Extract constant for 'vcap' property source name

The string "vcap" was used multiple times when creating a
PropertiesPropertySource. Extracting it into a named constant improves
readability and helps clarify the purpose of the value.

- Follows the pattern used for other well-known property source names
- Helps future maintainers understand the intent of the property source

Signed-off-by: wonyongg <[email protected]>

Author: wonyongg

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/cloud/CloudFoundryVcapEnvironmentPostProcessor.java

@@ -95,6 +95,8 @@ public class CloudFoundryVcapEnvironmentPostProcessor implements EnvironmentPost
 
 	private static final String VCAP_SERVICES = "VCAP_SERVICES";
 
+	private static final String VCAP_PROPERTY_SOURCE_NAME = "vcap";
+
 	private final Log logger;
 
 	// Before ConfigDataEnvironmentPostProcessor so values there can use these
@@ -126,12 +128,12 @@ public void postProcessEnvironment(ConfigurableEnvironment environment, SpringAp
 			addWithPrefix(properties, getPropertiesFromApplication(environment, jsonParser), "vcap.application.");
 			addWithPrefix(properties, getPropertiesFromServices(environment, jsonParser), "vcap.services.");
 			MutablePropertySources propertySources = environment.getPropertySources();
+			PropertiesPropertySource vcapSource = new PropertiesPropertySource(VCAP_PROPERTY_SOURCE_NAME, properties);
 			if (propertySources.contains(CommandLinePropertySource.COMMAND_LINE_PROPERTY_SOURCE_NAME)) {
-				propertySources.addAfter(CommandLinePropertySource.COMMAND_LINE_PROPERTY_SOURCE_NAME,
-						new PropertiesPropertySource("vcap", properties));
+				propertySources.addAfter(CommandLinePropertySource.COMMAND_LINE_PROPERTY_SOURCE_NAME, vcapSource);
 			}
 			else {
-				propertySources.addFirst(new PropertiesPropertySource("vcap", properties));
+				propertySources.addFirst(vcapSource);
 			}
 		}
 	}