JAVA-1555: Update "Spring Boot multi-module" article (#9609)

* JAVA-1555: Modified parent's pom to include new module

* JAVA-1555: Added missing module parent-multi-module

spring-boot-modules/spring-boot-custom-starter/parent-multi-module/application/pom.xml

@@ -0,0 +1,36 @@
+<?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 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+    <groupId>com.baeldung.example</groupId>
+    <artifactId>application</artifactId>
+    <packaging>jar</packaging>
+
+    <parent>
+        <groupId>com.baeldung</groupId>
+        <artifactId>parent-boot-2</artifactId>
+        <version>0.0.1-SNAPSHOT</version>
+        <relativePath>../../../../parent-boot-2</relativePath>
+    </parent>
+
+    <dependencies>
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-web</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>com.baeldung.example</groupId>
+            <artifactId>library</artifactId>
+            <version>${project.version}</version>
+        </dependency>
+    </dependencies>
+
+    <build>
+        <plugins>
+            <plugin>
+                <groupId>org.springframework.boot</groupId>
+                <artifactId>spring-boot-maven-plugin</artifactId>
+            </plugin>
+        </plugins>
+    </build>
+</project>

spring-boot-modules/spring-boot-custom-starter/parent-multi-module/application/src/main/java/com/baeldung/application/EvenOddApplication.java

@@ -0,0 +1,30 @@
+package com.baeldung.application;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.RequestParam;
+import org.springframework.web.bind.annotation.RestController;
+
+import com.baeldung.library.service.EvenOddService;
+
+@SpringBootApplication(scanBasePackages = "com.baeldung")
+@RestController
+public class EvenOddApplication {
+ 
+    private EvenOddService evenOddService;
+    
+    public EvenOddApplication(EvenOddService evenOddService) {
+        this.evenOddService = evenOddService;
+    }
+ 
+    @GetMapping("/validate/")
+    public String isEvenOrOdd(
+      @RequestParam("number") Integer number) {
+        return evenOddService.isEvenOrOdd(number);
+    }
+ 
+    public static void main(String[] args) {
+        SpringApplication.run(EvenOddApplication.class, args);
+    }
+}

spring-boot-modules/spring-boot-custom-starter/parent-multi-module/library/pom.xml

@@ -0,0 +1,23 @@
+<?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 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+    <groupId>com.baeldung.example</groupId>
+    <artifactId>library</artifactId>
+    <packaging>jar</packaging>
+
+    <parent>
+        <groupId>com.baeldung</groupId>
+        <artifactId>parent-boot-2</artifactId>
+        <version>0.0.1-SNAPSHOT</version>
+        <relativePath>../../../../parent-boot-2</relativePath>
+    </parent>
+
+    <dependencies>
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter</artifactId>
+        </dependency>
+    </dependencies>
+
+</project>

spring-boot-modules/spring-boot-custom-starter/parent-multi-module/library/src/main/java/com/baeldung/library/service/EvenOddService.java

@@ -0,0 +1,11 @@
+package com.baeldung.library.service;
+
+import org.springframework.stereotype.Service;
+
+@Service
+public class EvenOddService {
+ 
+    public String isEvenOrOdd(Integer number) {
+        return number % 2 == 0 ? "Even" : "Odd";
+    }
+}

spring-boot-modules/spring-boot-custom-starter/parent-multi-module/pom.xml

@@ -0,0 +1,15 @@
+<?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 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+    <groupId>com.baeldung</groupId>
+    <artifactId>parent-multi-module</artifactId>
+    <version>0.0.1-SNAPSHOT</version>
+    <packaging>pom</packaging>
+
+    <modules>
+        <module>library</module>
+        <module>application</module>
+    </modules>
+
+</project>

spring-boot-modules/spring-boot-custom-starter/pom.xml

@@ -18,6 +18,7 @@
         <module>greeter-spring-boot-autoconfigure</module>
         <module>greeter-spring-boot-starter</module>
         <module>greeter-spring-boot-sample-app</module>
+        <module>parent-multi-module</module>
     </modules>
 
 </project>