataSource1"/>默認為dataSource1 </property> </bean> <bean id="sessionFactory" class="org.springframework.orm.hibernate3.LocalSessionFactoryBean" destroy-method="close"> <property name="dataSource"> <ref bean="dynamicDataSource" /> </property> ............... 略去部分因人而異 </bean> <bean id="transactionManager" class="org.springframework.orm.hibernate3.HibernateTransactionManager"> <property name="sessionFactory"> <ref local="sessionFactory" /> </property> </bean> <bean id="jdbcExceptionTranslator" class="org.springframework.jdbc.support.SQLErrorCodeSQLExceptionTranslator"> <property name="dataSource"> <ref bean="dynamicDataSource" /> </property> </bean> <bean id="hibernateTemplate" class="org.springframework.orm.hibernate3.HibernateTemplate"> <property name="sessionFactory"> <ref bean="sessionFactory" /> </property> <property name="jdbcExceptionTranslator"> <ref bean="jdbcExceptionTranslator" /> </property> </bean>//以下部份因人而異<bean id="loginService" class="com.delta.mes.serviceImpl.LoginServiceImpl"> <property name="loginDAO"> <ref bean="loginDAO" /> </property> </bean> <bean id="loginDAO" class="com.delta.mes.daoImpl.LoginDAOImpl"> <property name="hibernateTemplate"> <ref bean="hibernateTemplate" /> </property> </bean>  

其次，DynamicDataSource類實現（裝飾(Decorator)類）

 package com.delta.mes.common;import java.io.PrintWriter;import java.sql.Connection;import java.sql.SQLException;import javax.sql.DataSource;import org.apache.commons.logging.Log;import org.apache.commons.logging.LogFactory;import org.springframework.beans.BeansException;import org.springframework.beans.factory.NoSuchBeanDefinitionException;import org.springframework.context.ApplicationContext;import org.springframework.context.ApplicationContextAware;public class DynamicDataSource implements DataSource, ApplicationContextAware {private static final Log log = LogFactory.getLog(DynamicDataSource.class);private ApplicationContext applicationContext = null;private DataSource dataSource = null;/* * (non-Javadoc) * * @see javax.sql.DataSource#getConnection() * */public void setApplicationContext(ApplicationContext applicationContext)throws BeansException {this.applicationContext = applicationContext;}public DataSource getDataSource() {String dataSourceName = null;Object ds = General.getSession("currentPool");if (ds != null) {dataSourceName = ds.toString();}try {if (dataSourceName == null) {return this.dataSource;}return (DataSource) this.applicationContext.getBean(dataSourceName);} catch (NoSuchBeanDefinitionException ex) {ex.printStackTrace();return null;}}public void setDataSource(DataSource dataSource) {this.dataSource = dataSource;}public Connection getConnection() throws SQLException {return getDataSource().getConnection();}/* * (non-Javadoc) * * @see javax.sql.DataSource#getConnection(java.lang.String, * java.lang.String) */public Connection getConnection(String arg0, String arg1)throws SQLException {return getDataSource().getConnection(arg0, arg1);}/* * (non-Javadoc) * * @see javax.sql.DataSource#getLogWriter() */public PrintWriter getLogWriter() throws SQLException {return getDataSource().getLogWriter();}/* * (non-Javadoc) * * @see javax.sql.DataSource#getLoginTimeout() */public int getLoginTimeout() throws SQLException {return getDataSource().getLoginTimeout();}/* * (non-Javadoc) * * @see javax.sql.DataSource#setLogWriter(java.io.PrintWriter) */public void setLogWriter(PrintWriter arg0) throws SQLException {getDataSource().setLogWriter(arg0);}/* * (non-Javadoc) * * @see javax.sql.DataSource#setLoginTimeout(int) */public void setLoginTimeout(int arg0) throws SQLException {getDataSource().setLoginTimeout(arg0);}public boolean isWrapperFor(Class<?> iface) throws SQLException {// TODO Auto-generated method stubreturn getDataSource().isWrapperFor(iface);}public <T> T unwrap(Class<T> iface) throws SQLException {// TODO Auto-generated method stubreturn getDataSource().unwrap(iface);}}

 

最后 , 以下是jsf 中General 類中session 的實現

 package com.delta.mes.common;import javax.faces.context.ExternalContext;import javax.faces.context.FacesContext;import javax.servlet.http.Cookie;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import javax.servlet.http.HttpSession;/** * * @author SIMON.DENG * */public class General {private static final String COOKIE_PATH = "/ExSFCS";public static final String ExcelReport = "ExcelReport";public static Object getSession(String key) {ExternalContext obj = getExternalContext();if (obj != null) {HttpSession session = (HttpSession) obj.getSession(true);return session.getAttribute(key);}return null;}public static void removeSession(String key) {HttpSession session = (HttpSession) getExternalContext().getSession(true);((HttpServletRequest) getExternalContext().getRequest()).getSession();session.removeAttribute(key);}public static HttpServletRequest getRequest() {HttpServletRequest request = (HttpServletRequest) getExternalContext().getRequest();return request;}public static void setSession(String key, Object obj) {HttpSession session = (HttpSession) getExternalContext().getSession(true);session.setAttribute(key, obj);}public static ExternalContext getExternalContext() {FacesContext facesContext = FacesContext.getCurrentInstance();ExternalContext externalContext = null;try {if (facesContext != null) {externalContext = facesContext.getExternalContext();}} catch (Exception ex) {System.out.println(ex.getMessage());}return externalContext;}public static String getCookie(String key) {String result = null;HttpServletRequest request = (HttpServletRequest) getExternalContext().getRequest();Cookie[] cookies = request.getCookies();if (cookies != null) {for (Cookie cookie : cookies) {if (cookie.getName().equals(key)) {result = cookie.getValue();break;}}}return result;}public static void setCookie(String key, String value) {HttpServletResponse response = (HttpServletResponse) getExternalContext().getResponse();Cookie cookie = new Cookie(key, value);cookie.setPath(COOKIE_PATH);cookie.setMaxAge(14 * 24 * 60 * 60);response.addCookie(cookie);}}

 

大功告成，只要在登陸時選擇不同的數據源，并保存當前的數據源

General.setSession("currentPool", prama); prama為數據源的參數。