在Spring应用程序中有许多获取应用程序上下文的方法。这些因素如下:

通过ApplicationContextAware: 进口org.springframework.beans.BeansException; 进口org.springframework.context.ApplicationContext; 进口org.springframework.context.ApplicationContextAware; 公共类AppContextProvider实现了ApplicationContextAware { private ApplicationContext; @Override setApplicationContext(ApplicationContext)抛出BeansException { 这一点。applicationContext = applicationContext; ｝ ｝

这里setApplicationContext(ApplicationContext ApplicationContext)方法将获得ApplicationContext

ApplicationContextAware: 接口，由希望被通知的任何对象实现 它运行的ApplicationContext的。实现此接口 例如，当一个对象需要访问一组 合作bean。

通过Autowired的: @ autowired private ApplicationContext;

这里@Autowired关键字将提供applicationContext。自动连线有一些问题。这将在单元测试时产生问题。

在Spring bean中进行自动装配，如下所示:

@Autowired
private ApplicationContext appContext;

您将得到ApplicationContext对象。

请注意，通过将当前ApplicationContext的任何状态或ApplicationContext本身存储在一个静态变量中(例如使用单例模式)，如果使用Spring-test，您将使您的测试不稳定且不可预测。这是因为Spring-test在同一个JVM中缓存和重用应用程序上下文。例如:

测试运行并使用@ContextConfiguration({"classpath:foo.xml"})进行注释。 测试B运行并使用@ContextConfiguration({"classpath:foo.xml"， "classpath:bar.xml})进行注释 运行测试C，并且使用@ContextConfiguration({"classpath:foo.xml"})进行注释

当测试A运行时，将创建一个ApplicationContext，并且任何实现ApplicationContextAware或自动装配ApplicationContext的bean都可能写入静态变量。

当测试B运行时，同样的事情也会发生，并且静态变量现在指向测试B的ApplicationContext

当测试C运行时，没有bean被创建，因为测试A的TestContext(这里是ApplicationContext)被重用了。现在，您得到了一个指向另一个ApplicationContext的静态变量，而不是当前为您的测试保存bean的ApplicationContext。

即使在添加了@Autowire之后，如果你的类不是一个RestController或Configuration class, applicationContext对象仍然是空的。尝试用下面创建新类，它工作正常:

@Component
public class SpringContext implements ApplicationContextAware{

   private static ApplicationContext applicationContext;

   @Override
    public void setApplicationContext(ApplicationContext applicationContext) throws 
     BeansException {
    this.applicationContext=applicationContext;
   }
 }

然后，你可以在同一个类中根据你的需要实现一个getter方法，比如通过:

    applicationContext.getBean(String serviceName,Interface.Class)

我知道这个问题已经有了答案，但是我想分享一下我用来检索Spring Context的Kotlin代码。

我不是专家，所以我愿意接受批评、评论和建议:

https://gist.github.com/edpichler/9e22309a86b97dbd4cb1ffe011aa69dd

package com.company.web.spring

import com.company.jpa.spring.MyBusinessAppConfig
import org.springframework.beans.factory.annotation.Autowired
import org.springframework.context.ApplicationContext
import org.springframework.context.annotation.AnnotationConfigApplicationContext
import org.springframework.context.annotation.ComponentScan
import org.springframework.context.annotation.Configuration
import org.springframework.context.annotation.Import
import org.springframework.stereotype.Component
import org.springframework.web.context.ContextLoader
import org.springframework.web.context.WebApplicationContext
import org.springframework.web.context.support.WebApplicationContextUtils
import javax.servlet.http.HttpServlet

@Configuration
@Import(value = [MyBusinessAppConfig::class])
@ComponentScan(basePackageClasses  = [SpringUtils::class])
open class WebAppConfig {
}

/**
 *
 * Singleton object to create (only if necessary), return and reuse a Spring Application Context.
 *
 * When you instantiates a class by yourself, spring context does not autowire its properties, but you can wire by yourself.
 * This class helps to find a context or create a new one, so you can wire properties inside objects that are not
 * created by Spring (e.g.: Servlets, usually created by the web server).
 *
 * Sometimes a SpringContext is created inside jUnit tests, or in the application server, or just manually. Independent
 * where it was created, I recommend you to configure your spring configuration to scan this SpringUtils package, so the 'springAppContext'
 * property will be used and autowired at the SpringUtils object the start of your spring context, and you will have just one instance of spring context public available.
 *
 *Ps: Even if your spring configuration doesn't include the SpringUtils @Component, it will works tto, but it will create a second Spring Context o your application.
 */
@Component
object SpringUtils {

        var springAppContext: ApplicationContext? = null
    @Autowired
    set(value) {
        field = value
    }



    /**
     * Tries to find and reuse the Application Spring Context. If none found, creates one and save for reuse.
     * @return returns a Spring Context.
     */
    fun ctx(): ApplicationContext {
        if (springAppContext!= null) {
            println("achou")
            return springAppContext as ApplicationContext;
        }

        //springcontext not autowired. Trying to find on the thread...
        val webContext = ContextLoader.getCurrentWebApplicationContext()
        if (webContext != null) {
            springAppContext = webContext;
            println("achou no servidor")
            return springAppContext as WebApplicationContext;
        }

        println("nao achou, vai criar")
        //None spring context found. Start creating a new one...
        val applicationContext = AnnotationConfigApplicationContext ( WebAppConfig::class.java )

        //saving the context for reusing next time
        springAppContext = applicationContext
        return applicationContext
    }

    /**
     * @return a Spring context of the WebApplication.
     * @param createNewWhenNotFound when true, creates a new Spring Context to return, when no one found in the ServletContext.
     * @param httpServlet the @WebServlet.
     */
    fun ctx(httpServlet: HttpServlet, createNewWhenNotFound: Boolean): ApplicationContext {
        try {
            val webContext = WebApplicationContextUtils.findWebApplicationContext(httpServlet.servletContext)
            if (webContext != null) {
                return webContext
            }
            if (createNewWhenNotFound) {
                //creates a new one
                return ctx()
            } else {
                throw NullPointerException("Cannot found a Spring Application Context.");
            }
        }catch (er: IllegalStateException){
            if (createNewWhenNotFound) {
                //creates a new one
                return ctx()
            }
            throw er;
        }
    }
}

现在，spring上下文是公开可用的，能够独立于上下文调用相同的方法(junit测试，bean，手动实例化类)，就像下面这个Java Servlet:

@WebServlet(name = "MyWebHook", value = "/WebHook")
public class MyWebServlet extends HttpServlet {


    private MyBean byBean
            = SpringUtils.INSTANCE.ctx(this, true).getBean(MyBean.class);


    public MyWebServlet() {

    }
}

SpringApplicationContext.java

import org.springframework.beans.BeansException;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;

/**
 * Wrapper to always return a reference to the Spring Application 
Context from
 * within non-Spring enabled beans. Unlike Spring MVC's 
WebApplicationContextUtils
 * we do not need a reference to the Servlet context for this. All we need is
 * for this bean to be initialized during application startup.
 */
public class SpringApplicationContext implements 
ApplicationContextAware {

  private static ApplicationContext CONTEXT;

  /**
   * This method is called from within the ApplicationContext once it is 
   * done starting up, it will stick a reference to itself into this bean.
  * @param context a reference to the ApplicationContext.
  */
  public void setApplicationContext(ApplicationContext context) throws BeansException {
    CONTEXT = context;
  }

  /**
   * This is about the same as context.getBean("beanName"), except it has its
   * own static handle to the Spring context, so calling this method statically
   * will give access to the beans by name in the Spring application context.
   * As in the context.getBean("beanName") call, the caller must cast to the
   * appropriate target class. If the bean does not exist, then a Runtime error
   * will be thrown.
   * @param beanName the name of the bean to get.
   * @return an Object reference to the named bean.
   */
  public static Object getBean(String beanName) {
    return CONTEXT.getBean(beanName);
  }
}

来源:http://sujitpal.blogspot.de/2007/03/accessing-spring-beans-from-legacy-code.html