springboot 打成war包發佈到tomcat中過程以及遇到的問題。

1、確定pom文件的打包方式爲war

<packaging>war</packaging>

2、移除掉springboot自帶的tomcat，使用<scope>provided</scope>這個表示最終這個jar包不會被打入到war包中。引入tomcat相關的servlet包。這裏注意下如果項目中有引入servlet-api的包要去掉會和tomcat-servlet-api有衝突。

<dependency>    
         <groupId>org.springframework.boot</groupId>    
         <artifactId>spring-boot-starter-web</artifactId>    
         <version>${spring.boot.version}</version>
 <exclusions>
    <exclusion>
       <groupId>org.springframework.boot</groupId>
       <artifactId>spring-boot-starter-tomcat</artifactId>
    </exclusion>
 </exclusions>
     </dependency>

<dependency>
   <groupId>org.springframework.boot</groupId>
   <artifactId>spring-boot-starter-tomcat</artifactId>
   <version>${spring.boot.version}</version>
   <scope>provided</scope>
</dependency>

<dependency>
   <groupId>org.apache.tomcat</groupId>
   <artifactId>tomcat-servlet-api</artifactId>
   <version>9.0.14</version>
   <scope>provided</scope>
</dependency>

3、在Application類中做如下修改：

這時候本來就已經完事了，但是項目中用到了過濾器，導致放入到tomcat中一直報錯

02-Apr-2020 20:04:52.464 嚴重 [main] org.apache.catalina.core.StandardContext.filterStart 啓動過濾器異常
 javax.naming.NamingException: Cannot create resource instance
    at org.apache.naming.factory.FactoryBase.getObjectInstance(FactoryBase.java:96)
    at javax.naming.spi.NamingManager.getObjectInstance(NamingManager.java:321)
    at org.apache.naming.NamingContext.lookup(NamingContext.java:840)
    at org.apache.naming.NamingContext.lookup(NamingContext.java:159)
    at org.apache.naming.NamingContext.lookup(NamingContext.java:827)
    at org.apache.naming.NamingContext.lookup(NamingContext.java:173)
    at org.apache.catalina.core.DefaultInstanceManager.lookupFieldResource(DefaultInstanceManager.java:584)
    at org.apache.catalina.core.DefaultInstanceManager.processAnnotations(DefaultInstanceManager.java:486)
    at org.apache.catalina.core.DefaultInstanceManager.newInstance(DefaultInstanceManager.java:174)
    at org.apache.catalina.core.DefaultInstanceManager.newInstance(DefaultInstanceManager.java:166)
    at org.apache.catalina.core.ApplicationFilterConfig.<init>(ApplicationFilterConfig.java:105)
    at org.apache.catalina.core.StandardContext.filterStart(StandardContext.java:4511)
    at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5157)
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183)
    at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:713)
    at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:690)
    at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:695)
    at org.apache.catalina.startup.HostConfig.deployWAR(HostConfig.java:978)
    at org.apache.catalina.startup.HostConfig$DeployWar.run(HostConfig.java:1850)
    at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
    at java.util.concurrent.FutureTask.run(FutureTask.java:266)
    at org.apache.tomcat.util.threads.InlineExecutorService.execute(InlineExecutorService.java:75)
    at java.util.concurrent.AbstractExecutorService.submit(AbstractExecutorService.java:112)
    at org.apache.catalina.startup.HostConfig.deployWARs(HostConfig.java:773)
    at org.apache.catalina.startup.HostConfig.deployApps(HostConfig.java:427)
    at org.apache.catalina.startup.HostConfig.start(HostConfig.java:1577)
    at org.apache.catalina.startup.HostConfig.lifecycleEvent(HostConfig.java:309)
    at org.apache.catalina.util.LifecycleBase.fireLifecycleEvent(LifecycleBase.java:123)
    at org.apache.catalina.util.LifecycleBase.setStateInternal(LifecycleBase.java:424)
    at org.apache.catalina.util.LifecycleBase.setState(LifecycleBase.java:367)
    at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:934)
    at org.apache.catalina.core.StandardHost.startInternal(StandardHost.java:831)
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183)
    at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1382)
    at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1372)
    at java.util.concurrent.FutureTask.run(FutureTask.java:266)
    at org.apache.tomcat.util.threads.InlineExecutorService.execute(InlineExecutorService.java:75)
    at java.util.concurrent.AbstractExecutorService.submit(AbstractExecutorService.java:134)
    at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:907)
    at org.apache.catalina.core.StandardEngine.startInternal(StandardEngine.java:262)
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183)
    at org.apache.catalina.core.StandardService.startInternal(StandardService.java:423)
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183)
    at org.apache.catalina.core.StandardServer.startInternal(StandardServer.java:933)
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183)
    at org.apache.catalina.startup.Catalina.start(Catalina.java:637)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at org.apache.catalina.startup.Bootstrap.start(Bootstrap.java:350)
    at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:492)

我這裏想的是既然過濾器有問題，那我把過濾器全部註釋掉不就行了，註釋掉過濾器@Component、@Order和@WebFilter後項目能夠正常訪問，但是過濾器這個功能也就完全用不了了，這肯定是不行的。然後我找了下spring boot 配置Filter過濾器的方法，我自己通過註解的方式是不行的，那就只能是通過@Bean的方式了。

4、在Application中將過濾器的通過bean的方式進行注入（如果沒有使用到過濾器就只有上面三個步驟就行了）。

這時候再次打包放入到tomcat中查找日誌發現過濾器中通過@Resource註解的類都是爲空的，然後報了這個錯誤javax.naming.NamingException: Cannot create resource instance at，也就是還沒被放入到spring容器中。網上有說法說是在Application中加入@ServletComponentScan指到過濾器的類名，這個方法我試了下沒有成功。

5、去掉過濾器中的@Resource通過ApplicationContext context 去Spring容器中取service。

ApplicationContext context = (ApplicationContext)se.getSession().getServletContext().getAttribute(WebApplicationContext.ROOT_WEB_APPLICATION_CONTEXT_ATTRIBUTE); 
ManagerLoginLogService managerLoginLogService = context.getBean(“managerLoginLogService”,ManagerLoginLogService.class);

6、再次打包發佈到tomcat中終於成功了。