BAEL 2879 (#6767)

* BAEL-2727 Example Code

* Example code for BAEL-2879 Jackson YAML

jackson-2/src/test/java/com/baeldung/jackson/yaml/YamlUnitTest.java

@@ -0,0 +1,63 @@
+package com.baeldung.jackson.yaml;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+
+import java.io.File;
+import java.io.IOException;
+import java.math.BigDecimal;
+import java.math.RoundingMode;
+import java.time.LocalDate;
+import java.time.format.DateTimeFormatter;
+import java.util.ArrayList;
+import java.util.List;
+
+import org.junit.Before;
+import org.junit.Test;
+
+import com.baeldung.jackson.entities.Order;
+import com.baeldung.jackson.entities.OrderLine;
+import com.fasterxml.jackson.core.JsonGenerationException;
+import com.fasterxml.jackson.core.JsonParseException;
+import com.fasterxml.jackson.databind.JsonMappingException;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.databind.SerializationFeature;
+import com.fasterxml.jackson.dataformat.yaml.YAMLFactory;
+import com.fasterxml.jackson.dataformat.yaml.YAMLGenerator.Feature;
+
+public class YamlUnitTest {
+    private ObjectMapper mapper;
+
+    @Before
+    public void setup() {
+        mapper = new ObjectMapper(new YAMLFactory().disable(Feature.WRITE_DOC_START_MARKER));
+        mapper.findAndRegisterModules();
+        mapper.disable(SerializationFeature.WRITE_DATES_AS_TIMESTAMPS);
+    }
+
+    @Test
+    public void givenYamlInput_ObjectCreated() throws JsonParseException, JsonMappingException, IOException {
+        Order order = mapper.readValue(new File("src/main/resources/orderInput.yaml"), Order.class);
+        assertEquals("A001", order.getOrderNo());
+        assertEquals(LocalDate.parse("2019-04-17", DateTimeFormatter.ISO_DATE), order.getDate());
+        assertEquals("Customer, Joe", order.getCustomerName());
+        assertEquals(2, order.getOrderLines()
+            .size());
+    }
+
+    @Test
+    public void givenYamlObject_FileWritten() throws JsonGenerationException, JsonMappingException, IOException {
+        List<OrderLine> lines = new ArrayList<>();
+        lines.add(new OrderLine("Copper Wire (200ft)", 1, new BigDecimal(50.67).setScale(2, RoundingMode.HALF_UP)));
+        lines.add(new OrderLine("Washers (1/4\")", 24, new BigDecimal(.15).setScale(2, RoundingMode.HALF_UP)));
+        Order order = new Order(
+            "B-9910", 
+            LocalDate.parse("2019-04-18", DateTimeFormatter.ISO_DATE), 
+            "Customer, Jane", 
+            lines);
+        mapper.writeValue(new File("src/main/resources/orderOutput.yaml"), order);
+
+        File outputYaml = new File("src/main/resources/orderOutput.yaml");
+        assertTrue(outputYaml.exists());
+    }
+}