我想将现有的web.xml配置迁移到spring-boot.

但是如何正确完成呢？

这是web.xml：

    <listener>
        <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
    </listener> 
    <context-param>
        <param-name>contextConfigLocation</param-name>
        <param-value>WEB-INF/applicationContext.xml</param-value>
    </context-param>
 <servlet>
    <servlet-name>CXFServlet</servlet-name>
        <servlet-class>org.apache.cxf.transport.servlet.CXFServlet</servlet-class>
        <load-on-startup>1</load-on-startup>
    </servlet>
    <servlet-mapping>
        <servlet-name>CXFServlet</servlet-name>
        <url-pattern>/soap/*</url-pattern>
    </servlet-mapping>

如何将其转换为基于注释的spring-boot配置？我尝试了以下方法：
    

@Configuration
@EnableAutoConfiguration
public class AppConfig extends SpringBootServletInitializer {
    @Override
    protected SpringApplicationBuilder configure(SpringApplicationBuilder application) {
        return application.sources(AppConfig.class);
    }


    @Bean
    public CXFServlet cxf() {
        return new CXFServlet();
    }   
}

但是在tomcat上启动时,会引发以下异常：

Caused by: java.lang.NullPointerException: null
    at org.apache.cxf.transport.servlet.CXFNonSpringServlet.destroy(CXFNonSpringServlet.java:184)
    at org.apache.cxf.transport.servlet.CXFServlet.onApplicationEvent(CXFServlet.java:166)
    at org.apache.cxf.transport.servlet.CXFServlet.onApplicationEvent(CXFServlet.java:41)
    at org.springframework.context.event.SimpleApplicationEventMulticaster.multicastEvent(SimpleApplicationEventMulticaster.java:98)
    at org.springframework.context.support.AbstractApplicationContext.publishEvent(AbstractApplicationContext.java:333)
    at org.springframework.context.support.AbstractApplicationContext.finishRefresh(AbstractApplicationContext.java:776)
    at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext.finishRefresh(EmbeddedWebApplicationContext.java:142)
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:485)
    at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext.refresh(EmbeddedWebApplicationContext.java:120)
    at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:648)
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:311)
    at org.springframework.boot.builder.SpringApplicationBuilder.run(SpringApplicationBuilder.java:130)
    at org.springframework.boot.context.web.SpringBootServletInitializer.createRootApplicationContext(SpringBootServletInitializer.java:89)
    at org.springframework.boot.context.web.SpringBootServletInitializer.onStartup(SpringBootServletInitializer.java:51)
    at org.springframework.web.SpringServletContainerInitializer.onStartup(SpringServletContainerInitializer.java:175)
    at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5444)
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)

解决方法:

您应该为CXFServlet使用ServletRegistrationBean.这将确保它已在servlet容器中注册,并允许您配置URL模式等.例如：

@Bean
public ServletRegistrationBean cxf() {
    return new ServletRegistrationBean(new CXFServlet(), "/soap/*");
}