add thread safety

* access to currentBatchList was not protected by lock, leading to
  currentBatchList in flushBatch().
* also: fix javadoc warnings

7 files changed, 9 insertions, 22 deletions

diff --git a/logserver/src/main/java/com/yahoo/logserver/LogDispatcher.java b/logserver/src/main/java/com/yahoo/logserver/LogDispatcher.java
index f7828b4dc9f..e13a2f09323 100644
--- a/logserver/src/main/java/com/yahoo/logserver/LogDispatcher.java
+++ b/logserver/src/main/java/com/yahoo/logserver/LogDispatcher.java
@@ -71,17 +71,17 @@ public class LogDispatcher implements LogHandler, SelectLoopHook {
     }
 
     private void flushBatch() {
-        if (currentBatchList == null) {
-            return;
+        List<LogMessage> todo;
+        synchronized(this) {
+            todo = currentBatchList;
+            currentBatchList = null;
         }
-
+        if (todo == null) return;
         for (LogHandler ht : handlers) {
-            ht.handle(currentBatchList);
+            ht.handle(todo);
         }
-        currentBatchList = null;
     }
 
-
     public void handle(List<LogMessage> messages) {
         throw new IllegalStateException("method not supported");
     }
@@ -132,7 +132,6 @@ public class LogDispatcher implements LogHandler, SelectLoopHook {
      * thread has already been registered, we log a warning and
      * just do nothing.
      * <p>
-     * <p>
      * If the thread is not alive it will be start()'ed.
      */
     public synchronized void registerLogHandler(LogHandler ht) {
diff --git a/logserver/src/main/java/com/yahoo/logserver/PluginLoader.java b/logserver/src/main/java/com/yahoo/logserver/PluginLoader.java
index 6347226f5de..42355022f16 100644
--- a/logserver/src/main/java/com/yahoo/logserver/PluginLoader.java
+++ b/logserver/src/main/java/com/yahoo/logserver/PluginLoader.java
@@ -7,7 +7,6 @@ package com.yahoo.logserver;
  * all of its knows plugins.  In addition, if a plugin loader's
  * canReload() method returns <code>true</code>, plugins may be loaded
  * again after they are unloaded.
- * <p>
  * <p> Plugins loaded through such reload-capable plugin loaders may
  * be upgraded without restarting the server.
  *
diff --git a/logserver/src/main/java/com/yahoo/logserver/handlers/AbstractLogHandler.java b/logserver/src/main/java/com/yahoo/logserver/handlers/AbstractLogHandler.java
index a2da987f802..362312434d3 100644
--- a/logserver/src/main/java/com/yahoo/logserver/handlers/AbstractLogHandler.java
+++ b/logserver/src/main/java/com/yahoo/logserver/handlers/AbstractLogHandler.java
@@ -101,7 +101,6 @@ public abstract class AbstractLogHandler implements LogHandler {
      * does something to it.  This is the one you wish to
      * override when you write a new handler.
      * <p>
-     * <p>
      * <em>
      * If your handle method is slow you should document this fact
      * so that decisions can be made with regard to configuration.
@@ -123,7 +122,6 @@ public abstract class AbstractLogHandler implements LogHandler {
      * the #handle() has undefined behavior, but it should be assumed
      * that log messages will be silently dropped.
      * <p>
-     * <p>
      * #close() usually implies #flush() but don't bet on it.
      */
     public abstract void close();
diff --git a/logserver/src/main/java/com/yahoo/logserver/handlers/archive/ArchiverHandler.java b/logserver/src/main/java/com/yahoo/logserver/handlers/archive/ArchiverHandler.java
index d2a3d566c38..b1169aff02e 100644
--- a/logserver/src/main/java/com/yahoo/logserver/handlers/archive/ArchiverHandler.java
+++ b/logserver/src/main/java/com/yahoo/logserver/handlers/archive/ArchiverHandler.java
@@ -25,28 +25,26 @@ import com.yahoo.logserver.handlers.AbstractLogHandler;
  * is to make it easy to locate messages in a time interval, while
  * ensuring that no log file exceeds the maximum allowed size.
  * <p>
- * <p>
  * This class is not thread safe.
  * </p>
  * <p>
- * <p>
  * TODO:
  * </p>
  * <ul>
  * <li> Add file locking support in order to make it
  * possible to do concurrent compression of log
  * files.
- * <p>
+ * </li>
  * <li> Add support for disk monitoring.  Should have
  * high/low watermark mechanism and three modes
  * of operation: normal, tight and full.  In
  * "tight" mode disk is running low and compression
  * and cleanup should possibly be more frequent.
- * <p>
+ * </li>
  * <li> Add compression task which periodically scans
  * the log directory looking for uncompressed
  * candidate log files.
- * <p>
+ * </li>
  * </ul>
  *
  * @author Bjorn Borud
@@ -151,7 +149,6 @@ public class ArchiverHandler extends AbstractLogHandler {
      * down number representing year, month, day and hour in order
      * to partition logging in time.
      * <p>
-     * <p>
      * This method is not thread-safe.
      */
     public int dateHash(long time) {
@@ -170,7 +167,6 @@ public class ArchiverHandler extends AbstractLogHandler {
     /**
      * Generate prefix for log filenames based on log message.
      * <p>
-     * <p>
      * <EM>This message is <code>public</code> only because we need
      * access to it in unit tests.  For all practical purposes this
      * method does not exist to you, the application programmer, OK? :-)</EM>
diff --git a/logserver/src/main/java/com/yahoo/logserver/handlers/archive/LogWriter.java b/logserver/src/main/java/com/yahoo/logserver/handlers/archive/LogWriter.java
index 5fa7dd7f4b6..17af537026a 100644
--- a/logserver/src/main/java/com/yahoo/logserver/handlers/archive/LogWriter.java
+++ b/logserver/src/main/java/com/yahoo/logserver/handlers/archive/LogWriter.java
@@ -36,7 +36,6 @@ public class LogWriter extends Writer {
      * This is called when we want to rotate the output file to
      * start writing the next file.  There are two scenarios when
      * we do this:
-     * <p>
      * <UL>
      * <LI> initial case, when we have no file
      * <LI> when we have filled the file and want to rotate it
@@ -102,7 +101,6 @@ public class LogWriter extends Writer {
      * that would circumvent rotation when it grows past its
      * maximum size.  use the one that takes String instead.
      * <p>
-     * <p>
      * <em>
      * (This is a class which is only used internally anyway)
      * </em>
diff --git a/logserver/src/main/java/com/yahoo/logserver/handlers/replicator/FormattedBufferCache.java b/logserver/src/main/java/com/yahoo/logserver/handlers/replicator/FormattedBufferCache.java
index 284781b12bb..daf408c17a4 100644
--- a/logserver/src/main/java/com/yahoo/logserver/handlers/replicator/FormattedBufferCache.java
+++ b/logserver/src/main/java/com/yahoo/logserver/handlers/replicator/FormattedBufferCache.java
@@ -17,12 +17,10 @@ import com.yahoo.logserver.formatter.LogFormatterManager;
  * still ensuring we don't format more messages than we strictly need
  * to and that we don't keep around more buffers that we ought to.
  * <p>
- * <p>
  * This is not a general purpose class, I think, so please
  * refer to the source code of the Replicator class for
  * information on how to use this.
  * <p>
- * <p>
  * This class is not threadsafe.
  *
  * @author Bjorn Borud
diff --git a/logserver/src/main/java/com/yahoo/logserver/handlers/replicator/Replicator.java b/logserver/src/main/java/com/yahoo/logserver/handlers/replicator/Replicator.java
index 5ede34a1f79..1d8da93c483 100644
--- a/logserver/src/main/java/com/yahoo/logserver/handlers/replicator/Replicator.java
+++ b/logserver/src/main/java/com/yahoo/logserver/handlers/replicator/Replicator.java
@@ -18,7 +18,6 @@ import com.yahoo.logserver.handlers.AbstractLogHandler;
  * The Replicator plugin is used for replicating log messages sent
  * to the logserver.
  * <p>
- * <p>
  * Per default the replicator will start dropping messages enqueued
  * to a client if the outbound message queue reaches 5000 messages.
  * This limit can be configured by setting the system property