I can't install lombok with Gradle.

Event

I added the following two lines to Gradle and ran Gradle, but I got an error.

dependencies {
    compile("org.springframework.boot:spring-boot-starter-web")
    testCompile('org.springframework.boot:spring-boot-starter-test')
    testCompile('com.jayway.jsonpath:json-path')
    compileOnly 'org.projectlombok:lombok:1.18.6' <--add to
    annotationProcessor 'org.projectlombok:lombok:1.18.6' <--add to
}

Error 1

Warning:<i><b>root project 'complete': Unable to resolve additional project configuration.</b>
Details: org.gradle.api.artifacts.ResolveException: Could not resolve all dependencies for configuration ':runtimeClasspath'.
Caused by: org.gradle.internal.resolve.ArtifactResolveException: Could not download spring-boot-starter-web.jar (org.springframework.boot:spring-boot-starter-web:2.1.3.RELEASE): No cached version available for offline mode</i>

Countermeasure 1

I don't know which measure I heard, but I did it from top to bottom and finally succeeded.

1. Check Enable annotation processing. Intellij IDEA -> Preferences -> Compiler -> Annotation Processors

2. Check Enable annotation processing. File -> Other Settings -> Default Settings -> Compiler -> Annotation Processors

3. Install the Lombok plugin Intellij IDEA -> Preferences -> Plugins ->Browse Repositories-> Search for "Lombok"-> install plugin -> Apply and restart IDEA

4. Check Work offline. Intellij IDEA -> Preferences -> Build, Execution, Deployment -> Build Tools -> Gradle

Error 2

After the above measures, when I executed the build, the following error occurred.

Countermeasure 2

The following has been added to pom.xml. Reference: https://tyoshikawa1106.hatenablog.com/entry/2015/11/15/220056

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>com.jayway.jsonpath</groupId>
            <artifactId>json-path</artifactId>
            <scope>test</scope>
        </dependency>
        <!--from here-->
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>1.18.6</version>
            <scope>provided</scope>
        </dependency>
        <!--Add up to here-->
    </dependencies>

The build passed successfully.