BAEL-6647: How to handle character encoding in JSON POST Request (#14335)

Co-authored-by: Tapan Avasthi <tavasthi@Tapans-MacBook-Air.local>

spring-web-modules/spring-resttemplate-2/src/main/java/com/baeldung/resttemplate/RestTemplateApplication.java

@@ -0,0 +1,16 @@
+package com.baeldung.resttemplate;
+
+import java.util.Collections;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+
+@SpringBootApplication
+public class RestTemplateApplication {
+
+    public static void main(String[] args) {
+        SpringApplication app = new SpringApplication(RestTemplateApplication.class);
+        app.setDefaultProperties(Collections.singletonMap("server.servlet.encoding.charset", "ISO-8859-1"));
+        app.run(args);
+    }
+}

spring-web-modules/spring-resttemplate-2/src/test/java/com/baeldung/resttemplate/postjson/RestTemplatePostRequestEncodingLiveTest.java

@@ -0,0 +1,59 @@
+package com.baeldung.resttemplate.postjson;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotEquals;
+import static org.junit.Assert.assertNotNull;
+
+import org.json.JSONException;
+
+import org.junit.BeforeClass;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.http.HttpEntity;
+import org.springframework.http.HttpHeaders;
+import org.springframework.http.MediaType;
+import org.springframework.test.context.junit4.SpringRunner;
+import org.springframework.web.client.RestTemplate;
+
+import com.baeldung.resttemplate.RestTemplateApplication;
+import com.baeldung.resttemplate.web.dto.Person;
+
+@RunWith(SpringRunner.class)
+@SpringBootTest(classes = RestTemplateApplication.class)
+public class RestTemplatePostRequestEncodingLiveTest {
+    private static String createPersonUrl;
+    private static RestTemplate restTemplate;
+
+    @BeforeClass
+    public static void runBeforeAllTestMethods() throws JSONException {
+        createPersonUrl = "http://localhost:8080/spring-rest/createPerson";
+        restTemplate = new RestTemplate();
+    }
+
+    @Test
+    public void givenJapaneseNameInDataWithoutHeaderEncoding_whenDataIsPostedByPostForObject_thenSaveIncorrectly() {
+        Person japanese = new Person(100, "関連当");
+
+        HttpHeaders headers = new HttpHeaders();
+        headers.setContentType(MediaType.APPLICATION_JSON);
+        HttpEntity<Person> request = new HttpEntity<>(japanese, headers);
+
+        Person person = restTemplate.postForObject(createPersonUrl, request, Person.class);
+        assertNotNull(person);
+        assertNotEquals("関連当", person.getName());
+    }
+
+    @Test
+    public void givenJapaneseNameInDataWithHeaderEncoding_whenDataIsPostedByPostForObject_thenSaveCorrectly() {
+        Person japanese = new Person(100, "関連当");
+
+        HttpHeaders headers = new HttpHeaders();
+        headers.set("Content-type", "application/json;charset=UTF-8");
+        HttpEntity<Person> request = new HttpEntity<>(japanese, headers);
+
+        Person person = restTemplate.postForObject(createPersonUrl, request, Person.class);
+        assertNotNull(person);
+        assertEquals("関連当", person.getName());
+    }
+}