Chapter 10 을 공부하라

src/main/java/com/johngrib/objects/_02_movie/Money.java

@@ -4,9 +4,9 @@
 import lombok.ToString;
 
 import java.math.BigDecimal;
+import java.util.Objects;
 
 /** 금액. */
-@EqualsAndHashCode
 @ToString
 public class Money {
   public static final Money ZERO = Money.wons(0);
@@ -44,4 +44,21 @@ public boolean isLessThan(Money other) {
   public boolean isGreaterThanOrEqual(Money other) {
     return amount.compareTo(other.amount) >= 0;
   }
+
+  @Override
+  public boolean equals(Object o) {
+    if (this == o) {
+      return true;
+    }
+    if (o == null || getClass() != o.getClass()) {
+      return false;
+    }
+    Money money = (Money) o;
+    return amount.compareTo(money.amount) == 0;
+  }
+
+  @Override
+  public int hashCode() {
+    return Objects.hash(amount);
+  }
 }

src/main/java/com/johngrib/objects/_10_call/Call.java

@@ -0,0 +1,24 @@
+package com.johngrib.objects._10_call;
+
+import lombok.Getter;
+
+import java.time.Duration;
+import java.time.LocalDateTime;
+
+/**
+ * 개별 통화 시간.
+ */
+public class Call {
+  @Getter
+  private LocalDateTime from;
+  private LocalDateTime to;
+
+  public Call(LocalDateTime from, LocalDateTime to) {
+    this.from = from;
+    this.to = to;
+  }
+
+  public Duration getDuration() {
+    return Duration.between(from, to);
+  }
+}

src/main/java/com/johngrib/objects/_10_call/NightlyDiscountPhone.java

@@ -0,0 +1,38 @@
+package com.johngrib.objects._10_call;
+
+import com.johngrib.objects._02_movie.Money;
+
+import java.time.Duration;
+
+/**
+ * 심야 할인 요금제.
+ */
+public class NightlyDiscountPhone extends Phone {
+  private static final int LATE_NIGHT_HOUR = 22;
+
+  private Money nightlyAmount;
+  private Money regularAmount;
+  private Duration seconds;
+
+  public NightlyDiscountPhone(Money nightlyAmount, Money regularAmount, Duration seconds) {
+    super(0);
+    this.nightlyAmount = nightlyAmount;
+    this.regularAmount = regularAmount;
+    this.seconds = seconds;
+  }
+
+  public NightlyDiscountPhone(Money nightlyAmount, Money regularAmount, Duration seconds, double taxRate) {
+    super(taxRate);
+    this.nightlyAmount = nightlyAmount;
+    this.regularAmount = regularAmount;
+    this.seconds = seconds;
+  }
+
+  @Override
+  protected Money calculateCallFee(Call call) {
+    if (call.getFrom().getHour() >= LATE_NIGHT_HOUR) {
+      return nightlyAmount.times(call.getDuration().getSeconds() / seconds.getSeconds());
+    }
+    return regularAmount.times(call.getDuration().getSeconds() / seconds.getSeconds());
+  }
+}

src/main/java/com/johngrib/objects/_10_call/Phone.java

@@ -0,0 +1,30 @@
+package com.johngrib.objects._10_call;
+
+import com.johngrib.objects._02_movie.Money;
+import lombok.Getter;
+
+import java.util.ArrayList;
+import java.util.List;
+
+public abstract class Phone {
+
+  private double taxRate;
+  /** 전체 통화 목록 */
+  @Getter
+  private List<Call> calls = new ArrayList<>();
+
+  public Phone(double taxRate) {
+    this.taxRate = taxRate;
+  }
+
+  public Money calculateFee() {
+    Money result = Money.ZERO;
+
+    for (Call call : calls) {
+      result = result.plus(calculateCallFee(call));
+    }
+    return result.plus(result.times(taxRate));
+  }
+
+  abstract protected Money calculateCallFee(Call call);
+}

src/main/java/com/johngrib/objects/_10_call/RegularPhone.java

@@ -0,0 +1,34 @@
+package com.johngrib.objects._10_call;
+
+import com.johngrib.objects._02_movie.Money;
+import lombok.Getter;
+
+import java.time.Duration;
+
+/**
+ * 일반 요금제.
+ */
+public class RegularPhone extends Phone {
+  /** 단위 요금. */
+  @Getter
+  private Money amount;
+  @Getter
+  private Duration seconds;
+
+  public RegularPhone(Money amount, Duration seconds) {
+    super(0);
+    this.amount = amount;
+    this.seconds = seconds;
+  }
+
+  public RegularPhone(Money amount, Duration seconds, double taxRate) {
+    super(taxRate);
+    this.amount = amount;
+    this.seconds = seconds;
+  }
+
+  @Override
+  protected Money calculateCallFee(Call call) {
+    return amount.times(call.getDuration().getSeconds() / seconds.getSeconds());
+  }
+}

src/test/java/com/johngrib/objects/_10_call/PhoneTest.java

@@ -0,0 +1,45 @@
+package com.johngrib.objects._10_call;
+
+import com.johngrib.objects._02_movie.Money;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Nested;
+import org.junit.jupiter.api.Test;
+
+import java.time.Duration;
+import java.time.LocalDateTime;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+@DisplayName("Phone 클래스")
+class PhoneTest {
+  @Nested
+  @DisplayName("calculateCallFee 메소드")
+  class Describe_calculateCallFee {
+
+    @Nested
+    @DisplayName("10초에 5원씩 부과되는 요금제에 가입했고")
+    class Context_with_10sec_5won_phone {
+      RegularPhone givenPhone() {
+        return new RegularPhone(Money.wons(5), Duration.ofSeconds(10));
+      }
+
+      @Nested
+      @DisplayName("1분짜리 통화를 했다면")
+      class Context_with_1_min_call {
+
+        Call getFirstCall() {
+          return new Call(
+                  LocalDateTime.of(2018, 1, 1, 12, 10, 0),
+                  LocalDateTime.of(2018, 1, 1, 12, 11, 0)
+          );
+        }
+
+        @Test
+        @DisplayName("30원을 리턴한다")
+        void it_returns_calculated_won() {
+          assertEquals(givenPhone().calculateCallFee(getFirstCall()), Money.wons(30.0));
+        }
+      }
+    }
+  }
+}