通常gradle項目在gradle\wrapper\gradle-wrapper.properties中配置在線gradle：
distributionBase=GRADLE_USER_HOME
distributionPath=wrapper/dists
zipStoreBase=GRADLE_USER_HOME
zipStorePath=wrapper/dists
distributionUrl=https\://services.gradle.org/distributions/gradle-4.2.1-all.zip
把它更寫成：
distributionUrl=file:///E:/gradle421/gradle-4.2.1-all.zip