minSDK 버전이 낮지만 LocalDate 같은 걸 쓰는 방법이 있었다.
https://developer.android.com/studio/write/java8-support?hl=ko#library-desugaring
android { defaultConfig { // Required when setting minSdkVersion to 20 or lower multiDexEnabled true } compileOptions { // Flag to enable support for the new language APIs coreLibraryDesugaringEnabled true // Sets Java compatibility to Java 8 sourceCompatibility JavaVersion.VERSION_1_8 targetCompatibility JavaVersion.VERSION_1_8 } } dependencies { coreLibraryDesugaring 'com.android.tools:desugar_jdk_libs:1.1.5' }