P02: Maven multi-module skeleton — domain, application, adapter-persistence, adapter-web, bootstrap

shopforge-application/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 https://maven.apache.org/xsd/maven-4.0.0.xsd">
+  <modelVersion>4.0.0</modelVersion>
+  <parent><groupId>dev.shopforge</groupId><artifactId>shopforge</artifactId><version>0.1.0-SNAPSHOT</version></parent>
+  <artifactId>shopforge-application</artifactId>
+  <name>ShopForge :: application</name>
+
+  <dependencies>
+    <dependency><groupId>dev.shopforge</groupId><artifactId>shopforge-domain</artifactId></dependency>
+    <!-- sirf spring-context — DI ke liye. Web nahi, JPA nahi. -->
+    <dependency><groupId>org.springframework</groupId><artifactId>spring-context</artifactId></dependency>
+  </dependencies>
+</project>

shopforge-application/src/main/java/dev/shopforge/application/ShopNotFound.java

@@ -0,0 +1,7 @@
+package dev.shopforge.application;
+
+public class ShopNotFound extends RuntimeException {
+    public ShopNotFound(String subdomain) {
+        super("Is subdomain ki koi shop nahi mili: " + subdomain);
+    }
+}

shopforge-application/src/main/java/dev/shopforge/application/ShopService.java

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+package dev.shopforge.application;
+
+import dev.shopforge.domain.Shop;
+import dev.shopforge.domain.ShopRepository;
+import org.springframework.stereotype.Service;
+
+/** Use case. Domain ka port maangta hai — JPA ka naam tak nahi jaanta. */
+@Service
+public class ShopService {
+
+    private final ShopRepository shops;
+
+    public ShopService(ShopRepository shops) {   // constructor injection — Java Doc 22
+        this.shops = shops;
+    }
+
+    public Shop bySubdomain(String subdomain) {
+        return shops.bySubdomain(subdomain)
+                .orElseThrow(() -> new ShopNotFound(subdomain));
+    }
+}