Support IPv6 addresses in spring.rabbitmq.addresses

Refine parsing logic in `RabbitProperties` so that IPv6 addresses can
be used.

Fixes gh-28133

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/amqp/RabbitProperties.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2020 the original author or authors.
+ * Copyright 2012-2021 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -1083,7 +1083,7 @@ public class RabbitProperties {
 		}
 
 		private void parseHostAndPort(String input, boolean sslEnabled) {
-			int portIndex = input.indexOf(':');
+			int portIndex = input.lastIndexOf(':');
 			if (portIndex == -1) {
 				this.host = input;
 				this.port = (determineSslEnabled(sslEnabled)) ? DEFAULT_PORT_SECURE : DEFAULT_PORT;

spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/amqp/RabbitPropertiesTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2020 the original author or authors.
+ * Copyright 2012-2021 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -240,6 +240,13 @@ class RabbitPropertiesTests {
 				.isEqualTo("user:secret@rabbit1.example.com:1234/alpha,rabbit2.example.com");
 	}
 
+	@Test
+	void ipv6Address() {
+		this.properties.setAddresses("amqp://foo:bar@[aaaa:bbbb:cccc::d]:5672");
+		assertThat(this.properties.determineHost()).isEqualTo("[aaaa:bbbb:cccc::d]");
+		assertThat(this.properties.determinePort()).isEqualTo(5672);
+	}
+
 	@Test
 	void determineAddressesReturnsAddressesWithJustHostAndPort() {
 		this.properties.setAddresses("user:secret@rabbit1.example.com:1234/alpha,rabbit2.example.com");