[1] add maven and add tests

.gitignore

+HELP.md
+target/
+!.mvn/wrapper/maven-wrapper.jar
+!**/src/main/**/target/
+!**/src/test/**/target/
+
+### STS ###
+.apt_generated
+.classpath
+.factorypath
+.project
+.settings
+.springBeans
+.sts4-cache
+
+### IntelliJ IDEA ###
+.idea
+*.iws
+*.iml
+*.ipr
+
+### NetBeans ###
+/nbproject/private/
+/nbbuild/
+/dist/
+/nbdist/
+/.nb-gradle/
+build/
+!**/src/main/**/build/
+!**/src/test/**/build/
+
+### VS Code ###
+.vscode/

pom.xml

+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
+	<modelVersion>4.0.0</modelVersion>
+	<parent>
+		<groupId>org.springframework.boot</groupId>
+		<artifactId>spring-boot-starter-parent</artifactId>
+		<version>2.5.2</version>
+		<relativePath/> <!-- lookup parent from repository -->
+	</parent>
+	<groupId>de.thd</groupId>
+	<artifactId>jsonparser</artifactId>
+	<version>1.0.0-SNAPSHOT</version>
+	<name>jsonparser</name>
+	<description>Coding challenge for new hires</description>
+	<properties>
+		<java.version>11</java.version>
+	</properties>
+	<dependencies>
+<!--		TODO Add here dependency to your preferred JSON parser framework -->
+		<dependency>
+			<groupId>org.junit.jupiter</groupId>
+			<artifactId>junit-jupiter</artifactId>
+			<version>5.7.2</version>
+			<scope>test</scope>
+		</dependency>
+		<dependency>
+			<groupId>org.assertj</groupId>
+			<artifactId>assertj-core</artifactId>
+			<version>3.19.0</version>
+			<scope>test</scope>
+		</dependency>
+	</dependencies>
+
+	<build>
+		<plugins>
+			<plugin>
+				<groupId>org.apache.maven.plugins</groupId>
+				<artifactId>maven-jar-plugin</artifactId>
+				<version>3.2.0</version>
+			</plugin>
+		</plugins>
+	</build>
+
+</project>

src/main/java/de/thd/jsonparser/JsonparserApplication.java

+package de.thd.jsonparser;
+
+import java.util.Collections;
+import java.util.List;
+
+public class JsonparserApplication {
+
+	public JsonparserApplication(String jsonContent) {
+		// TODO
+	}
+
+	public String getLeadDisplayName() {
+		// TODO
+		return "TODO";
+	}
+
+	public List<String> getAllIssueTypeIdsWhereNameStartsWith(String prefix) {
+		// TODO
+		return Collections.singletonList("TODO");
+	}
+
+	public List<String> getComponents() {
+		// TODO
+		return null;
+	}
+
+}

src/test/java/de/thd/jsonparser/JsonparserApplicationTests.java

+package de.thd.jsonparser;
+
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+
+import java.io.IOException;
+import java.net.URISyntaxException;
+import java.net.URL;
+import java.nio.charset.StandardCharsets;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.List;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+class JsonparserApplicationTests {
+	JsonparserApplication sut; // service under test
+
+	@BeforeEach
+	void setup() throws IOException, URISyntaxException {
+		URL url = Thread.currentThread().getContextClassLoader().getResource("input.json");
+		final String content = Files.readString(Path.of(url.toURI()), StandardCharsets.UTF_8);
+		sut = new JsonparserApplication(content);
+	}
+
+	@Test
+	void testGetLeadDisplayName() {
+		String actual = sut.getLeadDisplayName();
+		assertThat(actual).isEqualTo("Max Mustermann");
+	}
+
+	@Test
+	void testGetAllIssueTypeIdsWhereNameStartsWith() {
+		List<String> actual = sut.getAllIssueTypeIdsWhereNameStartsWith("Vertrag");
+		assertThat(actual).contains("10807");
+		assertThat(actual.size()).isEqualTo(2);
+		assertThat(actual).contains("10808");
+	}
+
+	@Test
+	void noComponents() {
+		var actual = sut.getComponents();
+		assertThat(actual).isEmpty();
+	}
+
+}