Vaadin和Spring集成-@Inject不起作用 [英] Vaadin and Spring integration - @Inject doesn't work

问题描述

我正在尝试将Vaadin与Spring集成在一起.在我的主要Vaadin应用程序类中，我有:

I'm trying to integrate Vaadin with Spring. In my main Vaadin application class I have:

public class MyVaadinApplication extends UI {

@Inject
private PrivatePersonBo privatePersonBo;

@Override
public void init(VaadinRequest request) {
    Layout layout = new FormLayout();
    layout.setCaption("New Private Person");
    setContent(layout);

    ApplicationContext appContext = new ClassPathXmlApplicationContext("resources/spring/Context.xml");
    appContext.getBean(MyVaadinApplication.class);
    PrivatePersonBo privatePersonBo = (PrivatePersonBo) appContext.getBean("privatePersonBo");
    PrivatePerson existingEmployee = privatePersonBo.findByName("TestUserName");

}

}

如果我直接从上下文中获取bean，那么我会收到bean，但是如果我注释了从appContext中接收bean的行，那么@Inject注释将不起作用，并且会得到NullPointerException.我的部署描述符如下:

If I get bean from context directly I recieve bean, however If I comment line which recieves bean from appContext then @Inject annotation doesn't work and I get NullPointerException. My deployment descriptor is below:

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://java.sun.com/xml/ns/javaee"
     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
     xsi:schemaLocation="http://java.sun.com/xml/ns/javaee
      http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd"
     version="3.0">

<context-param>
    <param-name>contextConfigLocation</param-name>
    <param-value>classpath*:resources/spring/Context.xml</param-value>
</context-param>

<listener>
    <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>

<servlet>
    <servlet-name>VaadinApplicationServlet</servlet-name>
    <servlet-class>com.vaadin.server.VaadinServlet</servlet-class>
    <init-param>
        <param-name>UI</param-name>
        <param-value>pl.adamsalata.MyVaadinApplication</param-value>
    </init-param>
</servlet>
<servlet-mapping>
    <servlet-name>VaadinApplicationServlet</servlet-name>
    <url-pattern>/*</url-pattern>
</servlet-mapping>

有什么建议吗?

推荐答案

您可以通过两个简单的步骤将Vaadin 7与Spring集成:

You can integrate Vaadin 7 with Spring in two simple steps:

1)创建一个在春季上下文中查找UIs的UIProvider:

1) Create a UIProvider that lookup UIs in spring context:

public class SpringUIProvider extends DefaultUIProvider {

     @Override
     public UI createInstance(UICreateEvent event) {
         ApplicationContext ctx =  WebApplicationContextUtils
              .getWebApplicationContext(VaadinServlet.getCurrent().getServletContext());

         return ctx.getBean(event.getUIClass());
     }
}

2)在web.xml中声明UIProvider :

2) Declare the UIProvider in web.xml:

<context-param>
                <param-name>UIProvider</param-name>
                <param-value>org.example.SpringUIProvider</param-value>
</context-param>

并且请记住对UI类使用 prototype 范围.

And remember to use prototype scope for UI classes.

这篇关于Vaadin和Spring集成-@Inject不起作用的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！