allow timeout to be specified as a duration

logback-classic/src/test/input/joran/sift/timeout.xml

@@ -9,7 +9,7 @@
             <key>timeout</key>
             <defaultValue>smoke</defaultValue>
         </discriminator>
-        <timeout>30000</timeout>
+        <timeout>30 seconds</timeout>
         <sift>
             <appender name="list-${userid}"
                       class="ch.qos.logback.core.read.ListAppender"/>

logback-core/src/main/java/ch/qos/logback/core/sift/SiftingAppenderBase.java

@@ -15,6 +15,7 @@
 
 import ch.qos.logback.core.Appender;
 import ch.qos.logback.core.AppenderBase;
+import ch.qos.logback.core.util.Duration;
 
 /**
  * This appender serves as the base class for actual SiftingAppenders
@@ -31,16 +32,16 @@ public abstract class SiftingAppenderBase<E> extends
 
   protected AppenderTracker<E> appenderTracker;
   AppenderFactory<E> appenderFactory;
-  int timeout = AppenderTracker.DEFAULT_TIMEOUT;
+  Duration timeout = new Duration(AppenderTracker.DEFAULT_TIMEOUT);
   int maxAppenderCount = AppenderTracker.DEFAULT_MAX_COMPONENTS;
 
   Discriminator<E> discriminator;
 
-  public int getTimeout() {
+  public Duration getTimeout() {
     return timeout;
   }
 
-  public void setTimeout(int timeout) {
+  public void setTimeout(Duration timeout) {
     this.timeout = timeout;
   }
 
@@ -77,7 +78,7 @@ public void start() {
     } else {
       appenderTracker = new AppenderTracker<E>(context, appenderFactory);
       appenderTracker.setMaxComponents(maxAppenderCount);
-      appenderTracker.setTimeout(timeout);
+      appenderTracker.setTimeout(timeout.getMilliseconds());
     }
     if (errors == 0) {
       super.start();

logback-core/src/main/java/ch/qos/logback/core/util/Duration.java

@@ -18,14 +18,13 @@
 
 /**
  * Duration instances represent a lapse of time. Internally, the duration is
- * stored in milliseconds.
- * <p>
- * 
- * The {@link #valueOf} method can convert strings such as "3.5 minutes", "5
- * hours", into Duration instances. The recognized units of time are the
- * "millisecond", "second", "minute" "hour" and "day". The unit name may be
- * followed by an "s". Thus, "2 day" and "2 days" are equivalent. In the absence
- * of a time unit specification, milliseconds are assumed.
+ * stored in milliseconds. This class follows the {@link #valueOf} convention meaning that it can
+ * convert an appropriately formatted string into a Duration object.
+ *
+ * <p>For example, string such as "3.5 minutes" or "5 hours" can be converted into Durations.
+ * The recognized units of time are the "millisecond", "second", "minute" "hour" and "day".
+ * The unit name may be followed by an "s". Thus, "2 day" and "2 days" are equivalent. In the
+ * absence of a time unit specification, milliseconds are assumed.
  * 
  * 
  * @author Ceki Gulcu

logback-site/src/site/pages/manual/appenders.html

@@ -3642,15 +3642,43 @@ <h3 class="doAnchor" name="SiftingAppender">SiftingAppender</h3>
     </p>
 
 
+
+    <table class="bodyTable striped">
+			<tr>
+				<th>Property Name</th>
+				<th>Type</th>
+				<th>Description</th>
+			</tr>
+			<tr>
+				<td><span class="prop" container="sift">timeout</span></td>
+				<td><code><a href="../apidocs/ch/qos/logback/core/util/Duration.html">Duration</a></code></td>
+				<td>A nested appender which has not been accessed beyond the
+				<span class="prop">timeout</span> duration is deemed stale. A
+				stale appender is closed and unreferenced by
+				<code>SiftingAppender</code>. The dfault value for <span
+				class="prop">timeout</span> is 30 minutes.</td>
+			</tr>
+			<tr>
+				<td><span class="prop" container="sift">maxAppenderCount</span></td>
+				<td><code>integer</code></td>
+				<td>The maximum number of nested appenders
+				<code>SiftingAppender</code> may create and track. Default
+				value for <span class="prop">maxAppenderCount</span> is
+				Integer.MAX_VALUE.</td>
+			</tr>
+  </table>
+
     <p><code>SiftingAppender</code> achieves this feat by creating
-    child appenders on the fly. Child appenders are created based on a
-    template specified within the configuration of the
+    nested appenders on the fly. Nested appenders are created based on
+    a template specified within the configuration of the
     <code>SiftingAppender</code> itself (enclosed within the
     <code>&lt;sift></code> element, see example
     below). <code>SiftingAppender</code> is responsible for managing
     the lifecycle of child appenders. For example,
     <code>SiftingAppender</code> will automatically close and remove
-    any unused child appender.
+    any stale appender. A nested appender is considered stale when no
+    accesses it beyond the duration specified by the <span
+    class="prop">timeout</span> parameter.
     </p>
 
     <p>When handling a logging event, <code>SiftingAppender</code>

logback-site/src/site/pages/news.html

@@ -64,7 +64,6 @@ <h3>April, 2013 - Release of version 1.0.12</h3>
     <a href="manual/appenders.html#serverSocketAppender">ServerSocketAppender</a>
     for information on configuring appenders as event sources for
     receiver components.</p>
-
 
     <p><code>RollingFileAppender</code> will now detect when <span
     class="option">file</span> property collides with <span
@@ -95,15 +94,21 @@ <h3>April, 2013 - Release of version 1.0.12</h3>
     <p class="highlight">Groovy configurator no longer supports
     SiftingAppender.</p>
 
-    <p>Component tracking code has been simplified and completely
-    re-written. As a result of these changes, the groovy configurator
+    <p>In response to <a
+    href="http://jira.qos.ch/browse/LOGBACK-244">LOGBACK-244</a>, <a
+    href="http://jira.qos.ch/browse/LOGBACK-724">LOGBACK-724</a> and
+    in particular patches provided by Tommy Becker and David Roussel
+    component tracking code has been simplified and completely
+    re-written. SiftingAppender now supports timeout and
+    maxAppenderCount parameter. As a direct consequence of
+    modificatons to component tracking code, the groovy configurator
     no longer supports <code>SiftingAppender</code>.</p>
 
     <p>SiftingAppender now propagates properties defined elsewhere in
     the configuration file into the configuration process of nested
     appenders. This fixes <a
     href="http://jira.qos.ch/browse/LOGBACK-833">LOGBACK-833</a> with
-    David Roussel providing the appropriate patch..
+    David Roussel providing the appropriate patch.
     </p>
 
     <p>As all other actions affecting properties,