Merge branch 'stable-2.11'

* stable-2.11:
  Remove VERSION file
  Solver V1: Check for file/directory existence before operations
  AMQProperties: Fix IllegalArgumentException when setting properties
  Catch explicit exceptions instead of Exception
  Use AtomicInteger instead of volatile int
  Prevent potential null-pointer access
  Remove unnecessary constructor invocations
  Remove unnecessary casts
  Add missing @Override annotations
  Change logging message and level for closed connection.
  Create new AMQP properties for each publication
  Bump AMQP client to 3.5.2
  Fall back to loading only base config if no site configs are found
  Change logging message and level for failed connection.
  Add timestamp on messages
  Use API version 2.10.4
  Implement standalone Buck build
  Remove Gradle build
  Implement Buck build
  Better usage of builder patten in AMQProperties.getBasicProperties
  Build with API version 2.11

Change-Id: Ia9235595fd810e01e7749a31265ab1233f7d7206
diff --git a/.buckconfig b/.buckconfig
new file mode 100644
index 0000000..5238f0d
--- /dev/null
+++ b/.buckconfig
@@ -0,0 +1,13 @@
+[alias]
+  rabbitmq = //:rabbitmq
+  plugin = //:rabbitmq
+
+[java]
+  src_roots = java, resources
+
+[project]
+  ignore = .git
+
+[cache]
+  mode = dir
+  dir = buck-out/cache
diff --git a/.gitignore b/.gitignore
index 931312c..73faeb9 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,11 +1,15 @@
 work/
+buck-out/
+bucklets
 build/
 bin/
 target/
-.gradle/
+.buckd/
+.buckversion
 .classpath
 .checkstyle
 .project
 .settings/
 .idea/
+.watchmanconfig
 *.iml
diff --git a/.travis.yml b/.travis.yml
deleted file mode 100644
index 1cf60c0..0000000
--- a/.travis.yml
+++ /dev/null
@@ -1,20 +0,0 @@
-language: java
-jdk:
-  - oraclejdk7
-  - openjdk7
-env:
-  matrix:
-    - API_VERSION=2.8
-    - API_VERSION=2.8.1
-    - API_VERSION=2.8.2
-    - API_VERSION=2.8.3
-    - API_VERSION=2.8.4
-    - API_VERSION=2.8.5
-    - API_VERSION=2.9
-    - API_VERSION=2.9.1
-    - API_VERSION=2.9.3
-    - API_VERSION=2.10
-
-install: true
-
-script: ./gradlew build -PapiVersion=$API_VERSION
diff --git a/BUCK b/BUCK
new file mode 100644
index 0000000..4e69319
--- /dev/null
+++ b/BUCK
@@ -0,0 +1,55 @@
+include_defs('//bucklets/gerrit_plugin.bucklet')
+include_defs('//bucklets/maven_jar.bucklet')
+
+gerrit_plugin(
+  name = 'rabbitmq',
+  srcs = glob(['src/main/java/**/*.java']),
+  resources = glob(['src/main/resources/**/*']),
+  manifest_entries = [
+    'Gerrit-PluginName: rabbitmq',
+    'Gerrit-Module: com.googlesource.gerrit.plugins.rabbitmq.Module',
+    'Implementation-Title: Gerrit rabbitmq plugin',
+    'Implementation-URL: https://github.com/rinrinne/gerrit-rabbitmq-plugin',
+    'Implementation-Vendor: rinrinne',
+  ],
+  deps = [
+    ':amqp-client',
+    ':guice-multibindings',
+  ],
+  provided_deps = [
+    '//lib:gson',
+    '//lib/commons:codec',
+    '//lib/commons:io',
+    '//lib/commons:lang',
+  ],
+)
+
+java_library(
+  name = 'classpath',
+  deps = [':rabbitmq__plugin'],
+)
+
+maven_jar(
+  name = 'amqp-client',
+  id = 'com.rabbitmq:amqp-client:3.5.2',
+  sha1 = '8d10edd29e08f78349bd1da9d18f81c9f8b90567',
+  license = 'MPL1.1',
+  exclude_java_sources = True,
+  visibility = [],
+)
+
+maven_jar(
+  name = 'guice-multibindings',
+  id = 'com.google.inject.extensions:guice-multibindings:4.0-beta5',
+  sha1 = 'f432356db0a167127ffe4a7921238d7205b12682',
+  license = 'Apache2.0',
+  exclude_java_sources = True,
+  exclude = [
+    'META-INF/DEPENDENCIES',
+    'META-INF/LICENSE',
+    'META-INF/NOTICE',
+    'META-INF/maven/com.google.guava/guava/pom.properties',
+    'META-INF/maven/com.google.guava/guava/pom.xml',
+  ],
+  visibility = [],
+)
diff --git a/README.md b/README.md
index 8e71ef5..6b8c33f 100644
--- a/README.md
+++ b/README.md
@@ -21,22 +21,21 @@
 ---------------------
 
 * `linux`
-  * `java-1.7`
-    * `gradle`
+* `java-1.7`
+* `Buck`
 
 Build
 ---------------------
 
-To build plugin with gradle.
+Clone or link this plugin to the plugins directory of Gerrit's source
+tree, and issue the command:
 
-    ./gradlew build
 
-Using another version API
---------------------------
+    buck build plugins/rabbitmq
 
-Now avaliable for Gerrit 2.10 only. If you want to use it on another version of Gerrit, please try the below.
+The output is created in
 
-    ./gradlew build -PapiVersion=2.8
+    buck-out/gen/plugins/rabbitmq/rabbitmq.jar
 
 Reference
 ---------------------
diff --git a/build.gradle b/build.gradle
deleted file mode 100644
index f4eb96d..0000000
--- a/build.gradle
+++ /dev/null
@@ -1,78 +0,0 @@
-task wrapper(type: Wrapper) {
-  gradleVersion = '2.3'
-}
-
-buildscript {
-  repositories {
-    jcenter()
-  }
-  dependencies {
-    classpath 'com.github.jengelman.gradle.plugins:shadow:1.2.1'
-  }
-}
-
-apply plugin: 'java'
-apply plugin: 'eclipse'
-apply plugin: 'idea'
-apply plugin: 'com.github.johnrengelman.shadow'
-
-sourceCompatibility = 1.7
-targetCompatibility = 1.7
-
-group = 'com.googlesource.gerrit.plugins.rabbitmq'
-version = '3.141-SNAPSHOT'
-
-jar {
-  manifest {
-    attributes(
-      'Gerrit-PluginName': project.name,
-      'Gerrit-ApiType': apiType,
-      'Gerrit-ApiVersion': apiVersion,
-      'Gerrit-Module': 'com.googlesource.gerrit.plugins.rabbitmq.Module',
-      'Implementation-Vendor': 'rinrinne',
-      'Implementation-URL': 'https://github.com/rinrinne/gerrit-rabbitmq-plugin',
-      'Implementation-Title': "${apiType} ${project.name}",
-      'Implementation-Version' : version,
-      'Created-By': 'rinrinne (rinrin.ne@gmail.com)'
-    )
-  }
-}
-
-shadowJar {
-  classifier = apiVersion
-  mergeServiceFiles {
-    exclude 'META-INF/*.DSA'
-    exclude 'META-INF/*.RSA'
-  }
-  dependencies {
-    include(dependency('com.rabbitmq:amqp-client'))
-    include(dependency('com.google.inject.extensions:guice-multibindings'))
-  }
-}
-
-repositories {
-  mavenLocal()
-  mavenCentral()
-  maven {
-    name = "Gerrit API repository"
-    url = "https://gerrit-api.storage.googleapis.com/"
-    artifactUrls = [
-      "https://gerrit-api.storage.googleapis.com/release/",
-      "https://gerrit-api.storage.googleapis.com/snapshot/",
-    ]
-  }
-}
-
-dependencies {
-  compile(
-    [group: 'com.google.gerrit', name: "gerrit-${apiType}-api", version: apiVersion],
-    [group: 'com.google.inject.extensions', name: 'guice-multibindings', version: '4.0-beta5'],
-    [group: 'com.google.code.gson', name: 'gson', version: '2.1'],
-    [group: 'commons-lang', name: 'commons-lang', version: '2.5'],
-    [group: 'commons-codec', name: 'commons-codec', version: '1.4'],
-    [group: 'commons-io', name: 'commons-io', version: '1.4'],
-    [group: 'com.rabbitmq', name: 'amqp-client', version: '3.5.0'],
-  )
-}
-
-assemble.dependsOn shadowJar
diff --git a/gradle.properties b/gradle.properties
deleted file mode 100644
index 9d7322f..0000000
--- a/gradle.properties
+++ /dev/null
@@ -1,2 +0,0 @@
-apiType=plugin
-apiVersion=2.12-SNAPSHOT
diff --git a/gradle/wrapper/gradle-wrapper.jar b/gradle/wrapper/gradle-wrapper.jar
deleted file mode 100644
index 3d0dee6..0000000
--- a/gradle/wrapper/gradle-wrapper.jar
+++ /dev/null
Binary files differ
diff --git a/gradle/wrapper/gradle-wrapper.properties b/gradle/wrapper/gradle-wrapper.properties
deleted file mode 100644
index a955c84..0000000
--- a/gradle/wrapper/gradle-wrapper.properties
+++ /dev/null
@@ -1,6 +0,0 @@
-#Tue Feb 17 13:46:55 JST 2015
-distributionBase=GRADLE_USER_HOME
-distributionPath=wrapper/dists
-zipStoreBase=GRADLE_USER_HOME
-zipStorePath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-2.3-bin.zip
diff --git a/gradlew b/gradlew
deleted file mode 100755
index 91a7e26..0000000
--- a/gradlew
+++ /dev/null
@@ -1,164 +0,0 @@
-#!/usr/bin/env bash
-
-##############################################################################
-##
-##  Gradle start up script for UN*X
-##
-##############################################################################
-
-# Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
-DEFAULT_JVM_OPTS=""
-
-APP_NAME="Gradle"
-APP_BASE_NAME=`basename "$0"`
-
-# Use the maximum available, or set MAX_FD != -1 to use that value.
-MAX_FD="maximum"
-
-warn ( ) {
-    echo "$*"
-}
-
-die ( ) {
-    echo
-    echo "$*"
-    echo
-    exit 1
-}
-
-# OS specific support (must be 'true' or 'false').
-cygwin=false
-msys=false
-darwin=false
-case "`uname`" in
-  CYGWIN* )
-    cygwin=true
-    ;;
-  Darwin* )
-    darwin=true
-    ;;
-  MINGW* )
-    msys=true
-    ;;
-esac
-
-# For Cygwin, ensure paths are in UNIX format before anything is touched.
-if $cygwin ; then
-    [ -n "$JAVA_HOME" ] && JAVA_HOME=`cygpath --unix "$JAVA_HOME"`
-fi
-
-# Attempt to set APP_HOME
-# Resolve links: $0 may be a link
-PRG="$0"
-# Need this for relative symlinks.
-while [ -h "$PRG" ] ; do
-    ls=`ls -ld "$PRG"`
-    link=`expr "$ls" : '.*-> \(.*\)$'`
-    if expr "$link" : '/.*' > /dev/null; then
-        PRG="$link"
-    else
-        PRG=`dirname "$PRG"`"/$link"
-    fi
-done
-SAVED="`pwd`"
-cd "`dirname \"$PRG\"`/" >&-
-APP_HOME="`pwd -P`"
-cd "$SAVED" >&-
-
-CLASSPATH=$APP_HOME/gradle/wrapper/gradle-wrapper.jar
-
-# Determine the Java command to use to start the JVM.
-if [ -n "$JAVA_HOME" ] ; then
-    if [ -x "$JAVA_HOME/jre/sh/java" ] ; then
-        # IBM's JDK on AIX uses strange locations for the executables
-        JAVACMD="$JAVA_HOME/jre/sh/java"
-    else
-        JAVACMD="$JAVA_HOME/bin/java"
-    fi
-    if [ ! -x "$JAVACMD" ] ; then
-        die "ERROR: JAVA_HOME is set to an invalid directory: $JAVA_HOME
-
-Please set the JAVA_HOME variable in your environment to match the
-location of your Java installation."
-    fi
-else
-    JAVACMD="java"
-    which java >/dev/null 2>&1 || die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
-
-Please set the JAVA_HOME variable in your environment to match the
-location of your Java installation."
-fi
-
-# Increase the maximum file descriptors if we can.
-if [ "$cygwin" = "false" -a "$darwin" = "false" ] ; then
-    MAX_FD_LIMIT=`ulimit -H -n`
-    if [ $? -eq 0 ] ; then
-        if [ "$MAX_FD" = "maximum" -o "$MAX_FD" = "max" ] ; then
-            MAX_FD="$MAX_FD_LIMIT"
-        fi
-        ulimit -n $MAX_FD
-        if [ $? -ne 0 ] ; then
-            warn "Could not set maximum file descriptor limit: $MAX_FD"
-        fi
-    else
-        warn "Could not query maximum file descriptor limit: $MAX_FD_LIMIT"
-    fi
-fi
-
-# For Darwin, add options to specify how the application appears in the dock
-if $darwin; then
-    GRADLE_OPTS="$GRADLE_OPTS \"-Xdock:name=$APP_NAME\" \"-Xdock:icon=$APP_HOME/media/gradle.icns\""
-fi
-
-# For Cygwin, switch paths to Windows format before running java
-if $cygwin ; then
-    APP_HOME=`cygpath --path --mixed "$APP_HOME"`
-    CLASSPATH=`cygpath --path --mixed "$CLASSPATH"`
-
-    # We build the pattern for arguments to be converted via cygpath
-    ROOTDIRSRAW=`find -L / -maxdepth 1 -mindepth 1 -type d 2>/dev/null`
-    SEP=""
-    for dir in $ROOTDIRSRAW ; do
-        ROOTDIRS="$ROOTDIRS$SEP$dir"
-        SEP="|"
-    done
-    OURCYGPATTERN="(^($ROOTDIRS))"
-    # Add a user-defined pattern to the cygpath arguments
-    if [ "$GRADLE_CYGPATTERN" != "" ] ; then
-        OURCYGPATTERN="$OURCYGPATTERN|($GRADLE_CYGPATTERN)"
-    fi
-    # Now convert the arguments - kludge to limit ourselves to /bin/sh
-    i=0
-    for arg in "$@" ; do
-        CHECK=`echo "$arg"|egrep -c "$OURCYGPATTERN" -`
-        CHECK2=`echo "$arg"|egrep -c "^-"`                                 ### Determine if an option
-
-        if [ $CHECK -ne 0 ] && [ $CHECK2 -eq 0 ] ; then                    ### Added a condition
-            eval `echo args$i`=`cygpath --path --ignore --mixed "$arg"`
-        else
-            eval `echo args$i`="\"$arg\""
-        fi
-        i=$((i+1))
-    done
-    case $i in
-        (0) set -- ;;
-        (1) set -- "$args0" ;;
-        (2) set -- "$args0" "$args1" ;;
-        (3) set -- "$args0" "$args1" "$args2" ;;
-        (4) set -- "$args0" "$args1" "$args2" "$args3" ;;
-        (5) set -- "$args0" "$args1" "$args2" "$args3" "$args4" ;;
-        (6) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" ;;
-        (7) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" ;;
-        (8) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" ;;
-        (9) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" "$args8" ;;
-    esac
-fi
-
-# Split up the JVM_OPTS And GRADLE_OPTS values into an array, following the shell quoting and substitution rules
-function splitJvmOpts() {
-    JVM_OPTS=("$@")
-}
-eval splitJvmOpts $DEFAULT_JVM_OPTS $JAVA_OPTS $GRADLE_OPTS
-JVM_OPTS[${#JVM_OPTS[*]}]="-Dorg.gradle.appname=$APP_BASE_NAME"
-
-exec "$JAVACMD" "${JVM_OPTS[@]}" -classpath "$CLASSPATH" org.gradle.wrapper.GradleWrapperMain "$@"
diff --git a/gradlew.bat b/gradlew.bat
deleted file mode 100644
index aec9973..0000000
--- a/gradlew.bat
+++ /dev/null
@@ -1,90 +0,0 @@
-@if "%DEBUG%" == "" @echo off

-@rem ##########################################################################

-@rem

-@rem  Gradle startup script for Windows

-@rem

-@rem ##########################################################################

-

-@rem Set local scope for the variables with windows NT shell

-if "%OS%"=="Windows_NT" setlocal

-

-@rem Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.

-set DEFAULT_JVM_OPTS=

-

-set DIRNAME=%~dp0

-if "%DIRNAME%" == "" set DIRNAME=.

-set APP_BASE_NAME=%~n0

-set APP_HOME=%DIRNAME%

-

-@rem Find java.exe

-if defined JAVA_HOME goto findJavaFromJavaHome

-

-set JAVA_EXE=java.exe

-%JAVA_EXE% -version >NUL 2>&1

-if "%ERRORLEVEL%" == "0" goto init

-

-echo.

-echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.

-echo.

-echo Please set the JAVA_HOME variable in your environment to match the

-echo location of your Java installation.

-

-goto fail

-

-:findJavaFromJavaHome

-set JAVA_HOME=%JAVA_HOME:"=%

-set JAVA_EXE=%JAVA_HOME%/bin/java.exe

-

-if exist "%JAVA_EXE%" goto init

-

-echo.

-echo ERROR: JAVA_HOME is set to an invalid directory: %JAVA_HOME%

-echo.

-echo Please set the JAVA_HOME variable in your environment to match the

-echo location of your Java installation.

-

-goto fail

-

-:init

-@rem Get command-line arguments, handling Windowz variants

-

-if not "%OS%" == "Windows_NT" goto win9xME_args

-if "%@eval[2+2]" == "4" goto 4NT_args

-

-:win9xME_args

-@rem Slurp the command line arguments.

-set CMD_LINE_ARGS=

-set _SKIP=2

-

-:win9xME_args_slurp

-if "x%~1" == "x" goto execute

-

-set CMD_LINE_ARGS=%*

-goto execute

-

-:4NT_args

-@rem Get arguments from the 4NT Shell from JP Software

-set CMD_LINE_ARGS=%$

-

-:execute

-@rem Setup the command line

-

-set CLASSPATH=%APP_HOME%\gradle\wrapper\gradle-wrapper.jar

-

-@rem Execute Gradle

-"%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -classpath "%CLASSPATH%" org.gradle.wrapper.GradleWrapperMain %CMD_LINE_ARGS%

-

-:end

-@rem End local scope for the variables with windows NT shell

-if "%ERRORLEVEL%"=="0" goto mainEnd

-

-:fail

-rem Set variable GRADLE_EXIT_CONSOLE if you need the _script_ return code instead of

-rem the _cmd.exe /c_ return code!

-if  not "" == "%GRADLE_EXIT_CONSOLE%" exit 1

-exit /b 1

-

-:mainEnd

-if "%OS%"=="Windows_NT" endlocal

-

-:omega

diff --git a/lib/BUCK b/lib/BUCK
new file mode 100644
index 0000000..06f7c02
--- /dev/null
+++ b/lib/BUCK
@@ -0,0 +1,8 @@
+include_defs('//bucklets/maven_jar.bucklet')
+
+maven_jar(
+  name = 'gson',
+  id = 'com.google.code.gson:gson:2.3.1',
+  sha1 = 'ecb6e1f8e4b0e84c4b886c2f14a1500caf309757',
+  license = 'Apache2.0',
+)
diff --git a/lib/commons/BUCK b/lib/commons/BUCK
new file mode 100644
index 0000000..7b7f70f
--- /dev/null
+++ b/lib/commons/BUCK
@@ -0,0 +1,24 @@
+include_defs('//bucklets/maven_jar.bucklet')
+
+maven_jar(
+  name = 'codec',
+  id = 'commons-codec:commons-codec:1.4',
+  sha1 = '4216af16d38465bbab0f3dff8efa14204f7a399a',
+  license = 'Apache2.0',
+  exclude = ['META-INF/LICENSE.txt', 'META-INF/NOTICE.txt'],
+)
+
+maven_jar(
+  name = 'lang',
+  id = 'commons-lang:commons-lang:2.5',
+  sha1 = 'b0236b252e86419eef20c31a44579d2aee2f0a69',
+  license = 'Apache2.0',
+  exclude = ['META-INF/LICENSE.txt', 'META-INF/NOTICE.txt'],
+)
+
+maven_jar(
+  name = 'io',
+  id = 'commons-io:commons-io:1.4',
+  sha1 = 'a8762d07e76cfde2395257a5da47ba7c1dbd3dce',
+  license = 'Apache2.0',
+)
diff --git a/lib/gerrit/BUCK b/lib/gerrit/BUCK
new file mode 100644
index 0000000..85b90a8
--- /dev/null
+++ b/lib/gerrit/BUCK
@@ -0,0 +1,12 @@
+include_defs('//bucklets/maven_jar.bucklet')
+
+VER = '2.12-SNAPSHOT'
+REPO = MAVEN_LOCAL
+
+maven_jar(
+  name = 'plugin-api',
+  id = 'com.google.gerrit:gerrit-plugin-api:' + VER,
+  license = 'Apache2.0',
+  attach_source = False,
+  repository = REPO,
+)
diff --git a/settings.gradle b/settings.gradle
deleted file mode 100644
index 1adba7a..0000000
--- a/settings.gradle
+++ /dev/null
@@ -1 +0,0 @@
-rootProject.name = 'rabbitmq'
diff --git a/src/main/java/com/googlesource/gerrit/plugins/rabbitmq/Manager.java b/src/main/java/com/googlesource/gerrit/plugins/rabbitmq/Manager.java
index 84d47cb..99804d4 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/rabbitmq/Manager.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/rabbitmq/Manager.java
@@ -117,7 +117,7 @@
     Properties base = propFactory.create(pluginDataDir.resolve(pluginName + FILE_EXT));
     base.load();
 
-    // Load site
+    // Load sites
     try (DirectoryStream<Path> ds = Files.newDirectoryStream(pluginDataDir.resolve(SITE_DIR), "*" + FILE_EXT)) {
       for (Path configFile : ds) {
         Properties site = propFactory.create(configFile);
@@ -128,6 +128,10 @@
     } catch (IOException iex) {
       LOGGER.warn(iex.getMessage());
     }
+    if (propList.isEmpty()) {
+      LOGGER.warn("No site configs found. Using base config only!");
+      propList.add(base);
+    }
     return propList;
   }
 }
diff --git a/src/main/java/com/googlesource/gerrit/plugins/rabbitmq/config/AMQProperties.java b/src/main/java/com/googlesource/gerrit/plugins/rabbitmq/config/AMQProperties.java
index 0fd3a88..fd2264f 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/rabbitmq/config/AMQProperties.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/rabbitmq/config/AMQProperties.java
@@ -14,6 +14,7 @@
 
 package com.googlesource.gerrit.plugins.rabbitmq.config;
 
+import com.google.gerrit.common.TimeUtil;
 import com.googlesource.gerrit.plugins.rabbitmq.annotation.MessageHeader;
 import com.googlesource.gerrit.plugins.rabbitmq.config.section.Message;
 import com.googlesource.gerrit.plugins.rabbitmq.config.section.Section;
@@ -24,6 +25,7 @@
 import org.slf4j.LoggerFactory;
 
 import java.lang.reflect.Field;
+import java.util.Date;
 import java.util.HashMap;
 import java.util.Map;
 
@@ -34,54 +36,55 @@
 
   private static final Logger LOGGER = LoggerFactory.getLogger(AMQProperties.class);
 
-  private final PluginProperties properties;
-  private AMQP.BasicProperties amqpProperties;
+  private final Message message;
+  private final Map<String, Object> headers;
 
   public AMQProperties(PluginProperties properties) {
-    this.properties = properties;
-  }
-
-  public AMQP.BasicProperties getBasicProperties() {
-    if (amqpProperties == null) {
-      Map<String, Object> headers = new HashMap<>();
-      for (Section section : properties.getSections()) {
-        for (Field f : section.getClass().getFields()) {
-          if (f.isAnnotationPresent(MessageHeader.class)) {
-            MessageHeader mh = f.getAnnotation(MessageHeader.class);
-            try {
-              switch(f.getType().getSimpleName()) {
-                case "String":
-                  headers.put(mh.value(), f.get(section).toString());
-                  break;
-                case "Integer":
-                  headers.put(mh.value(), f.getInt(section));
-                  break;
-                case "Long":
-                  headers.put(mh.value(), f.getLong(section));
-                  break;
-                case "Boolean":
-                  headers.put(mh.value(), f.getBoolean(section));
-                  break;
-                default:
-                  break;
-              }
-            } catch (Exception ex) {
-              LOGGER.info(ex.getMessage());
+    this.message = properties.getSection(Message.class);
+    this.headers = new HashMap<>();
+    for (Section section : properties.getSections()) {
+      for (Field f : section.getClass().getFields()) {
+        if (f.isAnnotationPresent(MessageHeader.class)) {
+          MessageHeader mh = f.getAnnotation(MessageHeader.class);
+          try {
+            Object value = f.get(section);
+            if (value == null) {
+              continue;
             }
+            switch(f.getType().getSimpleName()) {
+              case "String":
+                headers.put(mh.value(), value.toString());
+                break;
+              case "Integer":
+                headers.put(mh.value(), Integer.valueOf(value.toString()));
+                break;
+              case "Long":
+                headers.put(mh.value(), Long.valueOf(value.toString()));
+                break;
+              case "Boolean":
+                headers.put(mh.value(), Boolean.valueOf(value.toString()));
+                break;
+              default:
+                break;
+            }
+          } catch (IllegalAccessException | IllegalArgumentException ex) {
+            LOGGER.warn("Cannot access field {}. Cause: {}",
+                f.getName(), ex.getMessage());
           }
         }
       }
-      Message message = properties.getSection(Message.class);
-      AMQP.BasicProperties.Builder builder = new AMQP.BasicProperties.Builder();
-      builder.appId(EVENT_APPID);
-      builder.contentEncoding(CharEncoding.UTF_8);
-      builder.contentType(CONTENT_TYPE_JSON);
-      builder.deliveryMode(message.deliveryMode);
-      builder.priority(message.priority);
-      builder.headers(headers);
-
-      amqpProperties = builder.build();
     }
-    return amqpProperties;
+  }
+
+  public AMQP.BasicProperties getBasicProperties() {
+    return new AMQP.BasicProperties.Builder()
+      .appId(EVENT_APPID)
+      .contentEncoding(CharEncoding.UTF_8)
+      .contentType(CONTENT_TYPE_JSON)
+      .deliveryMode(message.deliveryMode)
+      .priority(message.priority)
+      .headers(headers)
+      .timestamp(new Date(TimeUtil.nowMs()))
+      .build();
   }
 }
diff --git a/src/main/java/com/googlesource/gerrit/plugins/rabbitmq/config/PluginProperties.java b/src/main/java/com/googlesource/gerrit/plugins/rabbitmq/config/PluginProperties.java
index 9c978b2..36ba106 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/rabbitmq/config/PluginProperties.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/rabbitmq/config/PluginProperties.java
@@ -115,7 +115,10 @@
   @Override
   public String getName() {
     if (propertiesFile != null) {
-      return FilenameUtils.removeExtension(propertiesFile.getFileName().toString());
+      Path path = propertiesFile.getFileName();
+      if (path != null) {
+        return FilenameUtils.removeExtension(path.toString());
+      }
     }
     return null;
   }
@@ -136,7 +139,7 @@
   }
 
   public String getGerritFrontUrl() {
-    Gerrit gerrit = (Gerrit) getSection(Gerrit.class);
+    Gerrit gerrit = getSection(Gerrit.class);
     if (gerrit != null) {
       return gerrit.canonicalWebUrl;
     }
@@ -144,7 +147,7 @@
   }
 
   public boolean hasListenAs() {
-    Gerrit gerrit = (Gerrit) getSection(Gerrit.class);
+    Gerrit gerrit = getSection(Gerrit.class);
     if (gerrit != null) {
       return gerrit.listenAs.isEmpty();
     }
@@ -152,7 +155,7 @@
   }
 
   public String getListenAs() {
-    Gerrit gerrit = (Gerrit) getSection(Gerrit.class);
+    Gerrit gerrit = getSection(Gerrit.class);
     if (gerrit != null) {
       return gerrit.listenAs;
     }
@@ -160,7 +163,7 @@
   }
 
   public String getGerritVersion() {
-    Gerrit gerrit = (Gerrit) getSection(Gerrit.class);
+    Gerrit gerrit = getSection(Gerrit.class);
     if (gerrit != null) {
       return gerrit.version;
     }
@@ -168,13 +171,14 @@
   }
 
   public int getConnectionMonitorInterval() {
-    Monitor monitor = (Monitor) getSection(Monitor.class);
+    Monitor monitor = getSection(Monitor.class);
     if (monitor != null && monitor.interval < MINIMUM_CONNECTION_MONITOR_INTERVAL) {
       return monitor.interval;
     }
     return MINIMUM_CONNECTION_MONITOR_INTERVAL;
   }
 
+  @Override
   public AMQProperties getAMQProperties() {
     if (amqProperties == null) {
       amqProperties = new AMQProperties(this);
diff --git a/src/main/java/com/googlesource/gerrit/plugins/rabbitmq/config/section/Sections.java b/src/main/java/com/googlesource/gerrit/plugins/rabbitmq/config/section/Sections.java
index 263f8ba..759ef03 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/rabbitmq/config/section/Sections.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/rabbitmq/config/section/Sections.java
@@ -39,17 +39,18 @@
           Default a = f.getAnnotation(Default.class);
           Class<?> type = f.getType();
           if (type == String.class) {
-            f.set(section, new String(a.value()));
+            f.set(section, a.value());
           } else if (type == Integer.class) {
-            f.set(section, new Integer(a.value()));
+            f.set(section, Integer.valueOf(a.value()));
           } else if (type == Long.class) {
-            f.set(section, new Long(a.value()));
+            f.set(section, Long.valueOf(a.value()));
           } else if (type == Boolean.class) {
-            f.set(section, new Boolean(a.value()));
+            f.set(section, Boolean.valueOf(a.value()));
           }
         }
-      } catch (Exception ex) {
-        LOGGER.warn("Exception during initialize: {}", f.getName());
+      } catch (IllegalAccessException ex) {
+        LOGGER.warn("Cannot access field {}. Cause: {}",
+            f.getName(), ex.getMessage());
       }
     }
     return section;
@@ -76,9 +77,9 @@
             config.setBoolean(getName(section), null, f.getName(), Boolean.class.cast(obj));
           }
         }
-      } catch (Exception ex) {
-        LOGGER.warn("Exception during toConfig: {}", f.getName());
-        LOGGER.info("{}", ex.getMessage());
+      } catch (IllegalAccessException ex) {
+        LOGGER.warn("Cannot access field {}. Cause: {}",
+            f.getName(), ex.getMessage());
       }
     }
     return config;
@@ -95,17 +96,18 @@
             if (names.contains(f.getName())) {
               Class<?> type = f.getType();
               if (type == String.class) {
-                f.set(section, new String(config.getString(getName(section), null, f.getName())));
+                f.set(section, config.getString(getName(section), null, f.getName()));
               } else if (type == Integer.class) {
-                f.set(section, new Integer(config.getInt(getName(section), null, f.getName(), 0)));
+                f.set(section, config.getInt(getName(section), null, f.getName(), 0));
               } else if (type == Long.class) {
-                f.set(section, new Long(config.getLong(getName(section), null, f.getName(), 0)));
+                f.set(section, config.getLong(getName(section), null, f.getName(), 0));
               } else if (type == Boolean.class) {
-                f.set(section, new Boolean(config.getBoolean(getName(section), null, f.getName(), false)));
+                f.set(section, config.getBoolean(getName(section), null, f.getName(), false));
               }
             }
-          } catch (Exception ex) {
-            LOGGER.warn("Exception during fromConfig: {}", f.getName());
+          } catch (IllegalAccessException ex) {
+            LOGGER.warn("Cannot access field {}. Cause: {}",
+                f.getName(), ex.getMessage());
           }
         }
       }
@@ -131,9 +133,9 @@
             f.set(section, val);
           }
         }
-      } catch (Exception ex) {
-        LOGGER.warn("Exception during normalize: {}", f.getName());
-        LOGGER.info("{}", ex.getMessage());
+      } catch (IllegalAccessException ex) {
+        LOGGER.warn("Cannot access field {}. Cause: {}",
+            f.getName(), ex.getMessage());
       }
     }
     return section;
diff --git a/src/main/java/com/googlesource/gerrit/plugins/rabbitmq/session/type/AMQPSession.java b/src/main/java/com/googlesource/gerrit/plugins/rabbitmq/session/type/AMQPSession.java
index f7dfba6..1f9b7e3 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/rabbitmq/session/type/AMQPSession.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/rabbitmq/session/type/AMQPSession.java
@@ -34,6 +34,10 @@
 
 import java.io.IOException;
 import java.net.URISyntaxException;
+import java.security.KeyManagementException;
+import java.security.NoSuchAlgorithmException;
+import java.util.concurrent.TimeoutException;
+import java.util.concurrent.atomic.AtomicInteger;
 
 public final class AMQPSession implements Session {
 
@@ -58,9 +62,10 @@
           if (clazz == Channel.class) {
             Channel ch = Channel.class.cast(obj);
             if (cause.isInitiatedByApplication()) {
-              LOGGER.info(MSG("Channel #{} closed."), ch.getChannelNumber());
+              LOGGER.info(MSG("Channel #{} closed by application."), ch.getChannelNumber());
             } else {
-              LOGGER.info(MSG("Channel #{} suddenly closed."), ch.getChannelNumber());
+              LOGGER.warn(MSG("Channel #{} closed. Cause: {}"),
+                ch.getChannelNumber(), cause.getMessage());
             }
             if (ch.equals(AMQPSession.this.channel)) {
               AMQPSession.this.channel = null;
@@ -68,9 +73,9 @@
           } else if (clazz == Connection.class) {
             Connection conn = Connection.class.cast(obj);
             if (cause.isInitiatedByApplication()) {
-              LOGGER.info(MSG("Connection closed."));
+              LOGGER.info(MSG("Connection closed by application."));
             } else {
-              LOGGER.info(MSG("Connection suddenly closed."));
+              LOGGER.warn(MSG("Connection closed. Cause: {}"), cause.getMessage());
             }
             if (conn.equals(AMQPSession.this.connection)) {
               AMQPSession.this.connection = null;
@@ -85,8 +90,8 @@
   private final Properties properties;
   private volatile Connection connection;
   private volatile Channel channel;
-  private volatile int failureCount = 0;
 
+  private final AtomicInteger failureCount = new AtomicInteger(0);
   private final ShutdownListener connectionListener = new ShutdownListenerImpl(Connection.class);
   private final ShutdownListener channelListener = new ShutdownListenerImpl(Channel.class);
 
@@ -114,13 +119,13 @@
       try {
         ch = connection.createChannel();
         ch.addShutdownListener(channelListener);
-        failureCount = 0;
+        failureCount.set(0);
         LOGGER.info(MSG("Channel #{} opened."), ch.getChannelNumber());
-      } catch (Exception ex) {
-        LOGGER.warn(MSG("Failed to open channel."));
-        failureCount++;
+      } catch (IOException ex) {
+        LOGGER.error(MSG("Failed to open channel."), ex);
+        failureCount.incrementAndGet();
       }
-      if (failureCount > properties.getSection(Monitor.class).failureCount) {
+      if (failureCount.get() > properties.getSection(Monitor.class).failureCount) {
         LOGGER.warn("Connection has something wrong. So will be disconnected.");
         disconnect();
       }
@@ -153,9 +158,9 @@
     } catch (URISyntaxException ex) {
       LOGGER.error(MSG("URI syntax error: {}"), amqp.uri);
     } catch (IOException ex) {
-      LOGGER.error(MSG("Connection cannot be opened."));
-    } catch (Exception ex) {
-      LOGGER.warn(MSG("Connection has something error. it will be disposed."), ex);
+      LOGGER.error(MSG("Connection cannot be opened."), ex);
+    } catch (KeyManagementException | NoSuchAlgorithmException ex) {
+      LOGGER.error(MSG("Security error when opening connection."), ex);
     }
   }
 
@@ -164,22 +169,22 @@
     LOGGER.info(MSG("Disconnecting..."));
     try {
       if (channel != null) {
-        LOGGER.info(MSG("Close Channel #{}..."), channel.getChannelNumber());
+        LOGGER.info(MSG("Closing Channel #{}..."), channel.getChannelNumber());
         channel.close();
       }
-    } catch (Exception ex) {
-      LOGGER.warn(MSG("Error when close channel.") , ex);
+    } catch (IOException | TimeoutException ex) {
+      LOGGER.error(MSG("Error when closing channel."), ex);
     } finally {
       channel = null;
     }
 
     try {
       if (connection != null) {
-        LOGGER.info(MSG("Close Connection..."));
+        LOGGER.info(MSG("Closing Connection..."));
         connection.close();
       }
-    } catch (Exception ex) {
-      LOGGER.warn(MSG("Error when close connection.") , ex);
+    } catch (IOException ex) {
+      LOGGER.error(MSG("Error when closing connection."), ex);
     } finally {
       connection = null;
     }
@@ -194,12 +199,12 @@
       Message message = properties.getSection(Message.class);
       Exchange exchange = properties.getSection(Exchange.class);
       try {
-        LOGGER.debug(MSG("Send message."));
+        LOGGER.debug(MSG("Sending message."));
         channel.basicPublish(exchange.name, message.routingKey,
             properties.getAMQProperties().getBasicProperties(),
             messageBody.getBytes(CharEncoding.UTF_8));
-      } catch (Exception ex) {
-        LOGGER.warn(MSG("Error when sending meessage."), ex);
+      } catch (IOException ex) {
+        LOGGER.error(MSG("Error when sending meessage."), ex);
       }
     }
   }
diff --git a/src/main/java/com/googlesource/gerrit/plugins/rabbitmq/solver/version/V1.java b/src/main/java/com/googlesource/gerrit/plugins/rabbitmq/solver/version/V1.java
index e6f54a3..0b91423 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/rabbitmq/solver/version/V1.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/rabbitmq/solver/version/V1.java
@@ -26,6 +26,7 @@
 import org.slf4j.LoggerFactory;
 
 import java.io.File;
+import java.io.IOException;
 import java.nio.file.Files;
 import java.nio.file.Path;
 
@@ -55,17 +56,23 @@
    * new : data/rabbitmq/rabbitmq.config
    *       data/rabbitmq/site/default.config
    */
+  @Override
   public void solve() {
     try {
       Path oldFile = etcDir.resolve(pluginName + FILE_EXT);
       Path newFile = pluginDataDir.resolve(pluginName + FILE_EXT);
       Path siteDir = pluginDataDir.resolve(SITE_DIR);
+      Path defaultSiteFile = siteDir.resolve(DEFAULT_SITE_NAME + FILE_EXT);
 
       Files.createDirectories(siteDir);
-      Files.move(oldFile, newFile);
-      Files.createFile(siteDir.resolve(DEFAULT_SITE_NAME + FILE_EXT));
-    } catch (Exception ex) {
-      LOGGER.info(ex.getMessage());
+      if (oldFile.toFile().exists()) {
+        Files.move(oldFile, newFile);
+      }
+      if (!defaultSiteFile.toFile().exists()) {
+        Files.createFile(defaultSiteFile);
+      }
+    } catch (IOException ex) {
+      LOGGER.error("Failed to initialize plugin configuration", ex);
     }
   }
 }
diff --git a/src/main/resources/Documentation/build.md b/src/main/resources/Documentation/build.md
new file mode 100644
index 0000000..38c3bb5
--- /dev/null
+++ b/src/main/resources/Documentation/build.md
@@ -0,0 +1,73 @@
+Build
+=====
+
+This plugin is built with Buck.
+
+Two build modes are supported: Standalone and in Gerrit tree. Standalone
+build mode is recommended, as this mode doesn't require local Gerrit
+tree to exist.
+
+Build standalone
+----------------
+
+Clone bucklets library:
+
+```
+  git clone https://gerrit.googlesource.com/bucklets
+
+```
+and link it to rabbitmq directory:
+
+```
+  cd rabbitmq && ln -s ../bucklets .
+```
+
+Add link to the .buckversion file:
+
+```
+  cd rabbitmq && ln -s bucklets/buckversion .buckversion
+```
+
+Add link to the .watchmanconfig file:
+
+```
+  cd rabbitmq && ln -s bucklets/watchmanconfig .watchmanconfig
+```
+
+To build the plugin, issue the following command:
+
+
+```
+  buck build plugin
+```
+
+The output is created in
+
+```
+  buck-out/gen/rabbitmq.jar
+```
+
+Build in Gerrit tree
+--------------------
+
+Clone or link this plugin to the plugins directory of Gerrit's source
+tree, and issue the command:
+
+```
+  buck build plugins/rabbitmq
+```
+
+The output is created in
+
+```
+  buck-out/gen/plugins/rabbitmq/rabbitmq.jar
+```
+
+This project can be imported into the Eclipse IDE:
+
+```
+  ./tools/eclipse/project.py
+```
+
+How to build the Gerrit Plugin API is described in the [Gerrit
+documentation](../../../Documentation/dev-buck.html#_extension_and_plugin_api_jar_files).