Add all layers implementation.

demo-infrastructure/build.gradle.kts

@@ -0,0 +1,12 @@
+plugins {
+    kotlin("jvm")
+    id("io.spring.dependency-management") version "1.1.7"
+    id("java")
+}
+
+dependencies {
+    implementation(kotlin("stdlib"))
+    implementation(project(":demo-application"))
+    implementation(project(":demo-domain"))
+    implementation("org.springframework:spring-context")
+}

demo-infrastructure/src/main/kotlin/com/example/demo/infrastructure/product/ProductInMemoryAdapter.kt

@@ -0,0 +1,41 @@
+package com.example.demo.infrastructure.product
+
+import com.example.demo.domain.product.model.Product
+import com.example.demo.domain.product.model.ProductType.LIQUID
+import com.example.demo.domain.product.model.ProductType.SOLID
+import com.example.demo.domain.product.port.ProductPort
+import org.springframework.stereotype.Component
+import java.util.*
+
+@Component
+class ProductInMemoryAdapter : ProductPort {
+    private val products = mutableListOf(
+        Product(
+            id = UUID.randomUUID(),
+            name = "Banana x5",
+            type = SOLID
+        ),
+        Product(
+            id = UUID.randomUUID(),
+            name = "Banana juice 1L",
+            type = LIQUID
+        )
+    )
+
+    override fun getById(id: UUID): Product? = products.find { product -> product.id == id }
+
+    override fun getAll(): List<Product> = products
+
+    override fun save(product: Product) {
+        if (getById(product.id) == null) {
+            products.add(product)
+        } else {
+            deleteById(product.id)
+            save(product)
+        }
+    }
+
+    override fun deleteById(id: UUID) {
+        products.removeIf { product -> product.id == id }
+    }
+}