<appender name="EMAIL" class="ch.qos.logback.classic.net.SMTPAppender">
	      <Subject>TESTING: %logger{20} - %m</Subject>

               <SMTPHost>${smtpHost}</SMTPHost>
               <To>${to}</To>
               <From>${from}</From>
		<charsetEncoding>utf-8</charsetEncoding>
		<includeCallerData>true</includeCallerData>
  
		<layout class="ch.qos.logback.classic.PatternLayout">
			<pattern>%d{yyyy-MM-dd HH:mm:ss} %-5level \(%F:%L\) %method\(\) - %m%n</pattern>
		</layout>

		<cyclicBufferTracker class="ch.qos.logback.core.spi.CyclicBufferTracker">
			<bufferSize>2</bufferSize>
		</cyclicBufferTracker>
	</appender>

public class HelloWorldTest {

    private static final Logger log = LoggerFactory.getLogger(HelloWorldTest.class);

    @Test
    public void testHelloWorldTest() throws InterruptedException {
        for (int i = 0; i < 3; ++i) {
            log.error("hello world");
        }
        Thread.sleep(TimeInterval.SECONDS_PER_MINUTE * 1000);
    }
}