build.gradle.kts

/*
 * This file was generated by the Gradle 'init' task.
 *
 * This generated file contains a sample Java project to get you started.
 * For more details take a look at the Java Quickstart chapter in the Gradle
 * user guide available at https://docs.gradle.org/5.0/userguide/tutorial_java_projects.html
 */
import com.github.jengelman.gradle.plugins.shadow.tasks.ShadowJar

plugins {
    // Apply the java plugin to add support for Java
    id("java")

    // Apply the application plugin to add support for building an application
    id("application")
    id("com.github.johnrengelman.shadow") version "5.0.0"
}

repositories {
    // Use jcenter for resolving your dependencies.
    // You can declare any Maven/Ivy/file repository here.
    jcenter()
}

dependencies {
    implementation(fileTree(mapOf("dir" to "libs", "include" to arrayOf("*.jar"))))
    // This dependency is found on compile classpath of this component and consumers.
    implementation("com.google.guava:guava:26.0-jre")
    implementation("com.ibm.icu:icu4j:63.1")

    // Use JUnit test framework
    testImplementation("junit:junit:4.12")
}

application {
    // Define the main class for the application
    mainClassName = "App.KatakanaRomajiConvert"
}

tasks.withType<Jar> {
    manifest {
        attributes(mapOf(
                "Main-Class" to "App.KatakanaRomajiConvert"
        ))
    }
}

tasks.withType<ShadowJar> {
    baseName = "kana2romaji"
    classifier = ""
    version = ""
}

gradle.properties

org.gradle.jvmargs='-Dfile.encoding=UTF-8'
org.gradle.daemon=true
// org.gradle.java.home=C:\\JDKPortable
// systemProp.http.proxyHost=
// systemProp.http.proxyPort=
// systemProp.https.proxyHost=
// systemProp.https.proxyPort=

KatakanaRomajiConvert.java

package App;

import java.util.Optional;
import com.ibm.icu.text.Transliterator;

public class KatakanaRomajiConvert {

    public static void main(String[] args) {
        try {
            System.out.println(convertRomaji(args[0]));
        } catch (ArrayIndexOutOfBoundsException e) {
            System.out.println("");
        }
    }

    public static String convertRomaji() {
        return "";
    }
    public static String convertRomaji(String word) {
        Transliterator transliterator = Transliterator.getInstance("Katakana-Latin");
        Optional<String> wordOpt = Optional.ofNullable(word);
        String kana = wordOpt.orElse("");
        String result = transliterator.transliterate(kana);
        return result;
    }
}

KatakanaRomajiConvertTest.java

package App;

import org.junit.Test;
import static org.junit.Assert.*;

public class KatakanaRomajiConvertTest {
    @Test
    public void testKatakanaRomajiConvertNullArg() {
        KatakanaRomajiConvert AppTest = new KatakanaRomajiConvert();
        assertEquals("", AppTest.convertRomaji(null));
    }
    public void testKatakanaRomajiConvertNoArg() {
        KatakanaRomajiConvert AppTest = new KatakanaRomajiConvert();
        assertEquals("", AppTest.convertRomaji());
    }
    public void testKatakanaRomajiConvertEmptyArg() {
        KatakanaRomajiConvert AppTest = new KatakanaRomajiConvert();
        assertEquals("", AppTest.convertRomaji(""));
    }
    public void testKatakanaRomajiConvertAnArg() {
        KatakanaRomajiConvert AppTest = new KatakanaRomajiConvert();
        assertEquals("kyouto", AppTest.convertRomaji("キョウト"));
    }
    public void testKatakanaRomajiConvertMixCharsStringArg() {
        KatakanaRomajiConvert AppTest = new KatakanaRomajiConvert();
        assertEquals("あいうアイウabcＡＢＣ", AppTest.convertRomaji("あいうaiuabcＡＢＣ"));
    }
    public void testKatakanaRomajiConvertMixCharsAndSpcStringArg() {
        KatakanaRomajiConvert AppTest = new KatakanaRomajiConvert();
        assertEquals("あいう アイウ abc ＡＢＣ", AppTest.convertRomaji("あいうアイウabcＡＢＣ"));
    }
}