spring+Hibernate 实现多个数据库管理的问题

import java.sql.SQLException;
import org.springframework.jdbc.datasource.lookup.AbstractRoutingDataSource;
/**

• 建立动态数据源类，这个类继承AbstractRoutingDataSource
• @author sky
• @since 1.0
• @see org.springframework.jdbc.datasource.lookup.AbstractRoutingDataSource
• */

1. class DynamicDataSource extends AbstractRoutingDataSource {

protected Object determineCurrentLookupKey() {
return ContextHolder.getType();
}

public T unwrap(Class iface) throws SQLException {
// TODO Auto-generated method stub
return null;
}

public boolean isWrapperFor(Class<?> iface) throws SQLException {
// TODO Auto-generated method stub
return false;
}

}