JAVA-30632 Upgrade spring-resttemplate module to Spring Boot 3 (#15713)

* JAVA-30632 upgrade Spring rest template module to Spring Boot 3

* JAVA-30632 fix broken tests

spring-web-modules/spring-resttemplate/src/main/java/com/baeldung/resttemplate/configuration/SpringConfig.java

@@ -7,7 +7,6 @@ import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.ComponentScan;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.context.annotation.DependsOn;
-import org.springframework.web.client.RestTemplate;
 
 @Configuration
 @EnableAutoConfiguration

spring-web-modules/spring-resttemplate/src/main/java/com/baeldung/resttemplate/web/handler/RestTemplateResponseErrorHandler.java

@@ -2,40 +2,32 @@ package com.baeldung.resttemplate.web.handler;
 
 import java.io.IOException;
 
-import com.baeldung.resttemplate.web.exception.NotFoundException;
 import org.springframework.http.HttpStatus;
 import org.springframework.http.client.ClientHttpResponse;
 import org.springframework.stereotype.Component;
 import org.springframework.web.client.HttpClientErrorException;
 import org.springframework.web.client.ResponseErrorHandler;
 
+import com.baeldung.resttemplate.web.exception.NotFoundException;
+
 @Component
-public class RestTemplateResponseErrorHandler
-    implements ResponseErrorHandler {
+public class RestTemplateResponseErrorHandler implements ResponseErrorHandler {
 
     @Override
-    public boolean hasError(ClientHttpResponse httpResponse)
-        throws IOException {
-
-        return (httpResponse
-          .getStatusCode()
-          .series() == HttpStatus.Series.CLIENT_ERROR || httpResponse
-          .getStatusCode()
-          .series() == HttpStatus.Series.SERVER_ERROR);
+    public boolean hasError(ClientHttpResponse httpResponse) throws IOException {
+        return httpResponse.getStatusCode()
+            .is5xxServerError() || httpResponse.getStatusCode()
+            .is4xxClientError();
     }
 
     @Override
-    public void handleError(ClientHttpResponse httpResponse)
-        throws IOException {
-
-        if (httpResponse
-          .getStatusCode()
-          .series() == HttpStatus.Series.SERVER_ERROR) {
+    public void handleError(ClientHttpResponse httpResponse) throws IOException {
+        if (httpResponse.getStatusCode()
+            .is5xxServerError()) {
             //Handle SERVER_ERROR
             throw new HttpClientErrorException(httpResponse.getStatusCode());
-        } else if (httpResponse
-          .getStatusCode()
-          .series() == HttpStatus.Series.CLIENT_ERROR) {
+        } else if (httpResponse.getStatusCode()
+            .is4xxClientError()) {
             //Handle CLIENT_ERROR
             if (httpResponse.getStatusCode() == HttpStatus.NOT_FOUND) {
                 throw new NotFoundException();

spring-web-modules/spring-resttemplate/src/main/java/com/baeldung/sampleapp/web/controller/MyFooController.java

@@ -4,7 +4,7 @@ import java.util.Collection;
 import java.util.HashMap;
 import java.util.Map;
 
-import javax.servlet.http.HttpServletResponse;
+import jakarta.servlet.http.HttpServletResponse;
 
 import org.springframework.http.HttpStatus;
 import org.springframework.stereotype.Controller;

spring-web-modules/spring-resttemplate/src/test/java/com/baeldung/mock/EmployeeServiceUnitTest.java

@@ -1,5 +1,7 @@
 package com.baeldung.mock;
 
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
 import org.junit.jupiter.api.Assertions;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
@@ -18,8 +20,6 @@ import com.baeldung.resttemplate.web.model.Employee;
 @ExtendWith(MockitoExtension.class) 
 public class EmployeeServiceUnitTest {
 
-    private static final Logger logger = LoggerFactory.getLogger(EmployeeServiceUnitTest.class);
-
     @Mock
     private RestTemplate restTemplate;
 
@@ -34,7 +34,6 @@ public class EmployeeServiceUnitTest {
 
         Employee employee = empService.getEmployee("E001");
 
-        Assertions.assertEquals(emp, employee);
+        assertEquals(emp, employee);
     }
-
 }

spring-web-modules/spring-resttemplate/src/test/java/com/baeldung/resttemplate/RestTemplateBasicLiveTest.java

@@ -1,6 +1,6 @@
 package com.baeldung.resttemplate;
 
-import static org.apache.commons.codec.binary.Base64.encodeBase64;
+import java.util.Base64;
 import static com.baeldung.client.Consts.APPLICATION_PORT;
 import static org.junit.jupiter.api.Assertions.fail;
 
@@ -32,7 +32,7 @@ import org.springframework.web.client.RestTemplate;
 
 import com.fasterxml.jackson.databind.JsonNode;
 import com.fasterxml.jackson.databind.ObjectMapper;
-import com.fasterxml.jackson.dataformat.xml.XmlMapper;
+import org.springframework.web.client.RestTemplate;
 import com.google.common.base.Charsets;
 
 // This test needs RestTemplateConfigurationApplication to be up and running
@@ -62,7 +62,7 @@ public class RestTemplateBasicLiveTest {
         final RestTemplate template = new RestTemplate();
         final ResponseEntity<String> response = template.getForEntity(fooResourceUrl + "/1", String.class);
 
-        final ObjectMapper mapper = new XmlMapper();
+        final ObjectMapper mapper = new ObjectMapper();
         final JsonNode root = mapper.readTree(response.getBody());
         final JsonNode name = root.path("name");
         Assertions.assertNotNull(name.asText());
@@ -243,7 +243,7 @@ public class RestTemplateBasicLiveTest {
 
     private String getBase64EncodedLogPass() {
         final String logPass = "user1:user1Pass";
-        final byte[] authHeaderBytes = encodeBase64(logPass.getBytes(Charsets.US_ASCII));
+        final byte[] authHeaderBytes = Base64.getEncoder().encode(logPass.getBytes(Charsets.US_ASCII));
         return new String(authHeaderBytes, Charsets.US_ASCII);
     }