无法在Spring工具套件中解析@GetMapping

Question

我已经在spring工具套件中创建了一个spring项目。

GetMapping cannot be resolved to a type

我的代码是

package tacos;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.GetMapping;
@Controller
public class HomeController 
{
    @GetMapping
    public String home()
    {
        return "home";
    }
}

正如您在这一行中看到的，我已经导入了GetMapping。

import org.springframework.web.bind.annotation.GetMapping;

pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<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>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.1.6.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>sia</groupId>
    <artifactId>taco-cloud</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>taco-cloud</name>
    <description>Taco cloud example</description>

    <properties>
        <java.version>1.8</java.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

</project>

Answer 1

因为您从未将Spring MVC包含到您的项目中，因此它无法解析来自它的类。

您应该在pom.xml中包含spring-boot-starter-web，这将为您传递获得Spring MVC和嵌入式Tomcat：

  <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-web</artifactId>
    </dependency>