added threadId converter, configured its aliases, and improved javadoc

Author: rob93c

logback-classic/src/main/java/ch/qos/logback/classic/PatternLayout.java

@@ -25,17 +25,14 @@
 import ch.qos.logback.core.pattern.parser.Parser;
 
 /**
- * <p>
  * A flexible layout configurable with pattern string. The goal of this class is
- * to {@link #format format} a {@link ILoggingEvent} and return the results in a
- * {#link String}. The format of the result depends on the <em>conversion
+ * to format a {@link ILoggingEvent} and return the results in a
+ * {@link String}. The format of the result depends on the <em>conversion
  * pattern</em>.
  * <p>
- * For more information about this layout, please refer to the online manual at
- * http://logback.qos.ch/manual/layouts.html#PatternLayout
- * 
+ * For more information about this layout, please refer to
+ * <a href="http://logback.qos.ch/manual/layouts.html#PatternLayout">the online manual</a>.
  */
-
 public class PatternLayout extends PatternLayoutBase<ILoggingEvent> {
 
     public static final Map<String, String> DEFAULT_CONVERTER_MAP = new HashMap<String, String>();
@@ -73,6 +70,10 @@ public class PatternLayout extends PatternLayoutBase<ILoggingEvent> {
         DEFAULT_CONVERTER_MAP.put("thread", ThreadConverter.class.getName());
         CONVERTER_CLASS_TO_KEY_MAP.put(ThreadConverter.class.getName(), "thread");
 
+        DEFAULT_CONVERTER_MAP.put("tid", ThreadIdConverter.class.getName());
+        DEFAULT_CONVERTER_MAP.put("threadId", ThreadIdConverter.class.getName());
+        CONVERTER_CLASS_TO_KEY_MAP.put(ThreadIdConverter.class.getName(), "threadId");
+
         DEFAULT_CONVERTER_MAP.put("lo", LoggerConverter.class.getName());
         DEFAULT_CONVERTER_MAP.put("logger", LoggerConverter.class.getName());
         DEFAULT_CONVERTER_MAP.put("c", LoggerConverter.class.getName());

logback-classic/src/main/java/ch/qos/logback/classic/pattern/ThreadIdConverter.java

@@ -0,0 +1,29 @@
+/**
+ * Logback: the reliable, generic, fast and flexible logging framework.
+ * Copyright (C) 1999-2015, QOS.ch. All rights reserved.
+ *
+ * This program and the accompanying materials are dual-licensed under
+ * either the terms of the Eclipse Public License v1.0 as published by
+ * the Eclipse Foundation
+ *
+ *   or (per the licensee's choosing)
+ *
+ * under the terms of the GNU Lesser General Public License version 2.1
+ * as published by the Free Software Foundation.
+ */
+package ch.qos.logback.classic.pattern;
+
+import ch.qos.logback.classic.spi.ILoggingEvent;
+
+/**
+ * Returns the id of the current thread.
+ * 
+ * @author Roberto Cella
+ */
+public class ThreadIdConverter extends ClassicConverter {
+
+    public String convert(ILoggingEvent event) {
+        return String.valueOf(Thread.currentThread().getId());
+    }
+
+}