compareto

src/main/java/com/zipcoder/payment/Check.java

@@ -53,4 +53,8 @@ public class Check implements Payment {
     public String getShortDescription() {
         return "Check " + payerName + " ***" + getLastFourDigits(accountNumber);
     }
+
+    public int compareTo(Payment payment2) {
+        return this.getShortDescription().compareTo(payment2.getShortDescription());
+    }
 }

src/main/java/com/zipcoder/payment/CreditCard.java

@@ -43,4 +43,8 @@ public class CreditCard implements Payment {
     public String getShortDescription() {
         return "CC " + payerName + " " + getLastFourDigits(number) + " " + expiredMonth + "/" + expiredYear;
     }
+
+    public int compareTo(Payment payment2) {
+        return this.getShortDescription().compareTo(payment2.getShortDescription());
+    }
 }

src/main/java/com/zipcoder/payment/PayPal.java

@@ -1,6 +1,6 @@
 package com.zipcoder.payment;
 
-public class PayPal {
+public class PayPal implements Payment{
     long id;
     String payerName;
     String email;
@@ -34,4 +34,12 @@ public class PayPal {
     public void setEmail(String email) {
         this.email = email;
     }
+
+    public String getShortDescription() {
+        return "PayPal " + payerName + " " +email;
+    }
+
+    public int compareTo(Payment payment2) {
+        return this.getShortDescription().compareTo(payment2.getShortDescription());
+    }
 }

src/main/java/com/zipcoder/payment/Payment.java

@@ -1,6 +1,6 @@
 package com.zipcoder.payment;
 
-public interface Payment {
+public interface Payment extends Comparable<Payment>{
 
     public long getId();
 

src/main/java/com/zipcoder/payment/PaymentSortByPayer.java

@@ -0,0 +1,4 @@
+package com.zipcoder.payment;
+
+public class PaymentSortByPayer {
+}

src/test/java/com/zipcoder/payment/CheckTest.java

@@ -6,10 +6,12 @@ import org.junit.Test;
 
 public class CheckTest {
     Check testCheck;
+    CreditCard otherPayment;
 
     @Before
     public void initialize() {
         testCheck = new Check(100, "Karen Paige", "124567", "7654321");
+        otherPayment = new CreditCard(10, "John Hurt", "0043783590454335", 03,2020);
     }
 
     @Test
@@ -70,4 +72,11 @@ public class CheckTest {
 
         Assert.assertEquals(expected, actual);
     }
+
+    @Test
+    public void compareToTest() {
+        int actual = testCheck.compareTo(otherPayment);
+
+        Assert.assertTrue(actual > 0);
+    }
 }

src/test/java/com/zipcoder/payment/CreditCardTest.java

@@ -7,11 +7,14 @@ import org.junit.Test;
 
 public class CreditCardTest {
     CreditCard testCard;
+    PayPal otherPayment;
+    Check otherPayment2;
 
 
     @Before
     public void initialize() {
         testCard = new CreditCard(10, "John Hurt", "0043783590454335", 03,2020);
+        otherPayment =new PayPal(15,"Momo Hashimoto", "kawaii54@line.com");
 
     }
 
@@ -85,4 +88,12 @@ public class CreditCardTest {
 
         Assert.assertEquals(expected, actual);
     }
+
+    @Test
+    public void compareToTest() {
+        int actual = testCard.compareTo(otherPayment);
+
+        Assert.assertTrue(actual < 0);
+
+    }
 }

src/test/java/com/zipcoder/payment/PayPalTest.java

@@ -6,11 +6,13 @@ import org.junit.Test;
 
 public class PayPalTest {
     PayPal testPal;
+    Check otherPayment;
 
 
     @Before
     public void initialization() {
         testPal = new PayPal(15,"Momo Hashimoto", "kawaii54@line.com");
+        otherPayment = new Check(100, "Karen Paige", "124567", "7654321");
 
     }
     @Test
@@ -42,4 +44,20 @@ public class PayPalTest {
 
         Assert.assertEquals(expected, actual);
     }
+
+    @Test
+    public void getShortDescriptionTest() {
+        String expected = "PayPal Momo Hashimoto kawaii54@line.com";
+        String actual = testPal.getShortDescription();
+
+        Assert.assertEquals(expected, actual);
+    }
+
+    @Test
+    public void compareToTest() {
+        int actual = testPal.compareTo(otherPayment);
+
+
+        Assert.assertTrue(actual > 0);
+    }
 }