#64: added support for flagged mode that doesn't send emails, but jus…

…t logs it

src/main/java/org/simplejavamail/mailer/Mailer.java

@@ -261,6 +261,22 @@ public void setDebug(final boolean debug) {
 		mailSender.setDebug(debug);
 	}
 
+	/**
+	 * Sets the transport mode for this mail sender to logging only, which means no mail will be actually sent out.
+	 *
+	 * @param transportModeLoggingOnly Flag to indicate logging mode yes/no.
+	 */
+	public synchronized void setTransportModeLoggingOnly(boolean transportModeLoggingOnly) {
+		mailSender.setTransportModeLoggingOnly(transportModeLoggingOnly);
+	}
+
+	/**
+	 * @return Whether this Mailer is set to only log or also actually send emails through an SMTP server (which is the default).
+	 */
+	public boolean isTransportModeLoggingOnly() {
+		return mailSender.isTransportModeLoggingOnly();
+	}
+
 	/**
 	 * Configures the current session to trust all hosts and don't validate any SSL keys. The property "mail.smtp.ssl.trust" is set to "*".
 	 * <p>

src/main/java/org/simplejavamail/mailer/internal/mailsender/MailSender.java

@@ -2,17 +2,19 @@
 
 import org.simplejavamail.MailException;
 import org.simplejavamail.email.Email;
-import org.simplejavamail.util.ConfigLoader;
-import org.simplejavamail.util.ConfigLoader.Property;
 import org.simplejavamail.mailer.config.ProxyConfig;
 import org.simplejavamail.mailer.config.TransportStrategy;
 import org.simplejavamail.mailer.internal.socks.AuthenticatingSocks5Bridge;
 import org.simplejavamail.mailer.internal.socks.socks5server.AnonymousSocks5Server;
+import org.simplejavamail.util.ConfigLoader;
+import org.simplejavamail.util.ConfigLoader.Property;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
 import javax.mail.*;
 import javax.mail.internet.MimeMessage;
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
 import java.io.UnsupportedEncodingException;
 import java.util.Properties;
 import java.util.concurrent.ExecutorService;
@@ -71,13 +73,19 @@ public class MailSender {
 
 	private int threadPoolSize;
 
+	/**
+	 * Determines whether at the very last moment an email is sent out using JavaMail's native API or whether the email is simply only logged.
+	 */
+	private boolean transportModeLoggingOnly;
+
 	/**
 	 * @see #configureSessionWithProxy(ProxyConfig, Session, TransportStrategy)
 	 */
 	public MailSender(final Session session, final ProxyConfig proxyConfig, final TransportStrategy transportStrategy) {
 		this.session = session;
 		this.proxyServer = configureSessionWithProxy(proxyConfig, session, transportStrategy);
 		this.threadPoolSize = ConfigLoader.valueOrProperty(null, Property.DEFAULT_POOL_SIZE, DEFAULT_POOL_SIZE);
+		this.transportModeLoggingOnly = ConfigLoader.valueOrProperty(null, Property.TRANSPORT_MODE_LOGGING_ONLY, false);
 	}
 
 	/**
@@ -186,13 +194,23 @@ private void sendMailClosure(final Session session, final Email email) {
 						proxyServer.start();
 					}
 				}
-				try {
-					transport.connect();
-					transport.sendMessage(message, message.getAllRecipients());
-				} finally {
-					LOGGER.trace("closing transport");
-					//noinspection ThrowFromFinallyBlock
-					transport.close();
+
+				if (!transportModeLoggingOnly) {
+					LOGGER.trace("\t\nEmail: {}", email);
+					LOGGER.trace("\t\nMimeMessage: {}\n", readMimeMessageToString(message));
+
+					try {
+						transport.connect();
+						transport.sendMessage(message, message.getAllRecipients());
+					} finally {
+						LOGGER.trace("closing transport");
+						//noinspection ThrowFromFinallyBlock
+						transport.close();
+					}
+				} else {
+					LOGGER.info("TRANSPORT_MODE_LOGGING_ONLY: skipping actual sending...");
+					LOGGER.info("\n\nEmail: {}\n", email);
+					LOGGER.info("\n\nMimeMessage: {}\n", readMimeMessageToString(message));
 				}
 			} finally {
 				checkShutDownProxyBridge();
@@ -204,6 +222,16 @@ private void sendMailClosure(final Session session, final Email email) {
 		}
 	}
 
+	private String readMimeMessageToString(MimeMessage message) {
+		ByteArrayOutputStream os = new ByteArrayOutputStream();
+		try {
+			message.writeTo(os);
+			return os.toString("UTF-8");
+		} catch (IOException | MessagingException e) {
+			throw new RuntimeException(e.getMessage(), e);
+		}
+	}
+
 	/**
 	 * We need to keep a count of running threads only if we need to shutdown the proxy bridging server at the end in async mode.
 	 * <p>
@@ -297,4 +325,17 @@ public synchronized void setThreadPoolSize(int threadPoolSize) {
 		this.threadPoolSize = threadPoolSize;
 	}
 
-}
+	/**
+	 * Sets the transport mode for this mail sender to logging only, which means no mail will be actually sent out.
+	 */
+	public synchronized void setTransportModeLoggingOnly(boolean transportModeLoggingOnly) {
+		this.transportModeLoggingOnly = transportModeLoggingOnly;
+	}
+
+	/**
+	 * @return {@link #transportModeLoggingOnly}
+	 */
+	public boolean isTransportModeLoggingOnly() {
+		return transportModeLoggingOnly;
+	}
+}

src/main/java/org/simplejavamail/springsupport/SimpleJavaMailSpringSupport.java

@@ -38,7 +38,8 @@ public Mailer loadGlobalConfigAndCreateDefaultMailer(
 			@Value("${simplejavamail.defaults.cc.address:#{null}}") String defaultCcAddress,
 			@Value("${simplejavamail.defaults.bcc.name:#{null}}") String defaultBccName,
 			@Value("${simplejavamail.defaults.bcc.address:#{null}}") String defaultBccAddress,
-			@Value("${simplejavamail.defaults.poolsize:#{null}}") String defaultPoolsize) {
+			@Value("${simplejavamail.defaults.poolsize:#{null}}") String defaultPoolsize,
+			@Value("${simplejavamail.transport.mode.logging.only:#{null}}") String defaultTransportModeLoggingOnly) {
 		Properties emailProperties = new Properties();
 		setNullableProperty(emailProperties, Property.JAVAXMAIL_DEBUG.key(), javaxmailDebug);
 		setNullableProperty(emailProperties, Property.TRANSPORT_STRATEGY.key(), transportstrategy);
@@ -63,6 +64,7 @@ public Mailer loadGlobalConfigAndCreateDefaultMailer(
 		setNullableProperty(emailProperties, Property.DEFAULT_BCC_NAME.key(), defaultBccName);
 		setNullableProperty(emailProperties, Property.DEFAULT_BCC_ADDRESS.key(), defaultBccAddress);
 		setNullableProperty(emailProperties, Property.DEFAULT_POOL_SIZE.key(), defaultPoolsize);
+		setNullableProperty(emailProperties, Property.TRANSPORT_MODE_LOGGING_ONLY.key(), defaultTransportModeLoggingOnly);
 
 		ConfigLoader.loadProperties(emailProperties, true);
 

src/main/java/org/simplejavamail/util/ConfigLoader.java

@@ -45,7 +45,8 @@
  *    <li>simplejavamail.defaults.cc.address</li>
  *    <li>simplejavamail.defaults.bcc.name</li>
  *    <li>simplejavamail.defaults.bcc.address</li>
- *    <li>simplejavamail.defaults.poolsize
+ *    <li>simplejavamail.defaults.poolsize</li>
+ *    <li>simplejavamail.transport.mode.logging.only</li>
  * </ul></pre>
  */
 public final class ConfigLoader {
@@ -92,7 +93,8 @@ public enum Property {
 		DEFAULT_CC_ADDRESS("simplejavamail.defaults.cc.address"),
 		DEFAULT_BCC_NAME("simplejavamail.defaults.bcc.name"),
 		DEFAULT_BCC_ADDRESS("simplejavamail.defaults.bcc.address"),
-		DEFAULT_POOL_SIZE("simplejavamail.defaults.poolsize");
+		DEFAULT_POOL_SIZE("simplejavamail.defaults.poolsize"),
+		TRANSPORT_MODE_LOGGING_ONLY("simplejavamail.transport.mode.logging.only");
 
 		private final String key;
 
@@ -113,6 +115,9 @@ public static <T> T valueOrProperty(final T value, final Property property) {
 	}
 
 	/**
+	 * Returns the given value if not null and not empty, otherwise tries to resolve the given property and if still not found resot to the default value if
+	 * provided.
+	 * <p>
 	 * Null or blank values are never allowed, so they are always ignored.
 	 *
 	 * @return The value if not null or else the value from config file if provided or else <code>defaultValue</code>.

src/test/java/demo/MailTestApp.java

@@ -31,8 +31,14 @@ public class MailTestApp {
 	private static final ServerConfig serverConfigTLS = new ServerConfig("smtp.gmail.com", 587, YOUR_GMAIL_ADDRESS, YOUR_GMAIL_PASSWORD);
 	private static final ServerConfig serverConfigSSL = new ServerConfig("smtp.gmail.com", 465, YOUR_GMAIL_ADDRESS, YOUR_GMAIL_PASSWORD);
 
+	/**
+	 * If you just want to see what email is being sent, just set this to true. It won't actually connect to an SMTP server then.
+	 */
+	private static final boolean LOGGING_MODE = false;
+
 	public static void main(final String[] args)
 			throws Exception {
+		// make Simple Java Mail ignore the properties file completely: that's there for the junit tests, not this demo.
 		ConfigLoaderTestHelper.clearConfigProperties();
 
 		final Email emailNormal = new Email();
@@ -58,10 +64,17 @@ public static void main(final String[] args)
 		sendMail(emailFromMimeMessage); // should produce the exact same result as emailNormal!
 	}
 
-	private static void sendMail(final Email email) {
+	private static void sendMail(final Email email)
+			throws ClassNotFoundException {
 		// ProxyConfig proxyconfig = new ProxyConfig("localhost", 1030);
-		new Mailer(serverConfigSMTP, TransportStrategy.SMTP_TLS).sendMail(email);
-		new Mailer(serverConfigTLS, TransportStrategy.SMTP_TLS).sendMail(email);
-		new Mailer(serverConfigSSL, TransportStrategy.SMTP_SSL).sendMail(email);
+		sendMail(serverConfigSMTP, TransportStrategy.SMTP_TLS, email);
+		sendMail(serverConfigTLS, TransportStrategy.SMTP_TLS, email);
+		sendMail(serverConfigSSL, TransportStrategy.SMTP_SSL, email);
+	}
+
+	private static void sendMail(ServerConfig serverConfigSMTP, TransportStrategy smtpTls, Email email) {
+		Mailer mailer = new Mailer(serverConfigSMTP, smtpTls);
+		mailer.setTransportModeLoggingOnly(LOGGING_MODE);
+		mailer.sendMail(email);
 	}
 }

src/test/java/org/simplejavamail/mailer/internal/mailsender/MailSenderTest.java

@@ -46,5 +46,4 @@ public void trustHosts(){
 		mailSender.trustHosts("a", "b", "c");
 		assertThat(session.getProperties().getProperty("mail.smtp.ssl.trust")).isEqualTo("a,b,c");
 	}
-
 }

src/test/resources/ignore.properties

@@ -6,7 +6,7 @@ simplejavamail.smtp.port=moo
 simplejavamail.smtp.username=moo
 simplejavamail.smtp.password=moo
 simplejavamail.proxy.host=moo
-PROXY_PORT("simplejavamail.proxy.port=moo
+simplejavamail.proxy.port=moo
 simplejavamail.proxy.username=moo
 simplejavamail.proxy.password=moo
 simplejavamail.proxy.socks5bridge.port=moo
@@ -19,4 +19,5 @@ simplejavamail.defaults.to.address=moo
 simplejavamail.defaults.cc.name=moo
 simplejavamail.defaults.cc.address=moo
 simplejavamail.defaults.bcc.name=moo
-simplejavamail.defaults.bcc.address=moo
+simplejavamail.defaults.bcc.address=moo
+simplejavamail.transport.mode.logging.only=moo

src/test/resources/simplejavamail.properties

@@ -19,4 +19,5 @@ simplejavamail.defaults.to.address=to@default.com
 simplejavamail.defaults.cc.name=CC Default
 simplejavamail.defaults.cc.address=cc@default.com
 simplejavamail.defaults.bcc.name=BCC Default
-simplejavamail.defaults.bcc.address=bcc@default.com
+simplejavamail.defaults.bcc.address=bcc@default.com
+simplejavamail.transport.mode.logging.only=false