DSL: Mail Inbound Adapters

Add POP3 Server for Tests

Polishing; PR Comments; IMAP4 Server

spring-integration-java-dsl/build.gradle

@@ -94,6 +94,8 @@ dependencies {
 	}
 	testRuntime "com.sun.mail:mailapi:$mailVersion"
 	testRuntime "com.sun.mail:smtp:$mailVersion"
+	testRuntime "com.sun.mail:pop3:$mailVersion"
+	testRuntime "com.sun.mail:imap:$mailVersion"
 
 	jacoco "org.jacoco:org.jacoco.agent:$jacocoVersion:runtime"
 }

spring-integration-java-dsl/src/main/java/org/springframework/integration/dsl/mail/ImapMailInboundChannelAdapterSpec.java

@@ -0,0 +1,46 @@
+/*
+ * Copyright 2014 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.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.springframework.integration.dsl.mail;
+
+import org.springframework.integration.mail.ImapMailReceiver;
+import org.springframework.integration.mail.SearchTermStrategy;
+
+/**
+ * @author Gary Russell
+ *
+ */
+public class ImapMailInboundChannelAdapterSpec
+		extends MailInboundChannelAdapterSpec<ImapMailInboundChannelAdapterSpec, ImapMailReceiver> {
+
+	ImapMailInboundChannelAdapterSpec() {
+		this.receiver = new ImapMailReceiver();
+	}
+
+	ImapMailInboundChannelAdapterSpec(String url) {
+		this.receiver = new ImapMailReceiver(url);
+	}
+
+	public ImapMailInboundChannelAdapterSpec searchTermStrategy(SearchTermStrategy searchTermStrategy) {
+		this.receiver.setSearchTermStrategy(searchTermStrategy);
+		return this;
+	}
+
+	public ImapMailInboundChannelAdapterSpec shouldMarkMessagesAsRead(boolean shouldMarkMessagesAsRead) {
+		this.receiver.setShouldMarkMessagesAsRead(shouldMarkMessagesAsRead);
+		return this;
+	}
+
+}

spring-integration-java-dsl/src/main/java/org/springframework/integration/dsl/mail/Mail.java

@@ -25,4 +25,25 @@ public class Mail {
 		return new MailSendingMessageHandlerSpec(host);
 	}
 
+	public static Pop3MailInboundChannelAdapterSpec pop3InboundAdapter() {
+		return new Pop3MailInboundChannelAdapterSpec();
+	}
+
+	public static Pop3MailInboundChannelAdapterSpec pop3InboundAdapter(String url) {
+		return new Pop3MailInboundChannelAdapterSpec(url);
+	}
+
+	public static Pop3MailInboundChannelAdapterSpec pop3InboundAdapter(String host, int port, String username,
+			String password) {
+		return new Pop3MailInboundChannelAdapterSpec(host, port, username, password);
+	}
+
+	public static ImapMailInboundChannelAdapterSpec imapInboundAdapter() {
+		return new ImapMailInboundChannelAdapterSpec();
+	}
+
+	public static ImapMailInboundChannelAdapterSpec imapInboundAdapter(String url) {
+		return new ImapMailInboundChannelAdapterSpec(url);
+	}
+
 }

spring-integration-java-dsl/src/main/java/org/springframework/integration/dsl/mail/MailInboundChannelAdapterSpec.java

@@ -0,0 +1,80 @@
+/*
+ * Copyright 2014 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.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.springframework.integration.dsl.mail;
+
+import java.util.Properties;
+
+import javax.mail.Authenticator;
+import javax.mail.Session;
+
+import org.springframework.integration.dsl.core.MessageSourceSpec;
+import org.springframework.integration.dsl.support.PropertiesBuilder;
+import org.springframework.integration.dsl.support.PropertiesConfigurer;
+import org.springframework.integration.mail.AbstractMailReceiver;
+import org.springframework.integration.mail.MailReceivingMessageSource;
+
+/**
+ * @author Gary Russell
+ *
+ */
+public abstract class MailInboundChannelAdapterSpec<S extends MailInboundChannelAdapterSpec<S, R>,
+		R extends AbstractMailReceiver>
+		extends MessageSourceSpec<S, MailReceivingMessageSource> {
+
+	protected volatile R receiver;
+
+	public S selectorExpression(String selectorExpression) {
+		this.receiver.setSelectorExpression(PARSER.parseExpression(selectorExpression));
+		return _this();
+	}
+
+	public S session(Session session) {
+		this.receiver.setSession(session);
+		return _this();
+	}
+
+	public S javaMailProperties(Properties javaMailProperties) {
+		this.receiver.setJavaMailProperties(javaMailProperties);
+		return _this();
+	}
+
+	public S javaMailProperties(PropertiesConfigurer configurer) {
+		PropertiesBuilder properties = new PropertiesBuilder();
+		configurer.configure(properties);
+		return javaMailProperties(properties.get());
+	}
+
+	public S javaMailAuthenticator(Authenticator javaMailAuthenticator) {
+		this.receiver.setJavaMailAuthenticator(javaMailAuthenticator);
+		return _this();
+	}
+
+	public S maxFetchSize(int maxFetchSize) {
+		this.receiver.setMaxFetchSize(maxFetchSize);
+		return _this();
+	}
+
+	public S shouldDeleteMessages(boolean shouldDeleteMessages) {
+		this.receiver.setShouldDeleteMessages(shouldDeleteMessages);
+		return _this();
+	}
+
+	@Override
+	public MailReceivingMessageSource doGet() {
+		return new MailReceivingMessageSource(this.receiver);
+	}
+
+}

spring-integration-java-dsl/src/main/java/org/springframework/integration/dsl/mail/MailSendingMessageHandlerSpec.java

@@ -29,8 +29,8 @@ import org.springframework.mail.javamail.JavaMailSenderImpl;
  * @author Gary Russell
  * @author Artem Bilan
  */
-public class MailSendingMessageHandlerSpec extends
-		MessageHandlerSpec<MailSendingMessageHandlerSpec, MailSendingMessageHandler> {
+public class MailSendingMessageHandlerSpec
+		extends MessageHandlerSpec<MailSendingMessageHandlerSpec, MailSendingMessageHandler> {
 
 	private final JavaMailSenderImpl sender = new JavaMailSenderImpl();
 

spring-integration-java-dsl/src/main/java/org/springframework/integration/dsl/mail/Pop3MailInboundChannelAdapterSpec.java

@@ -0,0 +1,43 @@
+/*
+ * Copyright 2014 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.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.springframework.integration.dsl.mail;
+
+import org.springframework.integration.mail.Pop3MailReceiver;
+
+/**
+ * @author Gary Russell
+ *
+ */
+public class Pop3MailInboundChannelAdapterSpec
+		extends MailInboundChannelAdapterSpec<Pop3MailInboundChannelAdapterSpec, Pop3MailReceiver> {
+
+	Pop3MailInboundChannelAdapterSpec() {
+		this.receiver = new Pop3MailReceiver();
+	}
+
+	Pop3MailInboundChannelAdapterSpec(String url) {
+		this.receiver = new Pop3MailReceiver(url);
+	}
+
+	Pop3MailInboundChannelAdapterSpec(String host, String username, String password) {
+		this.receiver = new Pop3MailReceiver(host, username, password);
+	}
+
+	Pop3MailInboundChannelAdapterSpec(String host, int port, String username, String password) {
+		this.receiver = new Pop3MailReceiver(host, port, username, password);
+	}
+
+}

spring-integration-java-dsl/src/test/java/org/springframework/integration/dsl/test/mail/MailTests.java

@@ -18,11 +18,15 @@ package org.springframework.integration.dsl.test.mail;
 import static org.hamcrest.Matchers.containsString;
 import static org.hamcrest.Matchers.endsWith;
 import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotNull;
 import static org.junit.Assert.assertThat;
 import static org.junit.Assert.assertTrue;
 
 import java.util.Properties;
 
+import javax.mail.internet.MimeMessage;
+import javax.mail.internet.MimeMessage.RecipientType;
+
 import org.junit.AfterClass;
 import org.junit.BeforeClass;
 import org.junit.Test;
@@ -35,13 +39,19 @@ import org.springframework.context.annotation.Configuration;
 import org.springframework.integration.config.EnableIntegration;
 import org.springframework.integration.dsl.IntegrationFlow;
 import org.springframework.integration.dsl.IntegrationFlows;
+import org.springframework.integration.dsl.channel.MessageChannels;
 import org.springframework.integration.dsl.mail.Mail;
+import org.springframework.integration.dsl.support.Pollers;
+import org.springframework.integration.dsl.test.mail.PoorMansMailServer.ImapServer;
+import org.springframework.integration.dsl.test.mail.PoorMansMailServer.Pop3Server;
 import org.springframework.integration.dsl.test.mail.PoorMansMailServer.SmtpServer;
 import org.springframework.integration.mail.MailHeaders;
 import org.springframework.integration.support.MessageBuilder;
 import org.springframework.integration.test.util.TestUtils;
+import org.springframework.messaging.Message;
 import org.springframework.messaging.MessageChannel;
 import org.springframework.messaging.MessageHandler;
+import org.springframework.messaging.PollableChannel;
 import org.springframework.test.annotation.DirtiesContext;
 import org.springframework.test.context.ContextConfiguration;
 import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
@@ -56,15 +66,23 @@ import org.springframework.util.SocketUtils;
 @DirtiesContext
 public class MailTests {
 
-	private final static int port = SocketUtils.findAvailableTcpPort();
+	private final static int smtpPort = SocketUtils.findAvailableTcpPort();
 
-	private static SmtpServer server = PoorMansMailServer.smtp(port);
+	private static SmtpServer smtpServer = PoorMansMailServer.smtp(smtpPort);
+
+	private final static int pop3Port = SocketUtils.findAvailableTcpPort(smtpPort + 1);
+
+	private static Pop3Server pop3Server = PoorMansMailServer.pop3(pop3Port);
+
+	private final static int imapPort = SocketUtils.findAvailableTcpPort(pop3Port + 1);
+
+	private static ImapServer imapServer = PoorMansMailServer.imap(imapPort);
 
 
 	@BeforeClass
 	public static void setup() throws InterruptedException {
 		int n = 0;
-		while (n++ < 100 && !server.isListening()) {
+		while (n++ < 100 && (!smtpServer.isListening() || !pop3Server.isListening() || !imapServer.isListening())) {
 			Thread.sleep(100);
 		}
 		assertTrue(n < 100);
@@ -72,17 +90,24 @@ public class MailTests {
 
 	@AfterClass
 	public static void tearDown() {
-		server.stop();
+		smtpServer.stop();
+		pop3Server.stop();
+		imapServer.stop();
 	}
 
 	@Autowired
-	@Qualifier("sendMailChannel")
 	private MessageChannel sendMailChannel;
 
 	@Autowired
 	@Qualifier("sendMailEndpoint.handler")
 	private MessageHandler sendMailHandler;
 
+	@Autowired
+	private PollableChannel pop3Channel;
+
+	@Autowired
+	private PollableChannel imapChannel;
+
 	@Test
 	public void testOutbound() throws Exception {
 		assertEquals("localhost", TestUtils.getPropertyValue(this.sendMailHandler, "mailSender.host"));
@@ -98,12 +123,12 @@ public class MailTests {
 				.build());
 
 		int n = 0;
-		while (n++ < 100 && server.getMessages().size() == 0) {
+		while (n++ < 100 && smtpServer.getMessages().size() == 0) {
 			Thread.sleep(100);
 		}
 
-		assertTrue(server.getMessages().size() > 0);
-		String message = server.getMessages().get(0);
+		assertTrue(smtpServer.getMessages().size() > 0);
+		String message = smtpServer.getMessages().get(0);
 		assertThat(message, endsWith("foo\n"));
 		assertThat(message, containsString("foo@bar"));
 		assertThat(message, containsString("bar@baz"));
@@ -112,6 +137,28 @@ public class MailTests {
 
 	}
 
+	@Test
+	public void testPop3() throws Exception {
+		Message<?> message = this.pop3Channel.receive(10000);
+		assertNotNull(message);
+		MimeMessage mm = (MimeMessage) message.getPayload();
+		assertEquals("foo@bar", mm.getRecipients(RecipientType.TO)[0].toString());
+		assertEquals("bar@baz", mm.getFrom()[0].toString());
+		assertEquals("Test Email", mm.getSubject());
+		assertEquals("foo\r\n", mm.getContent());
+	}
+
+	@Test
+	public void testImap() throws Exception {
+		Message<?> message = this.imapChannel.receive(10000);
+		assertNotNull(message);
+		MimeMessage mm = (MimeMessage) message.getPayload();
+		assertEquals("foo@bar", mm.getRecipients(RecipientType.TO)[0].toString());
+		assertEquals("bar@baz", mm.getFrom()[0].toString());
+		assertEquals("Test Email", mm.getSubject());
+		assertEquals("foo\r\n", mm.getContent());
+	}
+
 	@Configuration
 	@EnableIntegration
 	public static class ContextConfiguration {
@@ -120,7 +167,7 @@ public class MailTests {
 		public IntegrationFlow sendMailFlow() {
 			return IntegrationFlows.from("sendMailChannel")
 					.handle(Mail.outboundAdapter("localhost")
-									.port(port)
+									.port(smtpPort)
 									.credentials("user", "pw")
 									.protocol("smtp")
 									.javaMailProperties(p -> p.put("mail.debug", "true")),
@@ -128,6 +175,28 @@ public class MailTests {
 					.get();
 		}
 
+		@Bean
+		public IntegrationFlow pop3MailFlow() {
+			return IntegrationFlows
+					.from(Mail.pop3InboundAdapter("localhost", pop3Port, "user", "pw")
+									.javaMailProperties(p -> p.put("mail.debug", "true")),
+							e -> e.autoStartup(true)
+									.poller(Pollers.fixedDelay(1000)))
+					.channel(MessageChannels.queue("pop3Channel"))
+					.get();
+		}
+
+		@Bean
+		public IntegrationFlow imapMailFlow() {
+			return IntegrationFlows
+					.from(Mail.imapInboundAdapter("imap://user:pw@localhost:" + imapPort + "/INBOX")
+									.javaMailProperties(p -> p.put("mail.debug", "true")),
+							e -> e.autoStartup(true)
+									.poller(Pollers.fixedDelay(1000)))
+					.channel(MessageChannels.queue("imapChannel"))
+					.get();
+		}
+
 	}
 
 }

spring-integration-java-dsl/src/test/java/org/springframework/integration/dsl/test/mail/PoorMansMailServer.java

@@ -46,69 +46,44 @@ public class PoorMansMailServer {
 		}
 	}
 
-	public static class SmtpServer implements Runnable {
+	public static Pop3Server pop3(int port) {
+		try {
+			return new Pop3Server(port);
+		}
+		catch (IOException e) {
+			throw new RuntimeException(e);
+		}
+	}
 
-		private final ServerSocket socket;
+	public static ImapServer imap(int port) {
+		try {
+			return new ImapServer(port);
+		}
+		catch (IOException e) {
+			throw new RuntimeException(e);
+		}
+	}
 
-		private final ExecutorService exec = Executors.newCachedThreadPool();
-
-		private final List<String> messages = new ArrayList<String>();
-
-		private volatile boolean listening;
+	public static class SmtpServer extends MailServer {
 
 		public SmtpServer(int port) throws IOException {
-			this.socket = ServerSocketFactory.getDefault().createServerSocket(port);
-			this.listening = true;
-			exec.execute(this);
-		}
-
-		public boolean isListening() {
-			return listening;
-		}
-
-		public List<String> getMessages() {
-			return messages;
+			super(port);
 		}
 
 		@Override
-		public void run() {
-			try {
-				while (!socket.isClosed()) {
-					Socket socket = this.socket.accept();
-					exec.execute(new SmtpHandler(socket));
-				}
-			}
-			catch (IOException e) {
-				this.listening = false;
-			}
+		protected MailHandler mailHandler(Socket socket) {
+			return new SmtpHandler(socket);
 		}
 
-		public void stop() {
-			try {
-				this.socket.close();
-			}
-			catch (IOException e) {
-				e.printStackTrace();
-			}
-			this.exec.shutdownNow();
-		}
-
-		public class SmtpHandler implements Runnable {
-
-			private final Socket socket;
-
-			private BufferedWriter writer;
+		public class SmtpHandler extends MailHandler {
 
 			public SmtpHandler(Socket socket) {
-				this.socket = socket;
+				super(socket);
 			}
 
 			@Override
-			public void run() {
+			void doRun() {
 				try {
-					StringBuilder sb = new StringBuilder();
-					BufferedReader reader = new BufferedReader(new InputStreamReader(this.socket.getInputStream()));
-					this.writer = new BufferedWriter(new OutputStreamWriter(this.socket.getOutputStream()));
 					write("220 foo SMTP");
 					while (!socket.isClosed()) {
 						String line = reader.readLine();
@@ -160,12 +135,253 @@ public class PoorMansMailServer {
 				}
 			}
 
-			private void write(String str) throws IOException {
+		}
+
+	}
+
+	public static class Pop3Server extends MailServer {
+
+		public Pop3Server(int port) throws IOException {
+			super(port);
+		}
+
+		@Override
+		protected MailHandler mailHandler(Socket socket) {
+			return new Pop3Handler(socket);
+		}
+
+		public class Pop3Handler extends MailHandler {
+
+			public Pop3Handler(Socket socket) {
+				super(socket);
+			}
+
+			@Override
+			void doRun() {
+				try {
+					write("+OK POP3");
+					while (!socket.isClosed()) {
+						String line = reader.readLine();
+						switch (line) {
+							case "CAPA":
+								write("+OK");
+								write("USER");
+								write(".");
+								break;
+							case "USER user":
+								write("+OK");
+								break;
+							case "PASS pw":
+								write("+OK");
+								break;
+							case "STAT":
+								write("+OK 1 3");
+								break;
+							case "NOOP":
+								write("+OK");
+								break;
+							case "RETR 1":
+								write("+OK");
+								write(MESSAGE);
+								write(".");
+								break;
+							case "QUIT":
+								write("+OK");
+								socket.close();
+								break;
+						}
+					}
+				}
+				catch (IOException e) {
+					e.printStackTrace();
+				}
+			}
+
+		}
+
+	}
+
+	public static class ImapServer extends MailServer {
+
+		public ImapServer(int port) throws IOException {
+			super(port);
+		}
+
+		@Override
+		protected MailHandler mailHandler(Socket socket) {
+			return new Pop3Handler(socket);
+		}
+
+		public class Pop3Handler extends MailHandler {
+
+			public Pop3Handler(Socket socket) {
+				super(socket);
+			}
+
+			@Override
+			void doRun() {
+				try {
+					write("* OK IMAP4rev1 Service Ready");
+					while (!socket.isClosed()) {
+						String line = reader.readLine();
+						if (line == null) {
+							break;
+						}
+						String tag = line.substring(0, line.indexOf(" ") + 1);
+						System.out.println(line);
+						if (line.endsWith("CAPABILITY")) {
+							write("* CAPABILITY IMAP4rev1");
+							write(tag + "OK CAPABILITY completed");
+						}
+						else if (line.endsWith("LOGIN user pw")) {
+							write(tag + "OK LOGIN completed");
+						}
+						else if (line.endsWith("LIST \"\" INBOX")) {
+							write("* LIST \"/\" \"\"");
+							write(tag + "OK LIST completed");
+						}
+						else if (line.endsWith("EXAMINE \"\"")) {
+							write("* 1 EXISTS");
+							write("* 1 RECENT");
+							write("* OK [UNSEEN 1]");
+							write(tag + "OK EXAMINE completed");
+						}
+						else if (line.endsWith("SEARCH NOT (FLAGGED) ALL")) {
+							write("* SEARCH 1 1");
+							write(tag + "OK SEARCH completed");
+						}
+						else if (line.contains("FETCH 1,1")) {
+							write("* 1 FETCH (RFC822.SIZE 6909 INTERNALDATE \"27-May-2013 09:45:41 +0000\" "
+									+ "FLAGS (\\Seen) "
+									+ "ENVELOPE (\"Mon, 27 May 2013 15:14:49 +0530\" "
+									+ "\"Test Email\" ((\"Foo\" NIL \"foo\" \"bar.tv\")) "
+									+ "((\"Foo\" NIL \"foo\" \"bar.tv\")) "
+									+ "((\"Foo\" NIL \"foo\" \"bar.tv\")) "
+									+ "((\"Bar\" NIL \"bar\" \"baz.net\")) NIL NIL "
+									+ "\"<4DA0A7E4.3010506@baz.net>\" "
+									+ "\"<CACVnpJkAUUfa3d_-4GNZW2WpxbB39tBCHC=T0gc7hty6dOEHcA@foo.bar.com>\") "
+									+ "BODYSTRUCTURE (\"TEXT\" \"PLAIN\" (\"CHARSET\" \"ISO-8859-1\") NIL NIL \"7BIT\" 1176 43)))");
+							write(tag + "OK FETCH completed");
+						}
+						else if (line.contains("STORE 1 +FLAGS (\\Flagged)")) {
+							write("* 1 FETCH (FLAGS (\\Flagged))");
+							write(tag + "OK STORE completed");
+						}
+						else if (line.contains("STORE 1 +FLAGS (\\Seen)")) {
+							write("* 1 FETCH (FLAGS (\\Flagged \\Seen))");
+							write(tag + "OK STORE completed");
+						}
+						else if (line.contains("FETCH 1 FLAGS")) {
+							write("* 1 FLAGS(\\Seen)");
+							write(tag + "OK FETCH completed");
+						}
+						else if (line.contains("FETCH 1 (BODY.PEEK")) {
+							write("* 1 FETCH (BODY[]<0> {" + (MESSAGE.length() + 2) + "}");
+							write(MESSAGE);
+							write(")");
+							write(tag + "OK FETCH completed");
+						}
+						else if (line.contains("CLOSE")) {
+							write(tag + "OK CLOSE completed");
+						}
+						else if (line.contains("NOOP")) {
+							write(tag + "OK NOOP completed");
+						}
+					}
+				}
+				catch (IOException e) {
+					e.printStackTrace();
+				}
+			}
+
+		}
+
+	}
+
+	public abstract static class MailServer implements Runnable {
+
+		private final ServerSocket socket;
+
+		private final ExecutorService exec = Executors.newCachedThreadPool();
+
+		protected final List<String> messages = new ArrayList<String>();
+
+		private volatile boolean listening;
+
+		public MailServer(int port) throws IOException {
+			this.socket = ServerSocketFactory.getDefault().createServerSocket(port);
+			this.listening = true;
+			exec.execute(this);
+		}
+
+		public boolean isListening() {
+			return listening;
+		}
+
+		public List<String> getMessages() {
+			return messages;
+		}
+
+		@Override
+		public void run() {
+			try {
+				while (!socket.isClosed()) {
+					Socket socket = this.socket.accept();
+					exec.execute(mailHandler(socket));
+				}
+			}
+			catch (IOException e) {
+				this.listening = false;
+			}
+		}
+
+		protected abstract MailHandler mailHandler(Socket socket);
+
+		public void stop() {
+			try {
+				this.socket.close();
+			}
+			catch (IOException e) {
+				e.printStackTrace();
+			}
+			this.exec.shutdownNow();
+		}
+
+		public abstract class MailHandler implements Runnable {
+
+			protected static final String MESSAGE = "To: foo@bar\r\nFrom: bar@baz\r\nSubject: Test Email\r\n\r\nfoo";
+
+			protected final Socket socket;
+
+			private BufferedWriter writer;
+
+			protected StringBuilder sb = new StringBuilder();
+
+			protected BufferedReader reader;
+
+			public MailHandler(Socket socket) {
+				this.socket = socket;
+			}
+
+			@Override
+			public void run() {
+				try {
+					this.reader = new BufferedReader(new InputStreamReader(this.socket.getInputStream()));
+					this.writer = new BufferedWriter(new OutputStreamWriter(this.socket.getOutputStream()));
+				}
+				catch (IOException e) {
+					e.printStackTrace();
+				}
+				doRun();
+			}
+
+			protected void write(String str) throws IOException {
 				this.writer.write(str);
 				this.writer.write("\r\n");
 				this.writer.flush();
 			}
 
+			abstract void doRun();
 
 		}