Use slf4j simple logger to get logs to stdout

Logs were heading over to log4j before this; were they getting lost?

build.gradle

@@ -39,11 +39,18 @@ dependencies {
 
     compile 'org.apache.kafka:kafka_2.10:0.8.1.1+'
 
+    compile 'org.slf4j:log4j-over-slf4j:1.7.6'
+    compile 'org.slf4j:slf4j-simple:1.7.6'
+
     testCompile 'org.spockframework:spock-core:0.7-groovy-2.0'
     testCompile 'cglib:cglib-nodep:2.2.+'
 }
 ////////////////////////////////////////////////////////////////////////////////
 
+configurations {
+    compile.exclude module: 'log4j'
+    compile.exclude module: 'slf4j-log4j12'
+}
 
 test {
     testLogging {

src/main/groovy/offtopic/KafkaSubscriber.groovy

@@ -4,11 +4,13 @@ import kafka.consumer.ConsumerConfig;
 import kafka.consumer.KafkaStream;
 import kafka.javaapi.consumer.ConsumerConnector;
 import offtopic.curator.CuratorPool
+import groovy.util.logging.Slf4j
 
 /**
  * KafkaSubscriber is a Kafka consumer consumer, largely cribbed from:
  * https://cwiki.apache.org/confluence/display/KAFKA/Consumer+Group+Example
  */
+@Slf4j
 class KafkaSubscriber {
 
     String topic
@@ -38,7 +40,7 @@ class KafkaSubscriber {
 
     public void consume() {
         if (this.consumer == null) {
-            println "no consumer, gtfo"
+            log.warn "no consumer, gtfo"
             return
         }
 

src/main/groovy/offtopic/OfftopicClient.groovy

@@ -1,9 +1,12 @@
 package offtopic
 
+import groovy.util.logging.Slf4j
+
 /**
  * OfftopicClient coordinates the interactions between KafkaSubscriber objects
  * and the websocket interactions
  */
+@Slf4j
 class OfftopicClient {
     public int clientId = 0
 
@@ -44,9 +47,9 @@ class OfftopicClient {
         this.subscribers.each { subscriber ->
             Thread runner = new Thread({
                 subscriber.connect()
-                println "subscriber connected"
+                log.info "subscriber connected"
                 subscriber.consume()
-                println "consume over!"
+                log.info "consume over!"
             })
             runner.start()
         }