Rename event-handlers to loggers, see #2979

* Rename config akka.event-handlers to akka.loggers
* Rename config akka.event-handler-startup-timeout to
  akka.logger-startup-timeout
* Rename JulEventHandler to JavaLogger
* Rename Slf4jEventHandler to Slf4jLogger
* Change all places in tests and docs
* Deprecation, old still works, but with warnings
* Migration guide
* Test for the deprecated event-handler config

akka-docs/rst/java/code/docs/testkit/TestKitDocTest.java

@@ -50,7 +50,7 @@ public class TestKitDocTest {
   @BeforeClass
   public static void setup() {
     final Config config = ConfigFactory.parseString(
-        "akka.event-handlers = [akka.testkit.TestEventListener]");
+        "akka.loggers = [akka.testkit.TestEventListener]");
     system = ActorSystem.create("demoSystem", config);
   }
   

akka-docs/rst/java/event-bus.rst

@@ -175,7 +175,7 @@ stream for logging: these are the handlers which are configured for example in
 .. code-block:: text
 
   akka {
-    event-handlers = ["akka.event.Logging$DefaultLogger"]
+    loggers = ["akka.event.Logging$DefaultLogger"]
   }
 
 The handlers listed here by fully-qualified class name will be subscribed to

akka-docs/rst/java/logging.rst

@@ -154,24 +154,25 @@ If you want to see all messages that are received through remoting at DEBUG log
 Also see the logging options for TestKit: :ref:`actor.logging-java`.
 
 
-Event Handler
-=============
+Loggers
+=======
 
-Logging is performed asynchronously through an event bus. You can configure which event handlers that should
-subscribe to the logging events. That is done using the 'event-handlers' element in the :ref:`configuration`.
+Logging is performed asynchronously through an event bus. You can configure which loggers that should
+subscribe to the logging events. That is done using the 'loggers' element in the :ref:`configuration`.
 Here you can also define the log level.
 
 .. code-block:: ruby
 
   akka {
-    # Event handlers to register at boot time (Logging$DefaultLogger logs to STDOUT)
-    event-handlers = ["akka.event.Logging$DefaultLogger"]
+    # Loggers to register at boot time (akka.event.Logging$DefaultLogger logs
+    # to STDOUT)
+    loggers = ["akka.event.Logging$DefaultLogger"]
     # Options: ERROR, WARNING, INFO, DEBUG
     loglevel = "DEBUG"
   }
 
 The default one logs to STDOUT and is registered by default. It is not intended to be used for production. There is also an :ref:`slf4j-java`
-event handler available in the 'akka-slf4j' module.
+logger available in the 'akka-slf4j' module.
 
 Example of creating a listener:
 
@@ -186,7 +187,7 @@ Example of creating a listener:
 SLF4J
 =====
 
-Akka provides an event handler for `SL4FJ <http://www.slf4j.org/>`_. This module is available in the 'akka-slf4j.jar'.
+Akka provides a logger for `SL4FJ <http://www.slf4j.org/>`_. This module is available in the 'akka-slf4j.jar'.
 It has one single dependency; the slf4j-api jar. In runtime you also need a SLF4J backend, we recommend `Logback <http://logback.qos.ch/>`_:
 
   .. code-block:: xml
@@ -197,7 +198,7 @@ It has one single dependency; the slf4j-api jar. In runtime you also need a SLF4
        <version>1.0.7</version>
      </dependency>
 
-You need to enable the Slf4jEventHandler in the 'event-handlers' element in
+You need to enable the Slf4jLogger in the 'loggers' element in
 the :ref:`configuration`. Here you can also define the log level of the event bus.
 More fine grained log levels can be defined in the configuration of the SLF4J backend
 (e.g. logback.xml).
@@ -205,7 +206,7 @@ More fine grained log levels can be defined in the configuration of the SLF4J ba
 .. code-block:: ruby
 
   akka {
-    event-handlers = ["akka.event.slf4j.Slf4jEventHandler"]
+    loggers = ["akka.event.slf4j.Slf4jLogger"]
     loglevel = "DEBUG"
   }
 

akka-docs/rst/java/testing.rst

@@ -305,11 +305,11 @@ fails.
 
 .. note::
 
-   Be sure to exchange the default event handler with the
+   Be sure to exchange the default logger with the
    :class:`TestEventListener` in your ``application.conf`` to enable this
    function::
 
-     akka.event-handlers = [akka.testkit.TestEventListener]
+     akka.loggers = [akka.testkit.TestEventListener]
 
 .. _JavaTestKit.within: