Updated sample to support allowed properties list

resolves #144

transition-sample/pom.xml

@@ -6,7 +6,7 @@
 	<parent>
 		<groupId>org.springframework.boot</groupId>
 		<artifactId>spring-boot-starter-parent</artifactId>
-		<version>2.2.2.RELEASE</version>
+		<version>2.4.2</version>
 		<relativePath/> <!-- lookup parent from repository -->
 	</parent>
 	<groupId>io.spring</groupId>
@@ -27,6 +27,11 @@
 			<groupId>org.springframework.boot</groupId>
 			<artifactId>spring-boot-starter-data-jdbc</artifactId>
 		</dependency>
+                <dependency>
+                    <groupId>org.springframework.boot</groupId>
+                    <artifactId>spring-boot-configuration-processor</artifactId>
+                    <optional>true</optional>
+                </dependency>
 		<dependency>
 			<groupId>org.springframework.cloud</groupId>
 			<artifactId>spring-cloud-starter-task</artifactId>

transition-sample/src/main/resources/META-INF/spring-configuration-metadata-whitelist.properties

@@ -0,0 +1 @@
+configuration-properties.classes=io.spring.taskapp.configuration.TaskAppProperties

transition-sample/src/test/java/io/spring/taskapp/TaskappApplicationTests.java

@@ -16,25 +16,24 @@
 
 package io.spring.taskapp;
 
-import org.junit.Rule;
-import org.junit.Test;
+
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 
 import org.springframework.boot.SpringApplication;
-import org.springframework.boot.test.system.OutputCaptureRule;
+import org.springframework.boot.test.system.CapturedOutput;
+import org.springframework.boot.test.system.OutputCaptureExtension;
 
 import static org.assertj.core.api.Assertions.assertThat;
 
+@ExtendWith(OutputCaptureExtension.class)
 public class TaskappApplicationTests {
 
-	@Rule
-	public OutputCaptureRule outputCapture = new OutputCaptureRule();
-
 	@Test
-	public void contextLoads() {
+	public void contextLoads(CapturedOutput output) {
 		String[] args = {"--taskapp.exitMessage=FOO"};
 		SpringApplication.run(TaskappApplication.class, args);
-
-		String output = this.outputCapture.toString();
+		
 		assertThat(output).contains(" exitMessage='FOO', errorMessage='null'");
 	}