关于apache cxf 结合Spring框架开发webservice服务
我在用apache cxf 结合Spring框架开发webservice服务时，遇到一个这样的问题，请大家帮忙解决一下，问题描述如下：

webservice启动配置如下

<beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:jaxws="http://cxf.apache.org/jaxws" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://cxf.apache.org/jaxws http://cxf.apache.org/schemas/jaxws.xsd"><import resource="classpath:META-INF/cxf/cxf.xml" /><import resource="classpath:META-INF/cxf/cxf-extension-soap.xml" /><import resource="classpath:META-INF/cxf/cxf-servlet.xml" /><jaxws:endpoint id="sqlExecuteService"implementor="com.unicom.uniformdata.SqlExecuteServiceImpl"address="/DesServer"></jaxws:endpoint></beans>

com.unicom.uniformdata.SqlExecuteServiceImpl类实现如下

@javax.jws.WebService(                      serviceName = "SqlExecuteServiceService",                      portName = "SqlExecuteServicePort",                      targetNamespace = "http://uniformdata.unicom.com",                      endpointInterface = "com.unicom.uniformdata.SqlExecuteService")                      public class SqlExecuteServiceImpl implements SqlExecuteService {private DaoHelper daoHelper = null;public SqlExecuteServiceImpl() {System.out.println("实例化webservice实现类");this.daoHelper =  GlobalVariable.getInstance().getDaoHelper();}}public DaoHelper getDaoHelper() {return this.daoHelper == null ? (this.daoHelper = (DaoHelper) SpringUtils.getBean("daoHelper")): this.daoHelper;}

其中daoHelper类的配置是通过<bean>配置的，是数据库操作对象。但在Tomcat启动时，是先实例化SqlExecuteServiceImpl，而不是daoHelper，导致SqlExecuteServiceImpl实例化失败，webservice服务启动失败。这个问题怎么解决。对cxf框架也不是很熟，希望大家能帮助解决一下，谢谢！