done

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

         this.routingNumber = routingNumber;
         this.accountNumber = accountNumber;
     }
+
+    public Check(Long id, String payerName, String routingNumber, String accountNumber){
+        this.id = id;
+        this.payerName = payerName;
+        this.routingNumber = routingNumber;
+        this.accountNumber = accountNumber;
+    }
+
+
     public String getRoutingNumber() {
         return routingNumber;
     }
     }
 
     public String getShortDescription(){
-        String result = "Check " + getPayerName() + " ***" + lastFour(getAccountNumber());
+        String result = "Check " + getPayerName() + " ***" + lastFour(getAccountNumber()) + "\n";
         return result;
     }
 

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

     }
 
     public String getShortDescription(){
-        String result = "CC " + getPayerName() + " " + lastFour(getNumber()) + " " + getExpiredMonth() + "/" + getExpiredYear();
+        String result = "CC " + getPayerName() + " " + lastFour(getNumber()) + " " + getExpiredMonth() + "/" + getExpiredYear() + "\n";
         return result;
     }
 

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

         this.email = email;
     }
 
+    public PayPal(Long id, String payerName, String email){
+        this.id = id;
+        this.payerName = payerName;
+        this.email = email;
+    }
+
+
+
     public String getEmail() {
         return email;
     }
     }
 
     public String getShortDescription() {
-        String result = "Paypal " + getPayerName() + " " + getEmail();
+        String result = "Paypal " + getPayerName() + " " + getEmail() + "\n";
         return result;
     }
 

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

 package com.zipcoder.payment;
 
+import java.util.Arrays;
+
 public class PaymentPresenter {
 
+    public String toString(Payment[] payments){
+        Arrays.sort(payments, new PaymentSortDescription());
+        return createArrayString(payments);
+    }
+
+    public String toStringByPayerName(Payment[] payments){
+        Arrays.sort(payments, new PaymentSortPayer());
+        return createArrayString(payments);
+    }
+
+    public String toStringById(Payment[] payments){
+        Arrays.sort(payments, new PaymentSortID());
+        return createArrayString(payments);
+    }
+
+    private String createArrayString(Payment[] payments){
+        StringBuilder result = new StringBuilder();
+        for(Payment element: payments){
+            result.append(element.getShortDescription());
+        }
+        return result.toString();
+    }
+
 
 }

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

+package com.zipcoder.payment;
+import java.util.Comparator;
+
+public class PaymentSortDescription implements Comparator<Payment>{
+    public int compare(Payment o1, Payment o2) {
+        return o1.getShortDescription().compareTo(o2.getShortDescription());
+    }
+}

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

+package com.zipcoder.payment;
+
+import java.util.Comparator;
+
+public class PaymentSortID implements Comparator<Payment> {
+
+    public int compare(Payment o1, Payment o2) {
+        return o1.getId().compareTo(o2.getId());
+    }
+}

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

+package com.zipcoder.payment;
+
+import java.util.Comparator;
+
+public class PaymentSortPayer implements Comparator<Payment> {
+    public int compare(Payment o1, Payment o2) {
+        return o1.getPayerName().compareTo(o2.getPayerName());
+    }
+}

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

     public void getShortDescriptionTest(){
         Check test = new Check("Nafis", "123456789", "1234567890");
 
-        String expected = "Check Nafis ***7890";
+        String expected = "Check Nafis ***7890\n";
         String actual = test.getShortDescription();
         Assert.assertEquals(expected, actual);
     }

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

     public void getShortDescriptionTest(){
         CreditCard test = new CreditCard("Nafis", "1111222233331234", 9, 2018);
 
-        String expected = "CC Nafis 1234 9/2018";
+        String expected = "CC Nafis 1234 9/2018\n";
         String actual = test.getShortDescription();
         Assert.assertEquals(expected, actual);
     }
     public void constructorTest(){
         CreditCard test = new CreditCard("Nafis", "1111222233331234", 9, 2018);
 
-        String expected = "CC Nafis 1234 9/2018";
+        String expected = "CC Nafis 1234 9/2018\n";
         String actual = test.getShortDescription();
         Assert.assertEquals(expected, actual);
     }

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

     public void getShortDescriptionTest(){
         PayPal test = new PayPal("Nafis", "nafisnibir@gmail.com");
 
-        String expected = "Paypal Nafis nafisnibir@gmail.com";
+        String expected = "Paypal Nafis nafisnibir@gmail.com\n";
         String actual = test.getShortDescription();
         Assert.assertEquals(expected, actual);
     }
 
+    @Test
+    public void compareToTest(){
+        CreditCard test1 = new CreditCard("Nafis", "1111222233331234", 9, 2018);
+        PayPal test2 = new PayPal("Nafis", "nafisnibir@gmail.com");
+
+        Assert.assertTrue(test1.compareTo(test2) < 0);
+
+    }
+
 
 }

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

 package com.zipcoder.payment;
 
+import org.junit.Assert;
+import org.junit.Test;
+
 public class PaymentPresenterTest {
+
+    @Test
+    public void toStringTest1(){
+        Payment[] payments = new Payment[0];
+        PaymentPresenter presenter = new PaymentPresenter();
+        String expected = "";
+
+        String actual = presenter.toString(payments);
+
+        Assert.assertEquals(expected, actual);
+    }
+
+    @Test
+    public void toStringTest2(){
+        Payment[] payments = new Payment[2];
+        Payment paypal = new PayPal(4L, "Tia Mowry", "tia@mowry.com");
+        Payment check = new Check(81L, "Tia Mowry", "11432543", "134344551");
+
+        payments[0] = paypal;
+        payments[1] = check;
+
+        PaymentPresenter presenter = new PaymentPresenter();
+        String expected = "Check Tia Mowry ***4551\nPaypal Tia Mowry tia@mowry.com\n";
+
+        String actual = presenter.toString(payments);
+        Assert.assertEquals(expected, actual);
+    }
+
+    @Test
+    public void toStringTest3(){
+        Payment[] payments = new Payment[2];
+        Payment paypal = new PayPal(4L, "Tamara Mowry", "tamara@mowry.com");
+        Payment check = new Check(81L, "Tia Mowry", "11432543", "134344551");
+
+        payments[0] = paypal;
+        payments[1] = check;
+
+        PaymentPresenter presenter = new PaymentPresenter();
+        String expected = "Paypal Tamara Mowry tamara@mowry.com\nCheck Tia Mowry ***4551\n";
+
+        String actual = presenter.toStringByPayerName(payments);
+        Assert.assertEquals(expected, actual);
+    }
+
+    @Test
+    public void toString4(){
+        Payment[] payments = new Payment[2];
+        Payment paypal = new PayPal(81L, "Tamara Mowry", "tamara@mowry.com");
+        Payment check = new Check(120L, "Tia Mowry", "11432543", "134344551");
+
+        payments[0] = paypal;
+        payments[1] = check;
+
+        PaymentPresenter presenter = new PaymentPresenter();
+        String expected = "Paypal Tamara Mowry tamara@mowry.com\nCheck Tia Mowry ***4551\n";
+
+        String actual = presenter.toStringById(payments);
+        Assert.assertEquals(expected, actual);
+    }
+
+
+
 }

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

+package com.zipcoder.payment;
+
+import org.junit.Assert;
+import org.junit.Test;
+
+import static org.junit.Assert.*;
+
+public class PaymentSortPayerTest {
+
+    @Test
+    public void compareTest(){
+
+        PaymentSortPayer test = new PaymentSortPayer();
+
+        CreditCard test1 = new CreditCard("Nafis", "1111222233331234", 9, 2018);
+        PayPal test2 = new PayPal("Nafis", "nafisnibir@gmail.com");
+
+        Assert.assertTrue(test.compare(test1, test2) == 0);
+    }
+
+    @Test
+    public void compareTest1(){
+
+        PaymentSortPayer test = new PaymentSortPayer();
+
+        CreditCard test1 = new CreditCard("Nafis", "1111222233331234", 9, 2018);
+        PayPal test2 = new PayPal("Afis", "nafisnibir@gmail.com");
+
+        Assert.assertTrue(test.compare(test1, test2) > 0);
+    }
+
+    @Test
+    public void compareTest2(){
+
+        PaymentSortPayer test = new PaymentSortPayer();
+
+        CreditCard test1 = new CreditCard("Nafis", "1111222233331234", 9, 2018);
+        PayPal test2 = new PayPal("Zafis", "nafisnibir@gmail.com");
+
+        Assert.assertTrue(test.compare(test1, test2) < 0);
+    }
+}