Builder Pattern (chaining)

design-pattern/src/Builder/Builder

@@ -1,3 +1,6 @@
 Builder Pattern
  - 복잡한 단계가 필요한 인스턴스 생성을 빌드 패턴을 통해서 구현
- - 복잡한 단계를 거쳐야 생성되는 객체의 구현을 서브 클래스에게 넘겨주는 패턴
+ - 복잡한 단계를 거쳐야 생성되는 객체의 구현을 서브 클래스에게 넘겨주는 패턴
+
+ - 많은 변수를 가진 객체의 생성을 가독성 높도록
+ - 많은 인자를 가진 객체 생성을 다른 객체의 도움으로 생성

design-pattern/src/Builder/Builder2/Computer.java

@@ -0,0 +1,43 @@
+package Builder.Builder2;
+
+public class Computer {
+
+    private String cpu;
+    private String ram;
+    private String storage;
+
+    @Override
+    public String toString() {
+        return cpu + ", " + ram + ", " + storage;
+    }
+
+    public Computer(String cpu, String ram, String storage) {
+        this.cpu = cpu;
+        this.ram = ram;
+        this.storage = storage;
+    }
+
+    public String getCpu() {
+        return cpu;
+    }
+
+    public void setCpu(String cpu) {
+        this.cpu = cpu;
+    }
+
+    public String getRam() {
+        return ram;
+    }
+
+    public void setRam(String ram) {
+        this.ram = ram;
+    }
+
+    public String getStorage() {
+        return storage;
+    }
+
+    public void setStorage(String storage) {
+        this.storage = storage;
+    }
+}

design-pattern/src/Builder/Builder2/ComputerBuilder.java

@@ -0,0 +1,36 @@
+package Builder.Builder2;
+
+public class ComputerBuilder {
+
+    private Computer computer;
+
+    private ComputerBuilder() {
+        computer = new Computer("default", "default", "default");
+    }
+
+    public static ComputerBuilder start() {
+        return new ComputerBuilder();
+    }
+    public static ComputerBuilder startWithCpu(String cpu) {
+        ComputerBuilder builder = new ComputerBuilder();
+        builder.computer.setCpu(cpu);
+        return builder;
+    }
+
+    public ComputerBuilder setCpu(String cpu) {
+        computer.setCpu(cpu);
+        return this;
+    }
+    public ComputerBuilder setRam(String ram) {
+        computer.setRam(ram);
+        return this;
+    }
+    public ComputerBuilder setStorage(String storage) {
+        computer.setStorage(storage);
+        return this;
+    }
+    public Computer build() {
+        return this.computer;
+    }
+
+}

design-pattern/src/Builder/Builder2/Main.java

@@ -0,0 +1,16 @@
+package Builder.Builder2;
+
+public class Main {
+
+    public static void main(String[] args) {
+        Computer computer = ComputerBuilder
+//                .start()
+//                .setCpu("i7")
+                .startWithCpu("i7")
+                .setRam("8g")
+                .setStorage("256g ssd")
+                .build();
+
+        System.out.println(computer.toString());
+    }
+}