Spring boot注解方式配置Servlet为何扫描不到

来源：互联网 2023-03-17 00:18:25 版权归原作者所有，如有侵权，请联系我们

我在进行基于Spring boot方式进行配置Servlet时，发现系统并不能扫描并识别出我所配置的Servlet类，后来经过分析，调整了注解的详细方式，最后解决了问题，这里就给出我是如何解决Spring boot框架上使用注解方式配置Servlet时导致系统无法扫描出我定义的Servlet的原因和解决方式

工具/原料

Spring boot

方法/步骤

创建一个Maven工程项目，并在该工程的Pom文件中增加如下的包依赖

project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">

modelVersion>4.0.0/modelVersion>

groupId>fantasy/groupId>

artifactId>balckbox/artifactId>

version>0.0.1-SNAPSHOT/version>

parent>

groupId>org.springframework.boot/groupId>

artifactId>spring-boot-starter-parent/artifactId>

version>1.5.9.RELEASE/version>

/parent>

dependencies>

dependency>

groupId>org.springframework.boot/groupId>

artifactId>spring-boot-starter-thymeleaf/artifactId>

/dependency>

dependency>

groupId>org.springframework.boot/groupId>

artifactId>spring-boot-devtools/artifactId>

optional>true/optional>

/dependency>

/dependencies>

properties>

java.version>1.8/java.version>

/properties>

build>

plugins>

plugin>

groupId>org.springframework.boot/groupId>

artifactId>spring-boot-maven-plugin/artifactId>

/plugin>

/plugins>

/build>

/project>

Spring boot注解方式配置Servlet为何扫描不到

创建一个Servlet服务类(FantasyServlet.java)，对外提供WEB Servlet服务，需要使用到注解WebServlet

package fantasy.servlet;

import java.io.IOException;

import java.io.PrintWriter;

import java.util.Date;

import javax.servlet.ServletException;

import javax.servlet.annotation.WebServlet;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

@WebServlet(urlPatterns="/fantasy/hello")

public class FantasyServlet extends HttpServlet {

private static final long serialVersionUID = 1457739152440306935L;

@Override

protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

System.out.println(">>>>Fantasy Servlet do get request.....");

doPost(req,resp);

}

@Override

protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

System.out.println(">>>>Fantasy Servlet do post request.....");

resp.setContentType("text/html");

resp.setCharacterEncoding("utf-8");

PrintWriter out = resp.getWriter();

out.print("html>body>");

out.print("h1>I am Fantasy from FantasyServlet @" new Date() "/h1>");

out.print("/body>/html>");

out.flush();

out.close();

}

Spring boot注解方式配置Servlet为何扫描不到

创建一个Spring boot应用运行的主类(Application.java)

在主类我们需要使用ServletComponentScan注解和SpringBootApplication注解

package fantasy.main;

import org.springframework.boot.SpringApplication;

import org.springframework.boot.autoconfigure.SpringBootApplication;

import org.springframework.boot.web.servlet.ServletComponentScan;

@SpringBootApplication

@ServletComponentScan

public class Application {

public static void main(String[] args) {

SpringApplication.run(Application.class, args);

}

Spring boot注解方式配置Servlet为何扫描不到

运行Application类，启动Spring boot应用

这时候可以我们观察日志，发现系统并没有扫描到我们配置的servlet：/fantasy/hello

-----------------------------------

2018-01-15 17:07:54.653 INFO 4100 --- [ost-startStop-1] o.a.c.c.C.[Tomcat].[localhost].[/] : Initializing Spring embedded WebApplicationContext

2018-01-15 17:07:54.653 INFO 4100 --- [ost-startStop-1] o.s.web.context.ContextLoader : Root WebApplicationContext: initialization completed in 1423 ms

2018-01-15 17:07:54.811 INFO 4100 --- [ost-startStop-1] o.s.b.w.servlet.ServletRegistrationBean : Mapping servlet: 'dispatcherServlet' to [/]

2018-01-15 17:07:54.814 INFO 4100 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean : Mapping filter: 'characterEncodingFilter' to: [/*]

2018-01-15 17:07:54.815 INFO 4100 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean : Mapping filter: 'hiddenHttpMethodFilter' to: [/*]

2018-01-15 17:07:54.815 INFO 4100 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean : Mapping filter: 'httpPutFormContentFilter' to: [/*]

2018-01-15 17:07:54.815 INFO 4100 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean : Mapping filter: 'requestContextFilter' to: [/*]

2018-01-15 17:07:55.081 INFO 4100 --- [ restartedMain] s.w.s.m.m.a.RequestMappingHandlerAdapter : Looking for @ControllerAdvice: org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext@12d912f: startup date [Mon Jan 15 17:07:53 CST 2018]; root of context hierarchy

2018-01-15 17:07:55.140 INFO 4100 --- [ restartedMai

Spring boot注解方式配置Servlet为何扫描不到