변경된 파라미터 개수로 인해 객체로 변경 - #19

김정호/src/test/java/com/hou27/chap03/ExpiryDateCalculatorTest.java

@@ -12,17 +12,17 @@ public class ExpiryDateCalculatorTest {
     assertExpiryDate(LocalDate.of(2022, 3, 1), 10_000, LocalDate.of(2022, 4, 1));
   }
 
-  private void assertExpiryDate(LocalDate billingDate, int payAmount, LocalDate expiryDate) {
-    ExpiryDateCalculator cal = new ExpiryDateCalculator();
-    LocalDate result = cal.calculateExpiryDate(billingDate, payAmount);
-    assertEquals(expiryDate, result);
-  }
-
   @Test
   void 납부일과_한달_뒤_일자가_같지_않음() {
     assertExpiryDate(LocalDate.of(2019, 1, 31), 10_000, LocalDate.of(2019, 2, 28));
     assertExpiryDate(LocalDate.of(2019, 5, 31), 10_000, LocalDate.of(2019, 6, 30));
     assertExpiryDate(LocalDate.of(2020, 1, 31), 10_000, LocalDate.of(2020, 2, 29));
     assertExpiryDate(LocalDate.of(2020, 5, 31), 10_000, LocalDate.of(2020, 6, 30));
   }
+
+  private void assertExpiryDate(LocalDate billingDate, int payAmount, LocalDate expiryDate) {
+    ExpiryDateCalculator cal = new ExpiryDateCalculator();
+    LocalDate result = cal.calculateExpiryDate(billingDate, payAmount);
+    assertEquals(expiryDate, result);
+  }
 }

김정호/src/test/java/com/hou27/chap03/PayData.java

@@ -0,0 +1,46 @@
+package com.hou27.chap03;
+
+import java.time.LocalDate;
+
+public class PayData {
+  private LocalDate billingDate;
+  private int payAmount;
+
+  private PayData() {};
+
+  public PayData(LocalDate billingDate, int payAmount) {
+    this.billingDate = billingDate;
+    this.payAmount = payAmount;
+  }
+
+  public LocalDate getBillingDate() {
+    return billingDate;
+  }
+
+  public int getPayAmount() {
+    return payAmount;
+  }
+
+  /*
+   * billingDate와 payAmount를 설정하는 것을 쉽게 알 수 있도록
+   * builder pattern을 적용
+   */
+  public static class Builder {
+    private PayData data = new PayData();
+
+    public Builder billingDate(LocalDate billingDate) {
+      data.billingDate = billingDate;
+      return this;
+    }
+
+    public Builder payAmount(int payAmount) {
+      data.payAmount = payAmount;
+      return this;
+    }
+
+    public PayData build() {
+      return data;
+    }
+  }
+
+}