在Servlet中可访问Spring bean对象，但是不能直接以注入的方式引用

在Servlet中使用注解的方式引用Spring bean对象，会报空指针，因此可以在init()方法中通过WebApplicationContextUtils.getWebApplicationContext(servletContext)获取Spring,
代码如下：

package zttc.itat.user.servlet;

import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import org.apache.log4j.Logger;
import org.jbpm.api.RepositoryService;
import org.springframework.web.context.WebApplicationContext;
import org.springframework.web.context.support.WebApplicationContextUtils;

public class InitJbpmProcessServlet extends HttpServlet {
private static final long serialVersionUID = 1L;

//@Autowired
//RepositoryService repositoryService;

public InitJbpmProcessServlet() {
super();
}

public void init() throws ServletException {
Logger logger = Logger.getLogger(this.getClass());
try {
ServletContext servletContext = this.getServletContext();
WebApplicationContext ctx = WebApplicationContextUtils.getWebApplicationContext(servletContext);
RepositoryService repositoryService = (RepositoryService) ctx.getBean("repositoryService");

//流程部署
repositoryService.createDeployment().addResourceFromClasspath("leave.jpdl.xml").deploy();
logger.info("---流程加载结束---");
} catch (Exception e) {
e.printStackTrace();
}
}
}