RegexpOnFilename: Add a new rule to detect if there are any sync conflict files

Fails if there there are any Syncthing or Dropbox sync conflicts on any *.java file.

README.md

@@ -219,6 +219,7 @@ Rule|Level|Source|Enabled|Suppressable
 [Regexp](#regexp)|unspecified|checkstyle||
 [RegexpHeader](#regexpheader)|unspecified|checkstyle||
 [RegexpMultiline](#regexpmultiline)|unspecified|checkstyle||
+[RegexpOnFilename](#regexponfilename)|layout|checkstyle|Yes|
 [RegexpOnFilename](#regexponfilename)|unspecified|checkstyle||
 [RegexpSingleline](#regexpsingleline)|unspecified|checkstyle||
 [RegexpSinglelineJava](#regexpsinglelinejava)|unspecified|checkstyle||
@@ -274,6 +275,22 @@ The following is a list of each of the checks and the expectations each has on y
 
 Rules are listed in alphabetical order.
 
+#### [RegexpOnFilename](http://checkstyle.sourceforge.net/config_regexp.html#RegexpOnFilename)
+
+Checks for the existence of forbidden java file names.
+
+File names are forbidden if they match the pattern `(.sync-conflict-| conflicted copy )`.
+
+N.B. only `*.java` files are checked.
+
+This check is intended to detect Syncthing and Dropbox conflict files.
+
+e.g.
+````
+DataClass (Bob's conflicted copy 2017-03-11).java
+DataClass.sync-conflict-20170311-1648.java
+````
+
 #### [AbbreviationAsWordInName](http://checkstyle.sourceforge.net/config_naming.html#AbbreviationAsWordInName)
 
 Enforces proper `CamelCase` and avoids sequences of consecutive uppercase characters in identifiers. Does not apply to @Overridden methods.

builder/src/main/resources/application.yml

@@ -12,6 +12,16 @@ template:
     readme-template: builder/src/main/resources/README-template.md
     readme-fragments: builder/src/main/resources/rules
 rules:
+    -
+        name: RegexpOnFilename
+        parent: CHECKER
+        level: LAYOUT
+        enabled: true
+        source: CHECKSTYLE
+        uri: http://checkstyle.sourceforge.net/config_regexp.html#RegexpOnFilename
+        properties:
+            fileNamePattern: "(.sync-conflict-| conflicted copy )"
+            match: true
     -
         name: AbbreviationAsWordInName
         parent: TREEWALKER

builder/src/main/resources/rules/RegexpOnFilename.md

@@ -0,0 +1,15 @@
+
+Checks for the existence of forbidden java file names.
+
+File names are forbidden if they match the pattern `(.sync-conflict-| conflicted copy )`.
+
+N.B. only `*.java` files are checked.
+
+This check is intended to detect Syncthing and Dropbox conflict files.
+
+e.g.
+````
+DataClass (Bob's conflicted copy 2017-03-11).java
+DataClass.sync-conflict-20170311-1648.java
+````
+

ruleset/src/main/resources/net/kemitix/checkstyle-1-layout.xml

@@ -4,6 +4,10 @@
         "http://www.puppycrawl.com/dtds/configuration_1_3.dtd">
 <module name="Checker">
 
+    <module name="RegexpOnFilename">
+    <property name="fileNamePattern" value="(.sync-conflict-| conflicted copy )"/>
+<property name="match" value="true"/>
+</module>
 <module name="FileTabCharacter"/>
 <module name="Header">
     <property name="fileExtensions" value="java"/>

ruleset/src/main/resources/net/kemitix/checkstyle-2-naming.xml

@@ -4,6 +4,10 @@
         "http://www.puppycrawl.com/dtds/configuration_1_3.dtd">
 <module name="Checker">
 
+    <module name="RegexpOnFilename">
+    <property name="fileNamePattern" value="(.sync-conflict-| conflicted copy )"/>
+<property name="match" value="true"/>
+</module>
 <module name="FileTabCharacter"/>
 <module name="Header">
     <property name="fileExtensions" value="java"/>

ruleset/src/main/resources/net/kemitix/checkstyle-3-javadoc.xml

@@ -4,6 +4,10 @@
         "http://www.puppycrawl.com/dtds/configuration_1_3.dtd">
 <module name="Checker">
 
+    <module name="RegexpOnFilename">
+    <property name="fileNamePattern" value="(.sync-conflict-| conflicted copy )"/>
+<property name="match" value="true"/>
+</module>
 <module name="FileTabCharacter"/>
 <module name="Header">
     <property name="fileExtensions" value="java"/>

ruleset/src/main/resources/net/kemitix/checkstyle-4-tweaks.xml

@@ -4,6 +4,10 @@
         "http://www.puppycrawl.com/dtds/configuration_1_3.dtd">
 <module name="Checker">
 
+    <module name="RegexpOnFilename">
+    <property name="fileNamePattern" value="(.sync-conflict-| conflicted copy )"/>
+<property name="match" value="true"/>
+</module>
 <module name="FileTabCharacter"/>
 <module name="Header">
     <property name="fileExtensions" value="java"/>

ruleset/src/main/resources/net/kemitix/checkstyle-5-complexity.xml

@@ -4,6 +4,10 @@
         "http://www.puppycrawl.com/dtds/configuration_1_3.dtd">
 <module name="Checker">
 
+    <module name="RegexpOnFilename">
+    <property name="fileNamePattern" value="(.sync-conflict-| conflicted copy )"/>
+<property name="match" value="true"/>
+</module>
 <module name="FileLength"/>
 <module name="FileTabCharacter"/>
 <module name="Header">