title: How to fix "SLF4J: Class path contains multiple SLF4J bindings" at startup of Play 2.3.x?
body: <p>I upgraded my version of Play and other libraries and I now see this:</p>
  
  <pre><code>SLF4J: Class path contains multiple SLF4J bindings.
  SLF4J: Found binding in [jar:file:/home/paul/.ivy2/cache/org.slf4j/slf4j-nop/jars/slf4j-nop-1.7.7.jar!/org/slf4j/impl/StaticLoggerBinder.class]
  SLF4J: Found binding in [jar:file:/home/paul/.ivy2/cache/org.slf4j/slf4j-jdk14/jars/slf4j-jdk14-1.7.7.jar!/org/slf4j/impl/StaticLoggerBinder.class]
  SLF4J: Found binding in [jar:file:/home/paul/.ivy2/cache/org.slf4j/slf4j-simple/jars/slf4j-simple-1.7.7.jar!/org/slf4j/impl/StaticLoggerBinder.class]
  SLF4J: See http://www.slf4j.org/codes.html#multiple_bindings for an explanation.
  SLF4J: Actual binding is of type [org.slf4j.helpers.NOPLoggerFactory]
  </code></pre>
  
  <p>I am trying to track down where these are coming from, but when I run <code>show managed-classpath</code>, the only slf4j jars are</p>
  
  <pre><code>/home/paul/.ivy2/cache/org.slf4j/slf4j-api/jars/slf4j-api-1.7.6.jar
  /home/paul/.ivy2/cache/org.slf4j/jul-to-slf4j/jars/jul-to-slf4j-1.7.6.ja
  /home/paul/.ivy2/cache/org.slf4j/jcl-over-slf4j/jars/jcl-over-slf4j-1.7.6.jar
  </code></pre>
  
  <p>I never see <code>slf4j-nop-1.7.7.jar</code> or <code>slf4j-jdk14-1.7.7.jar</code> or <code>slf4j-simple-1.7.7.jar</code>.</p>
  
  <p>How are these on the classpath?</p>