feature: upgrade Spring Boot 2.0.2 -> 4.1.1 (Java 17) incrementally

pom.xml

@@ -5,24 +5,27 @@
 
     <groupId>org.springframework</groupId>
     <artifactId>gs-spring-boot</artifactId>
-    <packaging>pom</packaging>
+    <packaging>jar</packaging>
     <version>0.1.0</version>
 
     <parent>
         <groupId>org.springframework.boot</groupId>
         <artifactId>spring-boot-starter-parent</artifactId>
-        <version>2.0.2.RELEASE</version>
+        <version>4.1.1</version>
     </parent>
 
     <dependencies>
         <dependency>
             <groupId>org.springframework.boot</groupId>
-            <artifactId>spring-boot-properties-migrator</artifactId>
-            <scope>runtime</scope>
+            <artifactId>spring-boot-starter-actuator</artifactId>
         </dependency>
         <dependency>
             <groupId>org.springframework.boot</groupId>
-            <artifactId>spring-boot-starter-web</artifactId>
+            <artifactId>spring-boot-starter-webmvc</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-restclient</artifactId>
         </dependency>
         <dependency>
             <groupId>org.springframework.boot</groupId>
@@ -35,7 +38,7 @@
     </dependencies>
 
     <properties>
-        <java.version>1.8</java.version>
+        <java.version>17</java.version>
     </properties>
 
 

src/main/java/hello/Application.java

@@ -12,17 +12,20 @@
 import org.springframework.boot.CommandLineRunner;
 import org.springframework.boot.SpringApplication;
 import org.springframework.boot.autoconfigure.SpringBootApplication;
-import org.springframework.boot.web.client.RestTemplateBuilder;
+import org.springframework.boot.restclient.RestTemplateBuilder;
 import org.springframework.context.ApplicationContext;
 import org.springframework.context.annotation.Bean;
 import org.springframework.jdbc.core.JdbcTemplate;
+import org.springframework.web.client.RestClientException;
 import org.springframework.web.client.RestTemplate;
 
 @SpringBootApplication
 public class Application implements CommandLineRunner {
 
     private static final Logger log = LoggerFactory.getLogger(Application.class);
 
+    private static final String QUOTE_URL = "http://gturnquist-quoters.cfapps.io/api/random";
+
     public static void main(String[] args) {
 
         ApplicationContext ctx = SpringApplication.run(Application.class, args);
@@ -35,9 +38,16 @@ public static void main(String[] args) {
             System.out.println(beanName);
         }
 
-        RestTemplate restTemplate =  new RestTemplate();
-        Quote quote = restTemplate.getForObject("http://gturnquist-quoters.cfapps.io/api/random", Quote.class);
-        log.info(quote.toString());
+        logRandomQuote(new RestTemplate());
+    }
+
+    private static void logRandomQuote(RestTemplate restTemplate) {
+        try {
+            Quote quote = restTemplate.getForObject(QUOTE_URL, Quote.class);
+            log.info(String.valueOf(quote));
+        } catch (RestClientException e) {
+            log.warn("Could not fetch random quote from {}: {}", QUOTE_URL, e.getMessage());
+        }
     }
 
 
@@ -48,11 +58,7 @@ public RestTemplate restTemplate(RestTemplateBuilder builder) {
 
     @Bean
     public CommandLineRunner run(RestTemplate restTemplate) throws Exception {
-        return args -> {
-            Quote quote = restTemplate.getForObject(
-                    "http://gturnquist-quoters.cfapps.io/api/random", Quote.class);
-            log.info(quote.toString());
-        };
+        return args -> logRandomQuote(restTemplate);
     }
 
 
@@ -80,8 +86,9 @@ public void run(String... args) throws Exception {
 
         log.info("Querying for customer records where first_name = 'Josh':");
         jdbcTemplate.query(
-                "SELECT id, first_name, last_name FROM customers WHERE first_name = ?", new Object[]{"Josh"},
-                (rs, rowNum) -> new Customer(rs.getLong("id"), rs.getString("first_name"), rs.getString("last_name"))
+                "SELECT id, first_name, last_name FROM customers WHERE first_name = ?",
+                (rs, rowNum) -> new Customer(rs.getLong("id"), rs.getString("first_name"), rs.getString("last_name")),
+                "Josh"
         ).forEach(customer -> log.info(customer.toString()));
 
     }