id 1764056185

CMakeLists.txt

@@ -110,6 +110,7 @@ set(APP_SOURCES
     "src/patterns/behavioral/Observer.cpp"
     "src/patterns/creational/Singleton.cpp"
     "src/patterns/creational/FactoryMethod.cpp"
+    "src/patterns/creational/Builder.cpp"
 )
 
 # Test files

src/patterns/creational/Builder.cpp

@@ -0,0 +1,213 @@
+// cppcheck-suppress-file [functionStatic]
+
+// Builder is a creational design pattern that lets you construct complex objects step by step.
+// The pattern allows you to produce different types and representations of an object using the same construction code.
+// Appicability:
+// (*)  Use the Builder pattern to get rid of a “telescoping constructor”.
+// (**) when you want your code to be able to create different representations of some product (for example, stone and wooden houses).
+
+// UML: docs/uml/patterns_behavioral_iterator.drawio.svg
+
+#include <iostream>
+
+#include <iostream>
+#include <string>
+#include <vector>
+#include <memory>
+
+namespace
+{
+    namespace BuilderPattern
+    {
+        class Product
+        {
+        private:
+            std::vector<std::string> m_parts;
+
+        public:
+            void addPart(const std::string &part)
+            {
+                m_parts.push_back(part);
+            }
+
+            void print() const
+            {
+                std::cout << "Product parts: ";
+                for (size_t i = 0; i < m_parts.size(); ++i)
+                {
+                    std::cout << m_parts[i];
+                    if (i + 1 < m_parts.size())
+                        std::cout << ", ";
+                }
+                std::cout << "\n\n";
+            }
+        };
+
+        /**
+         * The Builder interface specifies methods for creating the different parts of
+         * the Product objects.
+         */
+        class IBuilder
+        {
+        public:
+            virtual ~IBuilder() = default;
+            virtual IBuilder &reset() = 0;
+            virtual IBuilder &producePart1() = 0;
+            virtual IBuilder &producePart2() = 0;
+            virtual IBuilder &producePart3() = 0;
+
+            virtual Product *const build() = 0;
+        };
+
+        class AbstractBuilder : public IBuilder
+        {
+        protected:
+            Product *m_product;
+
+        public:
+            explicit AbstractBuilder()
+            {
+                m_product = new Product();
+            }
+
+            ~AbstractBuilder()
+            {
+                delete m_product;
+            }
+
+            AbstractBuilder(const AbstractBuilder &other)
+            {
+                if (m_product != nullptr)
+                {
+                    delete m_product;
+                }
+                m_product = new Product();
+                *m_product = *other.m_product;
+            }
+
+            AbstractBuilder &operator=(const AbstractBuilder &other)
+            {
+                if (this == &other)
+                {
+                    return *this;
+                }
+                if (m_product != nullptr)
+                {
+                    delete m_product;
+                }
+                m_product = new Product();
+                *m_product = *other.m_product;
+                return *this;
+            }
+
+            IBuilder &reset() override final
+            {
+                if (m_product != nullptr)
+                {
+                    delete m_product;
+                }
+                m_product = new Product();
+
+                return *this;
+            }
+        };
+
+        /**
+         * The Concrete Builder classes follow the Builder interface and provide
+         * specific implementations of the building steps. Your program may have several
+         * variations of Builders, implemented differently.
+         */
+        class SimpleBuilder : public AbstractBuilder
+        {
+        public:
+            IBuilder &producePart1() override
+            {
+                m_product->addPart("PART1");
+                return *this;
+            }
+
+            IBuilder &producePart2() override
+            {
+                m_product->addPart("PART2");
+                return *this;
+            }
+
+            IBuilder &producePart3() override
+            {
+                m_product->addPart("PART3");
+                return *this;
+            }
+
+            Product *const build() override
+            {
+                return m_product;
+            }
+        };
+
+        class ComplexBuilder : public AbstractBuilder
+        {
+        public:
+            IBuilder &producePart1() override
+            {
+                m_product->addPart("PART_1-X9a7Fq!2@Lm#48Z");
+                return *this;
+            }
+
+            IBuilder &producePart2() override
+            {
+                m_product->addPart("PART_2-X9a7Fq!2@Lm#48Z");
+                return *this;
+            }
+
+            IBuilder &producePart3() override
+            {
+                m_product->addPart("PART_3-X9a7Fq!2@Lm#48Z");
+                return *this;
+            }
+
+            Product *const build() override
+            {
+                return m_product;
+            }
+        };
+
+        namespace Client
+        {
+            void clientCode(IBuilder *const builder)
+            {
+                const Product *product1 = (*builder).producePart1().producePart2().producePart3().build();
+                product1->print();
+
+                const Product *product2 = (*builder).reset().producePart1().build();
+                product2->print();
+            }
+        }
+
+        void run()
+        {
+            {
+                std::cout << "ConcreteBuilder: Simple\n";
+                IBuilder *builder = new SimpleBuilder();
+                Client::clientCode(builder);
+                delete builder;
+            }
+            {
+                std::cout << "ConcreteBuilder: Complex\n";
+                IBuilder *builder = new ComplexBuilder();
+                Client::clientCode(builder);
+                delete builder;
+            }
+        }
+    }
+}
+
+struct BuilderAutoRunner
+{
+    BuilderAutoRunner()
+    {
+        std::cout << "\n--- Builder Pattern Example ---\n";
+        BuilderPattern::run();
+    }
+};
+
+static BuilderAutoRunner instance;