Migrate :countries and :flag-assets to Kotlin

Add simple tests and instrumented tests
Add Dependencies file

Author: Anton Azaryan

build.gradle

@@ -1,12 +1,15 @@
 buildscript {
-    
+
     repositories {
         google()
         jcenter()
+        mavenCentral()
+        maven { url "https://jitpack.io" }
     }
 
     dependencies {
-        classpath 'com.android.tools.build:gradle:3.0.1'
+        classpath "com.android.tools.build:gradle:$Version.androidGradle"
+        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$Version.kotlin"
         classpath 'com.github.dcendents:android-maven-gradle-plugin:2.0'
     }
 }
@@ -15,6 +18,8 @@ allprojects {
     repositories {
         google()
         jcenter()
+        mavenCentral()
+        maven { url 'https://jitpack.io' }
     }
 }
 

buildSrc/build.gradle.kts

@@ -0,0 +1,3 @@
+plugins {
+    `kotlin-dsl`
+}

buildSrc/src/main/java/Dependencies.kt

@@ -0,0 +1,41 @@
+import org.gradle.api.JavaVersion
+
+object General {
+  val sourceCompatibility = JavaVersion.VERSION_1_8
+  val targetCompatibility = JavaVersion.VERSION_1_8
+
+  const val TestInstrumentationRunner = "androidx.test.runner.AndroidJUnitRunner"
+}
+
+object Version {
+
+  // project
+  const val minSdk = 21
+  const val targetSdk = 28
+  const val buildToolsVersion = "28.0.3"
+  const val compileSdkVersion = 28
+  const val androidGradle = "3.2.1"
+
+  // kotlin
+  const val kotlin = "1.2.71" // https://kotlinlang.org/
+
+  // serialization
+  const val jackson = "2.9.7" //https://github.com/FasterXML/jackson-core
+
+  // tests
+  const val jUnit = "4.12"
+  const val androidJUnit = "1.0.0"
+  const val androidTestRunner = "1.0.0-rc01"
+  const val espresso = "3.1.0-alpha4"
+}
+
+object Deps {
+  const val kotlinStdlib = "org.jetbrains.kotlin:kotlin-stdlib-jdk7:${Version.kotlin}"
+  const val jacksonCore = "com.fasterxml.jackson.core:jackson-core:${Version.jackson}"
+
+  // Tests
+  const val jUnit = "junit:junit:${Version.jUnit}"
+  const val androidJUnit = "androidx.test.ext:junit:${Version.androidJUnit}"
+  const val androidTestRunner = "androidx.test:runner:${Version.androidTestRunner}"
+  const val espressoCore = "androidx.test.espresso:espresso-core:${Version.espresso}"
+}

countries/build.gradle

@@ -1,21 +1,42 @@
-apply plugin: 'java-library'
+apply plugin: 'com.android.library'
+apply plugin: 'kotlin-android'
 apply plugin: 'maven'
 
 group = 'com.github.jetruby'
 
 dependencies {
-    implementation fileTree(dir: 'libs', include: ['*.jar'])
-    implementation "com.fasterxml.jackson.core:jackson-core:$rootProject.ext.jacksonCoreVersion"
+    implementation Deps.kotlinStdlib
+    implementation Deps.jacksonCore
+    testImplementation Deps.jUnit
 }
 
-task sourcesJar(type: Jar, dependsOn: classes) {
-    classifier = 'sources'
-    from sourceSets.main.allSource
-}
+android {
+    compileSdkVersion Version.compileSdkVersion
+    buildToolsVersion Version.buildToolsVersion
+
+    defaultConfig {
+        minSdkVersion Version.minSdk
+        targetSdkVersion Version.targetSdk
+
+        testInstrumentationRunner General.TestInstrumentationRunner
+    }
 
-artifacts {
-    archives sourcesJar
+    buildTypes {
+
+        release {
+            minifyEnabled false
+            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
+        }
+    }
+
+    compileOptions {
+        sourceCompatibility General.sourceCompatibility
+        targetCompatibility General.targetCompatibility
+    }
 }
 
-sourceCompatibility = "1.8"
-targetCompatibility = "1.8"
+// build a jar with source files
+task sourcesJar(type: Jar) {
+    from android.sourceSets.main.java.srcDirs
+    classifier = 'sources'
+}

countries/src/main/AndroidManifest.xml

@@ -0,0 +1 @@
+<manifest package="com.jetruby.common.countries"/>

countries/src/main/java/com/jetruby/common/countries/Countries.java

@@ -0,0 +1,81 @@
+package com.jetruby.common.countries
+
+import android.content.Context
+import com.fasterxml.jackson.core.JsonFactory
+import com.fasterxml.jackson.core.JsonParser
+import com.fasterxml.jackson.core.JsonToken
+import com.jetruby.common.countries.Country.Companion.EMPTY
+import java.io.IOException
+import java.io.InputStreamReader
+import java.util.Comparator
+
+
+data class Country(
+  var name: String = "",
+  var countryCode: String = "",
+  var phoneCode: String = ""
+) {
+
+  companion object {
+    val EMPTY = Country()
+    fun china() = Country("China", "CN", "86")
+    fun usa() = Country("United States", "US", "1")
+    fun comparator(): Comparator<Country> =
+      Comparator { c1, c2 -> c1.countryCode.compareTo(c2.countryCode) }
+  }
+
+}
+
+@Throws(IOException::class)
+fun countryList(context: Context): List<Country> = parseList(
+  JsonFactory().createParser(
+    InputStreamReader(context.resources.openRawResource(R.raw.countries))
+  )
+)
+
+/* INTERNAL */
+
+internal class MutableCountry {
+  var name: String = ""
+  var countryCode: String = ""
+  var phoneCode: String = ""
+}
+
+@Throws(IOException::class)
+internal fun parse(jsonParser: JsonParser): Country {
+  val instance = MutableCountry()
+  if (jsonParser.currentToken == null) {
+    jsonParser.nextToken()
+  }
+  if (jsonParser.currentToken != JsonToken.START_OBJECT) {
+    jsonParser.skipChildren()
+    return EMPTY
+  }
+  while (jsonParser.nextToken() != JsonToken.END_OBJECT) {
+    val fieldName = jsonParser.currentName
+    jsonParser.nextToken()
+    parseField(instance, fieldName, jsonParser)
+    jsonParser.skipChildren()
+  }
+  return Country(instance.name, instance.countryCode, instance.phoneCode)
+}
+
+@Throws(IOException::class)
+internal fun parseField(instance: MutableCountry, fieldName: String, jsonParser: JsonParser) {
+  when (fieldName) {
+    "country_code" -> instance.countryCode = jsonParser.getValueAsString(null)
+    "name" -> instance.name = jsonParser.getValueAsString(null)
+    "phone_code" -> instance.phoneCode = jsonParser.getValueAsString(null)
+  }
+}
+
+@Throws(IOException::class)
+internal fun parseList(jsonParser: JsonParser): List<Country> {
+  jsonParser.nextToken()
+  val list: MutableList<Country> = mutableListOf()
+  if (jsonParser.currentToken == JsonToken.START_ARRAY) {
+    while (jsonParser.nextToken() != JsonToken.END_ARRAY)
+      list.add(parse(jsonParser))
+  }
+  return list
+}