添加idea插件后评估:app项目时出现Value is null错误

环境信息 #

• IntelliJ IDEA 2022.2（社区版）
• Java 8

错误场景 #

在build.gradle中配置了如下内容：

plugins {
    id 'application'
    id "com.nocwriter.runsql" version "1.0.3"
    id 'idea'
    id "io.spring.dependency-management" version "1.0.11.RELEASE"
}
apply plugin: "io.spring.dependency-management"

group = 'com.myproject'
version = '2.0.6'

sourceCompatibility = JavaVersion.VERSION_1_8
targetCompatibility = JavaVersion.VERSION_1_8

idea {
    project {
        languageLevel = JavaVersion.VERSION_1_8
    }
    module {
        downloadJavadoc = true
        downloadSources = true
    }
}

执行构建时，在project {所在行（第31行）触发错误，错误信息如下：

FAILURE: Build failed with an exception.

• Where:
  Build file '/myproject/app/build.gradle' line: 31

• What went wrong:
  A problem occurred evaluating project ':app'.

Value is null

解决方法 #

1. 替换idea.project配置方式 #

idea.project块的配置容易因上下文模型实例缺失报错，直接通过编译任务设置语言级别即可达到同样效果，保留idea.module的配置：

plugins {
    id 'application'
    id "com.nocwriter.runsql" version "1.0.3"
    id 'idea'
    id "io.spring.dependency-management" version "1.0.11.RELEASE"
}
apply plugin: "io.spring.dependency-management"

group = 'com.myproject'
version = '2.0.6'

sourceCompatibility = JavaVersion.VERSION_1_8
targetCompatibility = JavaVersion.VERSION_1_8

// 直接通过编译任务设置语言级别，替代idea.project块
tasks.withType(JavaCompile) {
    options.compilerArgs += ['-source', '1.8', '-target', '1.8']
}

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

2. 检查Gradle版本兼容性 #

Java 8仅支持Gradle 6.x、7.x版本，如果你用的是Gradle 8+版本，会出现兼容性问题，建议降级到Gradle 7.6.x版本（最后支持Java8的Gradle版本），同时确保Gradle版本与IDEA内置的Gradle插件版本匹配。

3. 清理Gradle缓存并重新同步 #

执行以下命令清理缓存，再重新同步项目：

./gradlew clean build --refresh-dependencies

内容的提问来源于stack exchange，提问作者Alexei