1.配置xml檔案

applicationContext.xml
<bean id="defaultDataSource" class="org.apache.commons.dbcp.BasicDataSource" destroy-method="close">
  <property name="driverClassName" value="${default.driver}" />
  <property name="url" value="${default.url}" />
  <property name="username" value="${default.username}" />
  <property name="password" value="${default.password}" />
 </bean>
 <bean id="dataSource" class="com.ceict.ems.common.db.DynamicDataSource">
  <property name="targetDataSources">
   <map>
    <entry key="default" value-ref="defaultDataSource" />
   </map>
  </property>
 </bean>
 

2.編寫動態連線的介面:

public class DynamicDataSource extends AbstractRoutingDataSource {
    private Map<Object, Object> _targetDataSources;
    @Override
    protected Object determineCurrentLookupKey() {
        return DataSourceContextHolder.getDataSource();
    }
    public void setTargetDataSources(Map<Object, Object> targetDataSources) {
        this._targetDataSources = targetDataSources;
        super.setTargetDataSources(targetDataSources);
        afterPropertiesSet();
    }
    public String getDbtype(String key) {
        String driver = ((BasicDataSource) _targetDataSources.get(key))
                .getDriverClassName();
        if ("oracle.jdbc.driver.OracleDriver".equals(driver)) {
            return "oracle";
        } else if ("com.mysql.jdbc.Driver".equals(driver)) {
            return "mysql";
        }
        return null;
    }
    public void addTargetDataSource(String key, DataSource dataSource) {
        _targetDataSources.put(key, dataSource);
        this.setTargetDataSources(_targetDataSources);
    }
    public static DataSource createDataSource(String driverClassName,
            String url, String username, String password) {
        BasicDataSource dataSource = new BasicDataSource();
        dataSource.setDriverClassName(driverClassName);
        dataSource.setUrl(url);
        dataSource.setUsername(username);
        dataSource.setPassword(password);
        dataSource.setTestWhileIdle(true);
        if ("oracle.jdbc.driver.OracleDriver".equals(driverClassName)) {
            dataSource.setValidationQuery("SELECT 1 FROM DUAL");
        } else if ("com.mysql.jdbc.Driver".equals(driverClassName)) {
            dataSource.setValidationQuery("SELECT NOW()");
        }
        return dataSource;
    }
}
 
 

DynamicDataSource dynamicDataSource = ApplicationUtil
                .getBean(DynamicDataSource.class);
        BasicDataSource dataSource = DynamicDataSource.createDataSource(driverClassName,url,userName,password)
        
        dynamicDataSource.addTargetDataSource("dbkey", dataSource );
       
       
        DataSourceContextHolder.setDataSource("dbkey");
        // 通過以上語句可以將資料庫連線配置修改為當前設定的
         //執行自己的DAO方法
 
 
        DataSourceContextHolder.clearDataSource();//恢復資料庫的配置為applicationContext.xml預設的配置