SpringBoot 集成jax-ws无法使用@Autowired 解决方案

继承SpringBeanAutowiringSupport后依然无法使用@Autowired
o.s.w.c.s.SpringBeanAutowiringSupport : Current WebApplicationContext is not available for processing of PortalApplication: Make sure this class gets constructed in a Spring web application. Proceeding without injection.

原因分析

jax-ws 中bean的生命周期管理是不受spring 控制的。所以需要显式继承 SpringBeanAutowiringSupport
来看下实现源码,非常巧妙

/**
     * This constructor performs injection on this instance,
     * based on the current web application context.
     * <p>Intended for use as a base class.
     * @see #processInjectionBasedOnCurrentContext
     */
    public SpringBeanAutowiringSupport() {
        processInjectionBasedOnCurrentContext(this);
    }


    /**
     * Process {@code @Autowired} injection for the given target object,
     * based on the current web application context.
     * <p>Intended for use as a delegate.
     * @param target the target object to process
     * @see org.springframework.web.context.ContextLoader#getCurrentWebApplicationContext()
     */
    public static void processInjectionBasedOnCurrentContext(Object target) {
        Assert.notNull(target, "Target object must not be null");
        WebApplicationContext cc = ContextLoader.getCurrentWebApplicationContext();
        if (cc != null) {
            AutowiredAnnotationBeanPostProcessor bpp = new AutowiredAnnotationBeanPostProcessor();
            bpp.setBeanFactory(cc.getAutowireCapableBeanFactory());
            bpp.processInjection(target);
        }
        else {
            if (logger.isDebugEnabled()) {
                logger.debug("Current WebApplicationContext is not available for processing of " +
                        ClassUtils.getShortName(target.getClass()) + ": " +
                        "Make sure this class gets constructed in a Spring web application. Proceeding without injection.");
            }
        }
    }

从网上搜索到的也基本上都解释了这个方法,但是,在spring boot中是不起作用的。
因为 spring bootServlet Context Initialization 略微不一样

SpringBootServletInitializer.startup() 使用了自定义的ContextLoaderListener,
并没有把创建的rootAppContext传给ContextLoader
所以JAX-WS endpoint 类初始化的时候, SpringBeanAutowiringSupport从ContextLoader.getCurrentWebApplicationContext()取值总是null,@Autowired当然就不能用了。

public abstract class SpringBootServletInitializer implements WebApplicationInitializer {

    @Override
    public void onStartup(ServletContext servletContext) throws ServletException {
        // Logger initialization is deferred in case a ordered
        // LogServletContextInitializer is being used
        this.logger = LogFactory.getLog(getClass());
        WebApplicationContext rootAppContext = createRootApplicationContext(
                servletContext);
        if (rootAppContext != null) {
            servletContext.addListener(new ContextLoaderListener(rootAppContext) {
                @Override
                public void contextInitialized(ServletContextEvent event) {
                    // no-op because the application context is already initialized
                }
            });
        }
        else {
            this.logger.debug("No ContextLoaderListener registered, as "
                    + "createRootApplicationContext() did not "
                    + "return an application context");
        }
    }
}

好了,找到了问题所在,就好解决了,思路如下。

  1. 初始化时把WebApplicationContext存下来
  2. 参考SpringBeanAutowiringSupport 把WebApplicationContext 拿出来,并使用
WebApplicationContextLocator.java

@Configuration
public class WebApplicationContextLocator  implements ServletContextInitializer {

    private static WebApplicationContext webApplicationContext;

    public static WebApplicationContext getCurrentWebApplicationContext() {
        return webApplicationContext;
    }

    /**
     * 在启动时将servletContext 获取出来,后面再读取二次使用。
     * @param servletContext
     * @throws ServletException
     */
    @Override
    public void onStartup(ServletContext servletContext) throws ServletException {
        webApplicationContext = WebApplicationContextUtils.getWebApplicationContext(servletContext);
    }
}
SpringBootBeanAutowiringSupport.java
public abstract class SpringBootBeanAutowiringSupport {

    private static final Log logger = LogFactory.getLog(SpringBootBeanAutowiringSupport.class);


    /**
     * This constructor performs injection on this instance,
     * based on the current web application context.
     * <p>Intended for use as a base class.
     * @see #processInjectionBasedOnCurrentContext
     */
    public SpringBootBeanAutowiringSupport() {
        System.out.println("SpringBootBeanAutowiringSupport.SpringBootBeanAutowiringSupport");
        processInjectionBasedOnCurrentContext(this);
    }


    /**
     * Process {@code @Autowired} injection for the given target object,
     * based on the current web application context.
     * <p>Intended for use as a delegate.
     * @param target the target object to process
     * @see org.springframework.web.context.ContextLoader#getCurrentWebApplicationContext()
     */
    public static void processInjectionBasedOnCurrentContext(Object target) {
        Assert.notNull(target, "Target object must not be null");
        WebApplicationContext cc = WebApplicationContextLocator.getCurrentWebApplicationContext();
        if (cc != null) {
            AutowiredAnnotationBeanPostProcessor bpp = new AutowiredAnnotationBeanPostProcessor();
            bpp.setBeanFactory(cc.getAutowireCapableBeanFactory());
            bpp.processInjection(target);
        }
        else {
            if (logger.isDebugEnabled()) {
                logger.debug("Current WebApplicationContext is not available for processing of " +
                        ClassUtils.getShortName(target.getClass()) + ": " +
                        "Make sure this class gets constructed in a Spring web application. Proceeding without injection.");
            }
        }
    }
}

结论

jax-ws 或类似的应用,直接 使用我们改造后的AutowiringSupport即可
extends SpringBootBeanAutowiringSupport

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