Regex pattern used for parsing the CruiseControl command output is th…

…readsafe (according to Javadoc), so I am making the Pattern a final static variable to try to improve the performance a bit more.

src/main/java/hudson/scm/SurroundSCMChangeLogParser.java

@@ -10,13 +10,10 @@
 
 public class SurroundSCMChangeLogParser extends ChangeLogParser {
 
-  /**
-   * Standard format for a cruisecontrol output is:
-   * {@code <Mainline/Repository/Path/To/File><Filename.txt><21><Check in><20161103144114><Comment for the action><LastName, FirstName><email@address.com> }
-   */
-  private Pattern changeRegex = null;
   private final static String CC_LINE_PATTERN = "<(.*)><(.*)><(.*)><(.*)><(.*)><(.*)><(.*)><(.*)>";
 
+  private final static Pattern CRUISECONTROL_PATTERN = Pattern.compile(CC_LINE_PATTERN);
+
   /**
    *  Parses the Surround SCM changelogFile, which is generated by the Surround SCM CLI's cruisecontrol command.
    * {@inheritDoc}
@@ -25,7 +22,6 @@ public class SurroundSCMChangeLogParser extends ChangeLogParser {
   public ChangeLogSet<? extends Entry> parse(Run build, RepositoryBrowser<?> browser, File changelogFile) {
     //open the changelog File
     SurroundSCMChangeLogSet cls = new SurroundSCMChangeLogSet(build, browser);
-    changeRegex = Pattern.compile(CC_LINE_PATTERN);
     commonParseChangeLog(cls, changelogFile);
     return cls;
   }
@@ -36,17 +32,23 @@ public ChangeLogSet<? extends Entry> parse(AbstractBuild build,
                                              File changelogFile) {
     //open the changelog File
     SurroundSCMChangeLogSet cls = new SurroundSCMChangeLogSet(build);
-    changeRegex = Pattern.compile(CC_LINE_PATTERN);
     commonParseChangeLog(cls, changelogFile);
 
     return cls;
   }
 
-  public void commonParseChangeLog(SurroundSCMChangeLogSet cls, File changelogFile) {
+  /**
+   * Handles the dirty work of actually parsing the changelog file.
+   *
+   * @param cls           What changelogset to add newly parsed entries too.
+   * @param changelogFile What changelog file to use as a source for the parsing.
+   */
+  private void commonParseChangeLog(SurroundSCMChangeLogSet cls, File changelogFile) {
     String line;
     BufferedReader br = null;
 
-    InputStreamReader is = null;
+    InputStreamReader is;
+
     try{
       is = new InputStreamReader(new FileInputStream(changelogFile), "UTF-8");
 
@@ -79,11 +81,16 @@ public void commonParseChangeLog(SurroundSCMChangeLogSet cls, File changelogFile
      * @param cls               SurroundSCMChangeLogSet this entry will be added to.
      * @param cruiseControlLine Line to parse
      * @return  Returns a new {@link hudson.scm.SurroundSCMChangeLogSet.SurroundSCMChangeLogSetEntry} created based on the
-     *          passed in line.
+     *          passed in line.  This could return a 'null' result if we fail to parse the line.
      */
-  public SurroundSCMChangeLogSet.SurroundSCMChangeLogSetEntry parseCCLine(SurroundSCMChangeLogSet cls, String cruiseControlLine ) {
-    Matcher changeMatcher = changeRegex.matcher(cruiseControlLine);
-
+  private SurroundSCMChangeLogSet.SurroundSCMChangeLogSetEntry parseCCLine(SurroundSCMChangeLogSet cls, String cruiseControlLine ) {
+    Matcher changeMatcher = CRUISECONTROL_PATTERN.matcher(cruiseControlLine);
+
+    // The SSCM 'cruisecontrol' output is supposed to output 8 blocks of "<....>" per line.  However, due to a defect
+    // (which will hopefully be fixed soon) there is a possibility that the contents of hte "<...>" block could themselves
+    // contain "<>" characters.  This breaks the parsing of the line and could result in garbage output.
+    // To try to address that situation in a small way we are going to check to make sure we found exactly 8 'groups'.
+    // If we found more // less then we will consider it a parsing failure, and return a 'null' entry.
     if(changeMatcher.find() && changeMatcher.groupCount() == 8) {
       String repository = changeMatcher.group(1);
       String filename = changeMatcher.group(2);