Resolve placeholders in @ConfigurationProperties prefix

spring-boot/src/main/java/org/springframework/boot/context/properties/ConfigurationPropertiesBindingPostProcessor.java

@@ -289,6 +289,7 @@ public class ConfigurationPropertiesBindingPostProcessor implements BeanPostProc
 			String targetName = (StringUtils.hasLength(annotation.value()) ? annotation
 					.value() : annotation.prefix());
 			if (StringUtils.hasLength(targetName)) {
+				targetName = this.environment.resolvePlaceholders(targetName);
 				factory.setTargetName(targetName);
 			}
 		}

spring-boot/src/test/java/org/springframework/boot/context/properties/ConfigurationPropertiesBindingPostProcessorTests.java

@@ -148,6 +148,16 @@ public class ConfigurationPropertiesBindingPostProcessorTests {
 				equalTo("foo"));
 	}
 
+	@Test
+	public void placeholderInPrefix() throws Exception {
+		this.context = new AnnotationConfigApplicationContext();
+		EnvironmentTestUtils.addEnvironment(this.context, "foo:spam", "spam.foo:bar");
+		this.context.register(PlaceholderPrefixConfiguration.class);
+		this.context.refresh();
+		assertThat(this.context.getBean(PlaceholderPrefixConfiguration.class).getFoo(),
+				equalTo("bar"));
+	}
+
 	@Test
 	public void placeholderResolutionWithCustomLocation() throws Exception {
 		this.context = new AnnotationConfigApplicationContext();
@@ -373,6 +383,22 @@ public class ConfigurationPropertiesBindingPostProcessorTests {
 
 	}
 
+	@EnableConfigurationProperties
+	@ConfigurationProperties(prefix = "${foo:bar}")
+	public static class PlaceholderPrefixConfiguration {
+
+		private String foo;
+
+		public String getFoo() {
+			return this.foo;
+		}
+
+		public void setFoo(String foo) {
+			this.foo = foo;
+		}
+
+	}
+
 	@EnableConfigurationProperties
 	@ConfigurationProperties(locations = "custom-location.yml")
 	public static class CustomConfigurationLocation {