Test Serialize/Deserialize Optional with Jackson

2017-02-05 18:21:52 +00:00
parent 5218116a80
commit ec2bfa7014
3 changed files with 109 additions and 4 deletions
@@ -0,0 +1,74 @@
+package com.baeldung.jackson.miscellaneous.mixin;
+
+import com.fasterxml.jackson.core.JsonProcessingException;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.datatype.jdk8.Jdk8Module;
+import static io.restassured.path.json.JsonPath.from;
+import java.io.IOException;
+import java.util.Optional;
+import static org.assertj.core.api.Assertions.assertThat;
+import org.junit.Test;
+
+public class OptionalTypeTest {
+
+    ObjectMapper mapper = new ObjectMapper()
+            .registerModule(new Jdk8Module());
+
+    @Test
+    public void givenOptional_whenSerializing_thenValueInJson() throws JsonProcessingException {
+
+        // arrange
+        String subTitle = "The Parish Boy's Progress";
+        Book book = new Book();
+        book.setTitle("Oliver Twist");
+        book.setSubTitle(Optional.of(subTitle));
+
+        // act
+        String result = mapper.writeValueAsString(book);
+
+        // assert
+        assertThat(from(result).getString("subTitle")).isEqualTo(subTitle);
+    }
+
+    @Test
+    public void givenEmptyOptional_whenSerializing_thenNullValue() throws JsonProcessingException {
+
+        // arrange
+        Book book = new Book();
+        book.setTitle("Oliver Twist");
+        book.setSubTitle(Optional.empty());
+
+        // act
+        String result = mapper.writeValueAsString(book);
+
+        // assert
+        assertThat(from(result).getString("subTitle")).isNull();
+    }
+
+    @Test
+    public void givenField_whenDeserializing_thenOptionalWithValue() throws IOException {
+
+        // arrange
+        String subTitle = "The Parish Boy's Progress";
+        String book = "{ \"title\": \"Oliver Twist\", \"subTitle\": \"" + subTitle + "\" }";
+
+        // act
+        Book result = mapper.readValue(book, Book.class);
+
+        // assert
+        assertThat(result.getSubTitle()).isEqualTo(Optional.of(subTitle));
+    }
+
+    @Test
+    public void givenEmptyField_whenDeserializing_thenEmptyOptional() throws IOException {
+
+        // arrange
+        String book = "{ \"title\": \"Oliver Twist\", \"subTitle\": null }";
+
+        // act
+        Book result = mapper.readValue(book, Book.class);
+
+        // assert
+        assertThat(result.getSubTitle()).isEmpty();
+    }
+}