Make Mail supplier as auto-config

* Fix all their Checkstyle violations
* Fix Checkstyle violations in the `spring-kafka-supplier`, too

supplier/spring-kafka-supplier/src/main/java/org/springframework/cloud/fn/supplier/kafka/KafkaSupplierConfiguration.java

@@ -126,7 +126,7 @@ RecordFilterStrategy<Object, Object> recordFilterStrategy(KafkaSupplierPropertie
 
 		StandardEvaluationContext evaluationContext = IntegrationContextUtils.getEvaluationContext(beanFactory);
 
-		return consumerRecord -> Boolean.TRUE.equals(
+		return (consumerRecord) -> Boolean.TRUE.equals(
 				kafkaSupplierProperties.getRecordFilter().getValue(evaluationContext, consumerRecord, Boolean.class));
 	}
 

supplier/spring-kafka-supplier/src/main/java/org/springframework/cloud/fn/supplier/kafka/package-info.java

@@ -0,0 +1,4 @@
+/**
+ * The Apache Kafka supplier auto-configuration support.
+ */
+package org.springframework.cloud.fn.supplier.kafka;

supplier/spring-mail-supplier/README.adoc

@@ -9,7 +9,7 @@ Users have to subscribe to this `Flux` and receive the data.
 
 ## Beans for injection
 
-You can import the `MailSupplierConfiguration` in the application and then inject the following bean.
+The `MailSupplierConfiguration` auto-configuration provides the following bean:
 
 `mailSupplier`
 

supplier/spring-mail-supplier/src/main/java/org/springframework/cloud/fn/supplier/mail/MailSupplierConfiguration.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2020-2022 the original author or authors.
+ * Copyright 2020-2024 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.
@@ -25,11 +25,11 @@
 import org.reactivestreams.Publisher;
 import reactor.core.publisher.Flux;
 
+import org.springframework.boot.autoconfigure.AutoConfiguration;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty;
 import org.springframework.boot.context.properties.EnableConfigurationProperties;
 import org.springframework.cloud.fn.common.config.ComponentCustomizer;
 import org.springframework.context.annotation.Bean;
-import org.springframework.context.annotation.Configuration;
 import org.springframework.integration.core.MessageSource;
 import org.springframework.integration.dsl.IntegrationFlow;
 import org.springframework.integration.dsl.MessageProducerSpec;
@@ -38,38 +38,38 @@
 import org.springframework.integration.endpoint.ReactiveMessageSourceProducer;
 import org.springframework.integration.mail.MailHeaders;
 import org.springframework.integration.mail.dsl.ImapIdleChannelAdapterSpec;
+import org.springframework.integration.mail.dsl.ImapMailInboundChannelAdapterSpec;
 import org.springframework.integration.mail.dsl.Mail;
 import org.springframework.integration.mail.dsl.MailInboundChannelAdapterSpec;
+import org.springframework.integration.mail.dsl.Pop3MailInboundChannelAdapterSpec;
 import org.springframework.integration.transformer.support.AbstractHeaderValueMessageProcessor;
 import org.springframework.integration.transformer.support.HeaderValueMessageProcessor;
 import org.springframework.lang.Nullable;
 import org.springframework.messaging.Message;
 
 /**
- * Mail supplier components.
+ * Mail supplier auto-configuration.
  *
- * @author Amol
  * @author Artem Bilan
  * @author Chris Schaefer
- * @author Soby Chacko
  * @author Corneil du Plessis
+ * @author Soby Chacko
  */
-@Configuration(proxyBeanMethods = false)
 @EnableConfigurationProperties(MailSupplierProperties.class)
+@AutoConfiguration
 public class MailSupplierConfiguration {
 
-	final private MailSupplierProperties properties;
+	private final MailSupplierProperties properties;
 
 	public MailSupplierConfiguration(MailSupplierProperties properties) {
 		this.properties = properties;
 	}
 
 	@Bean
 	public Publisher<Message<Object>> mailInboundFlow(MessageProducerSupport messageProducer) {
-
 		return IntegrationFlow.from(messageProducer)
 			.transform(Mail.toStringTransformer(this.properties.getCharset()))
-			.enrichHeaders(h -> h.defaultOverwrite(true)
+			.enrichHeaders((h) -> h.defaultOverwrite(true)
 				.header(MailHeaders.TO, arrayToListProcessor(MailHeaders.TO))
 				.header(MailHeaders.CC, arrayToListProcessor(MailHeaders.CC))
 				.header(MailHeaders.BCC, arrayToListProcessor(MailHeaders.BCC)))
@@ -81,7 +81,7 @@ public Supplier<Flux<Message<?>>> mailSupplier(Publisher<Message<Object>> messag
 		return () -> Flux.from(messagePublisher);
 	}
 
-	private HeaderValueMessageProcessor<?> arrayToListProcessor(final String header) {
+	private HeaderValueMessageProcessor<?> arrayToListProcessor(String header) {
 		return new AbstractHeaderValueMessageProcessor<List<String>>() {
 
 			@Override
@@ -103,7 +103,8 @@ public List<String> processMessage(Message<?> message) {
 			.userFlag(this.properties.getUserFlag())
 			.javaMailProperties(getJavaMailProperties(urlName))
 			.selectorExpression(this.properties.getExpression())
-			.shouldMarkMessagesAsRead(this.properties.isMarkAsRead());
+			.shouldMarkMessagesAsRead(this.properties.isMarkAsRead())
+			.autoStartup(false);
 
 		if (imapIdleChannelAdapterSpecCustomizer != null) {
 			imapIdleChannelAdapterSpecCustomizer.customize(imapIdleChannelAdapterSpec);
@@ -118,18 +119,11 @@ public List<String> processMessage(Message<?> message) {
 
 		MailInboundChannelAdapterSpec<?, ?> adapterSpec;
 		URLName urlName = this.properties.getUrl();
-		switch (urlName.getProtocol().toUpperCase()) {
-			case "IMAP":
-			case "IMAPS":
-				adapterSpec = getImapChannelAdapterSpec(urlName);
-				break;
-			case "POP3":
-			case "POP3S":
-				adapterSpec = getPop3ChannelAdapterSpec(urlName);
-				break;
-			default:
-				throw new IllegalArgumentException("Unsupported mail protocol: " + urlName.getProtocol());
-		}
+		adapterSpec = switch (urlName.getProtocol().toUpperCase()) {
+			case "IMAP", "IMAPS" -> getImapChannelAdapterSpec(urlName);
+			case "POP3", "POP3S" -> getPop3ChannelAdapterSpec(urlName);
+			default -> throw new IllegalArgumentException("Unsupported mail protocol: " + urlName.getProtocol());
+		};
 		adapterSpec.javaMailProperties(getJavaMailProperties(urlName))
 			.userFlag(this.properties.getUserFlag())
 			.selectorExpression(this.properties.getExpression())
@@ -145,56 +139,44 @@ public List<String> processMessage(Message<?> message) {
 	@Bean("mailChannelAdapter")
 	@ConditionalOnProperty(value = "mail.supplier.idle-imap", matchIfMissing = true, havingValue = "false")
 	MessageProducerSupport mailMessageProducer(MessageSource<?> mailMessageSource) {
-		return new ReactiveMessageSourceProducer(mailMessageSource);
+		ReactiveMessageSourceProducer reactiveMessageSourceProducer = new ReactiveMessageSourceProducer(
+				mailMessageSource);
+		reactiveMessageSourceProducer.setAutoStartup(false);
+		return reactiveMessageSourceProducer;
 	}
 
-	/**
-	 * Method to build Mail Channel Adapter for POP3.
-	 * @param urlName Mail source URL.
-	 * @return Mail Channel for POP3
-	 */
-	@SuppressWarnings("rawtypes")
-	private MailInboundChannelAdapterSpec getPop3ChannelAdapterSpec(URLName urlName) {
+	private Pop3MailInboundChannelAdapterSpec getPop3ChannelAdapterSpec(URLName urlName) {
 		return Mail.pop3InboundAdapter(urlName.toString());
 	}
 
-	/**
-	 * Method to build Mail Channel Adapter for IMAP.
-	 * @param urlName Mail source URL.
-	 * @return Mail Channel for IMAP
-	 */
-	@SuppressWarnings("rawtypes")
-	private MailInboundChannelAdapterSpec getImapChannelAdapterSpec(URLName urlName) {
+	private ImapMailInboundChannelAdapterSpec getImapChannelAdapterSpec(URLName urlName) {
 		return Mail.imapInboundAdapter(urlName.toString()).shouldMarkMessagesAsRead(this.properties.isMarkAsRead());
 	}
 
 	private Properties getJavaMailProperties(URLName urlName) {
 		Properties javaMailProperties = new Properties();
 
 		switch (urlName.getProtocol().toUpperCase()) {
-			case "IMAP":
+			case "IMAP" -> {
 				javaMailProperties.setProperty("mail.imap.socketFactory.class", "javax.net.SocketFactory");
 				javaMailProperties.setProperty("mail.imap.socketFactory.fallback", "false");
 				javaMailProperties.setProperty("mail.store.protocol", "imap");
-				break;
-
-			case "IMAPS":
+			}
+			case "IMAPS" -> {
 				javaMailProperties.setProperty("mail.imap.socketFactory.class", "javax.net.ssl.SSLSocketFactory");
 				javaMailProperties.setProperty("mail.imap.socketFactory.fallback", "false");
 				javaMailProperties.setProperty("mail.store.protocol", "imaps");
-				break;
-
-			case "POP3":
+			}
+			case "POP3" -> {
 				javaMailProperties.setProperty("mail.pop3.socketFactory.class", "javax.net.SocketFactory");
 				javaMailProperties.setProperty("mail.pop3.socketFactory.fallback", "false");
 				javaMailProperties.setProperty("mail.store.protocol", "pop3");
-				break;
-
-			case "POP3S":
+			}
+			case "POP3S" -> {
 				javaMailProperties.setProperty("mail.pop3.socketFactory.class", "javax.net.ssl.SSLSocketFactory");
 				javaMailProperties.setProperty("mail.pop3.socketFactory.fallback", "false");
 				javaMailProperties.setProperty("mail.store.protocol", "pop3s");
-				break;
+			}
 		}
 
 		javaMailProperties.putAll(this.properties.getJavaMailProperties());

supplier/spring-mail-supplier/src/main/java/org/springframework/cloud/fn/supplier/mail/MailSupplierProperties.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2020-2020 the original author or authors.
+ * Copyright 2020-2024 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.
@@ -26,7 +26,7 @@
 import org.springframework.validation.annotation.Validated;
 
 /**
- * Properties for the file supplier.
+ * Configuration properties for Mail supplier.
  *
  * @author Gary Russell
  * @author Artem Bilan
@@ -58,7 +58,7 @@ public class MailSupplierProperties {
 	private boolean idleImap = false;
 
 	/**
-	 * JavaMail properties as a new line delimited string of name-value pairs, e.g.
+	 * Java Mail properties as a new line delimited string of name-value pairs, e.g.
 	 * 'foo=bar\n baz=car'.
 	 */
 	private Properties javaMailProperties = new Properties();
@@ -78,89 +78,53 @@ public class MailSupplierProperties {
 	 */
 	private String userFlag = AbstractMailReceiver.DEFAULT_SI_USER_FLAG;
 
-	/**
-	 * @return the markAsRead
-	 */
 	public boolean isMarkAsRead() {
 		return this.markAsRead;
 	}
 
-	/**
-	 * @param markAsRead the markAsRead to set
-	 */
 	public void setMarkAsRead(boolean markAsRead) {
 		this.markAsRead = markAsRead;
 	}
 
-	/**
-	 * @return the delete
-	 */
 	public boolean isDelete() {
 		return this.delete;
 	}
 
-	/**
-	 * @param delete the delete to set
-	 */
 	public void setDelete(boolean delete) {
 		this.delete = delete;
 	}
 
-	/**
-	 * @return the idleImap
-	 */
 	public boolean isIdleImap() {
 		return this.idleImap;
 	}
 
-	/**
-	 * @param idleImap the idleImap to set
-	 */
 	public void setIdleImap(boolean idleImap) {
 		this.idleImap = idleImap;
 	}
 
-	/**
-	 * @return the javaMailProperties
-	 */
 	@NotNull
 	public Properties getJavaMailProperties() {
 		return this.javaMailProperties;
 	}
 
-	/**
-	 * @param javaMailProperties the javaMailProperties to set
-	 */
 	public void setJavaMailProperties(Properties javaMailProperties) {
 		this.javaMailProperties = javaMailProperties;
 	}
 
-	/**
-	 * @return the url
-	 */
 	@NotNull
 	public URLName getUrl() {
 		return this.url;
 	}
 
-	/**
-	 * @param url the url to set
-	 */
 	public void setUrl(URLName url) {
 		this.url = url;
 	}
 
-	/**
-	 * @return the expression
-	 */
 	@NotNull
 	public String getExpression() {
 		return this.expression;
 	}
 
-	/**
-	 * @param expression the expression to set
-	 */
 	public void setExpression(String expression) {
 		this.expression = expression;
 	}

supplier/spring-mail-supplier/src/main/java/org/springframework/cloud/fn/supplier/mail/package-info.java

@@ -0,0 +1,4 @@
+/**
+ * The MQTT supplier auto-configuration support.
+ */
+package org.springframework.cloud.fn.supplier.mail;

supplier/spring-mail-supplier/src/main/resources/META-INF/spring/org.springframework.boot.autoconfigure.AutoConfiguration.imports

@@ -0,0 +1 @@
+org.springframework.cloud.fn.supplier.mail.MailSupplierConfiguration

supplier/spring-mail-supplier/src/test/java/org/springframework/cloud/fn/supplier/mail/AbstractMailSupplierTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2020-2020 the original author or authors.
+ * Copyright 2020-2024 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.
@@ -23,6 +23,7 @@
 import com.icegreen.greenmail.util.GreenMailUtil;
 import com.icegreen.greenmail.util.ServerSetup;
 import com.icegreen.greenmail.util.ServerSetupTest;
+import org.junit.jupiter.api.AfterAll;
 import org.junit.jupiter.api.BeforeAll;
 import reactor.core.publisher.Flux;
 
@@ -35,8 +36,8 @@
 import org.springframework.test.context.DynamicPropertyRegistry;
 import org.springframework.test.context.DynamicPropertySource;
 
-@SpringBootTest(webEnvironment = SpringBootTest.WebEnvironment.NONE, properties = { "mail.supplier.mark-as-read=true",
-		"mail.supplier.delete=false", "mail.supplier.user-flag=testSIUserFlag",
+@SpringBootTest(properties = { "mail.supplier.mark-as-read=true", "mail.supplier.delete=false",
+		"mail.supplier.user-flag=testSIUserFlag",
 		"mail.supplier.java-mail-properties=mail.imap.socketFactory.fallback=true\\n mail.store.protocol=imap\\n mail.debug=true" })
 @DirtiesContext
 public abstract class AbstractMailSupplierTests {
@@ -70,6 +71,11 @@ public static void setup() {
 		mailServer.start();
 	}
 
+	@AfterAll
+	static void tearDown() {
+		mailServer.stop();
+	}
+
 	@DynamicPropertySource
 	static void mongoDbProperties(DynamicPropertyRegistry registry) {
 		registry.add("test.mail.server.imap.port", mailServer.getImap().getServerSetup()::getPort);