如何使用gradle包装器添加javadoc

Question

我正在使用Pro Spring 5 https://github.com/Apress/pro-spring-5书中的代码，该书是多模块项目，即使我添加了

apply plugin: 'java'
apply plugin: 'idea'

idea {
    module {
        downloadJavadoc = true
        downloadSources = true
    }
}

对于许多build.gradle文件，它们也都具有最高的层次结构，但是我没有看到任何Javadoc，例如，当我想看到javadoc注释@SpringBootApplication时，键入ctrl + q，而我没有看到文档但是

org.springframework.boot.autoconfigure @Target({ElementType.TYPE}) 

    @Retention(RetentionPolicy.RUNTIME) 
    @Documented 
    @Inherited 
    @SpringBootConfiguration 
    @EnableAutoConfiguration 
    @ComponentScan(excludeFilters = {@org.springframework.context.annotation.ComponentScan.Filter(type = org.springframework.context.annotation.FilterType.CUSTOM, classes = {org.springframework.boot.context.TypeExcludeFilter.class}),@org.springframework.context.annotation.ComponentScan.Filter(type = org.springframework.context.annotation.FilterType.CUSTOM, classes = {org.springframework.boot.autoconfigure.AutoConfigurationExcludeFilter.class})}) 
    public interface SpringBootApplication
    extends annotation.Annotation

      Gradle: org.springframework.boot:spring-boot-autoconfigure:2.0.6.RELEASE