BAEL-8043 - Changes according to comments.

Author: Andrei Branza

apache-libraries-2/src/main/java/com/baeldung/avro/SerializationDeserializationLogic.java

@@ -1,6 +1,7 @@
 package com.baeldung.avro;
 
 import generated.avro.Car;
+
 import org.apache.avro.file.DataFileReader;
 import org.apache.avro.file.DataFileWriter;
 import org.apache.avro.io.DatumReader;
@@ -13,28 +14,26 @@
 
 public class SerializationDeserializationLogic {
 
-    static void serializeCar(Car car) {
+    static void serializeCar(Car car) throws IOException {
 
         DatumWriter<Car> userDatumWriter = new SpecificDatumWriter(Car.class);
 
         try (DataFileWriter<Car> dataFileWriter = new DataFileWriter(userDatumWriter)) {
             dataFileWriter.create(car.getSchema(), new File("cars.avro"));
             dataFileWriter.append(car);
         } catch (IOException e) {
-            e.printStackTrace();
+            throw e;
         }
     }
 
-    static Car deserializeCar() {
+    static Car deserializeCar() throws IOException {
 
-        Car resultCar = null;
         DatumReader<Car> userDatumReader = new SpecificDatumReader(Car.class);
 
-        try (DataFileReader<Car> dataFileReader = new DataFileReader(new File("cars.avro"), userDatumReader)){
+        try (DataFileReader<Car> dataFileReader = new DataFileReader(new File("cars.avro"), userDatumReader)) {
             return dataFileReader.next();
         } catch (Exception e) {
-            e.printStackTrace();
+            throw e;
         }
-        return resultCar;
     }
 }

apache-libraries-2/src/main/java/com/baeldung/avro/car.avsc

@@ -12,7 +12,8 @@
             "default": 4
         },
         {   "name": "color",
-            "type": "string"
+            "type": ["null", "string"],
+            "default": null
         }
     ]
 }

apache-libraries-2/src/test/java/com/baeldung/avro/AvroDefaultValuesUnitTest.java

@@ -1,22 +1,26 @@
 package com.baeldung.avro;
 
 import generated.avro.Car;
+
 import org.junit.jupiter.api.Test;
 
+import java.io.IOException;
+
 import static org.junit.jupiter.api.Assertions.*;
 
 public class AvroDefaultValuesUnitTest {
 
     @Test
-    public void givenCarJsonSchema_whenCarIsSerialized_thenCarIsSuccessfullyDeserialized() {
+    public void givenCarJsonSchema_whenCarIsSerialized_thenCarIsSuccessfullyDeserialized() throws IOException {
 
-        Car car = Car.newBuilder().setColor("blue").build();
+        Car car = Car.newBuilder()
+            .build();
 
         SerializationDeserializationLogic.serializeCar(car);
         Car deserializedCar = SerializationDeserializationLogic.deserializeCar();
 
         assertEquals("Dacia", deserializedCar.getBrand());
         assertEquals(4, deserializedCar.getNumberOfDoors());
-        assertEquals("blue", deserializedCar.getColor());
+        assertNull(deserializedCar.getColor());
     }
 }