Added logs to git plugin

src/main/java/hudson/plugins/git/GitSCM.java

@@ -699,7 +699,7 @@
         // Poll for changes. Are there any unbuilt revisions that Jenkins ought to build ?
 
         listener.getLogger().println("Using strategy: " + getBuildChooser().getDisplayName());
-
+        LOGGER.log(Level.FINEST, "Setting remote url: ");
         final Run lastBuild = project.getLastBuild();
         if (lastBuild == null) {
             // If we've never been built before, well, gotta build!
@@ -786,7 +786,7 @@
         }
 
         final Node node = GitUtils.workspaceToNode(workspace);
         final EnvVars environment = project instanceof AbstractProject ? GitUtils.getPollEnvironment((AbstractProject) project, workspace, launcher, listener) : project.getEnvironment(node, listener);
 
         FilePath workingDirectory = workingDirectory(project,workspace,environment,listener);
 
@@ -924,6 +924,7 @@
                 listener.getLogger().println("No credentials specified");
             } else {
                 String url = getParameterString(uc.getUrl(), environment);
+
                 StandardUsernameCredentials credentials = lookupScanCredentials(build, url, ucCredentialsId);
                 if (credentials != null) {
                     c.addCredentials(url, credentials);
@@ -984,18 +985,27 @@
         for (URIish url : remoteRepository.getURIs()) {
             try {
                 if (first) {
+                    LOGGER.log(Level.FINEST, "Setting remote url: ", url.toPrivateASCIIString());
                     git.setRemoteUrl(remoteRepository.getName(), url.toPrivateASCIIString());
                     first = false;
                 } else {
+                    LOGGER.log(Level.FINEST, "Adding remote url: ", url.toPrivateASCIIString());
                     git.addRemoteUrl(remoteRepository.getName(), url.toPrivateASCIIString());
                 }
 
-                FetchCommand fetch = git.fetch_().from(url, remoteRepository.getFetchRefSpecs());
+                FetchCommand fetch = git.fetch_();
+                if(fetch instanceof CliGitAPIImpl) {
+                    LOGGER.log(Level.FINEST, "Instance of CliGitAPIImpl ");
+                } else {
+                    LOGGER.log(Level.FINEST, "Instance of JGitAPIImpl ");
+                }
+                fetch.from(url, remoteRepository.getFetchRefSpecs());
                 for (GitSCMExtension extension : extensions) {
                     extension.decorateFetchCommand(this, run, git, listener, fetch);
                 }
                 fetch.execute();
             } catch (GitException ex) {
+                ex.printStackTrace();
                 throw new GitException("Failed to fetch from "+url.toString(), ex);
             }
         }
@@ -1177,7 +1187,7 @@
             log.println("Multiple candidate revisions");
             if (checkForMultipleRevisions) {
                 Job<?, ?> job = build.getParent();
                 if (job instanceof AbstractProject) {
                     AbstractProject project = (AbstractProject) job;
                     if (!project.isDisabled()) {
                         log.println("Scheduling another build to catch up with " + project.getFullDisplayName());
@@ -1242,126 +1252,127 @@
             } catch (GitException ex) {
                 /* Allow retry by throwing AbortException instead of
                  * GitException. See JENKINS-20531. */
-                ex.printStackTrace(listener.error("Error fetching remote repo '" + remoteRepository.getName() + "'"));
+                //ex.printStackTrace(listener.error("Error fetching remote repo '" + remoteRepository.getName() + "'"));
+                ex.printStackTrace();
                 throw new AbortException("Error fetching remote repo '" + remoteRepository.getName() + "'");
             }
         }
     }
 
     private boolean determineSecondFetch(CloneOption option, @NonNull RemoteConfig rc) {
         List<RefSpec> initialFetchRefSpecs = rc.getFetchRefSpecs();
         boolean isDefaultRefspec = true; // default refspec is any refspec with "refs/heads/" mapping
         boolean removeSecondFetch = true;
         if (initialFetchRefSpecs != null) {
             for (RefSpec ref : initialFetchRefSpecs) {
                 if (!ref.toString().contains("refs/heads")) {
                     isDefaultRefspec = false; // if refspec is not of default type, preserve second fetch
                 }
             }
             if (option == null) {
                 removeSecondFetch = isDefaultRefspec;
             } else {
                 if (option.isHonorRefspec()) {
                     removeSecondFetch = true; // avoid second fetch call if honor refspec is enabled
                 } else {
                     removeSecondFetch = isDefaultRefspec;
                 }
             }
         }
         // if initial fetch refspec contains "refs/heads/*" (default refspec), ignore the second fetch call
         return removeSecondFetch;
     }
 
     @Override
     public void checkout(Run<?, ?> build, Launcher launcher, FilePath workspace, TaskListener listener, File changelogFile, SCMRevisionState baseline)
             throws IOException, InterruptedException {
 
         if (!ALLOW_LOCAL_CHECKOUT && !workspace.isRemote()) {
             abortIfSourceIsLocal();
         }
 
         if (VERBOSE)
             listener.getLogger().println("Using checkout strategy: " + getBuildChooser().getDisplayName());
 
         BuildData previousBuildData = getBuildData(build.getPreviousBuild());   // read only
         BuildData buildData = copyBuildData(build.getPreviousBuild());
 
         if (VERBOSE && buildData.lastBuild != null) {
             listener.getLogger().println("Last Built Revision: " + buildData.lastBuild.revision);
         }
 
         EnvVars environment = build.getEnvironment(listener);
         GitClient git = createClient(listener, environment, build, workspace);
 
         if (launcher instanceof Launcher.DecoratedLauncher) {
             // We cannot check for git instanceof CliGitAPIImpl vs. JGitAPIImpl here since (when running on an agent) we will actually have a RemoteGitImpl which is opaque.
             listener.getLogger().println("Warning: JENKINS-30600: special launcher " + launcher + " will be ignored (a typical symptom is the Git executable not being run inside a designated container)");
         }
 
         for (GitSCMExtension ext : extensions) {
             ext.beforeCheckout(this, build, git, listener);
         }
 
         retrieveChanges(build, git, listener);
         Build revToBuild = determineRevisionToBuild(build, buildData, environment, git, listener);
 
         // Track whether we're trying to add a duplicate BuildData, now that it's been updated with
         // revision info for this build etc. The default assumption is that it's a duplicate.
         boolean buildDataAlreadyPresent = false;
         List<BuildData> actions = build.getActions(BuildData.class);
         for (BuildData d: actions)  {
             if (d.similarTo(buildData)) {
                 buildDataAlreadyPresent = true;
                 break;
             }
         }
         if (!actions.isEmpty()) {
             buildData.setIndex(actions.size()+1);
         }
 
         // If the BuildData is not already attached to this build, add it to the build and mark that
         // it wasn't already present, so that we add the GitTagAction and changelog after the checkout
         // finishes.
         if (!buildDataAlreadyPresent) {
             build.addAction(buildData);
         }
 
         environment.put(GIT_COMMIT, revToBuild.revision.getSha1String());
         Branch localBranch = Iterables.getFirst(revToBuild.revision.getBranches(),null);
         String localBranchName = getParamLocalBranch(build, listener);
         if (localBranch != null && localBranch.getName() != null) { // null for a detached HEAD
             String remoteBranchName = getBranchName(localBranch);
             environment.put(GIT_BRANCH, remoteBranchName);
 
             LocalBranch lb = getExtensions().get(LocalBranch.class);
             if (lb != null) {
                 String lbn = lb.getLocalBranch();
                 if (lbn == null || lbn.equals("**")) {
                   // local branch is configured with empty value or "**" so use remote branch name for checkout
                   localBranchName = deriveLocalBranchName(remoteBranchName);
                }
                environment.put(GIT_LOCAL_BRANCH, localBranchName);
             }
         }
 
         listener.getLogger().println("Checking out " + revToBuild.revision);
 
         CheckoutCommand checkoutCommand = git.checkout().branch(localBranchName).ref(revToBuild.revision.getSha1String()).deleteBranchIfExist(true);
         for (GitSCMExtension ext : this.getExtensions()) {
             ext.decorateCheckoutCommand(this, build, git, listener, checkoutCommand);
         }
 
         try {
           checkoutCommand.execute();
         } catch (GitLockFailedException e) {
             // Rethrow IOException so the retry will be able to catch it
             throw new IOException("Could not checkout " + revToBuild.revision.getSha1String(), e);
         }
 
         // Needs to be after the checkout so that revToBuild is in the workspace
         try {
             printCommitMessageToLog(listener, git, revToBuild);
         } catch (IOException | ArithmeticException | GitException ge) {
             // JENKINS-45729 reports a git exception when revToBuild cannot be found in the workspace.
             // JENKINS-46628 reports a git exception when revToBuild cannot be found in the workspace.
             // JENKINS-62710 reports a JGit arithmetic exception on an older Java 8 system.
@@ -1411,7 +1422,7 @@
         }
         try {
             // Check for local remotes with no protocol like /path/to/repo.git/
             return !Files.exists(Paths.get(remoteUrl));
         } catch (InvalidPathException e) {
             return true;
         }
@@ -1734,7 +1745,7 @@
          */
         @Deprecated
         public String getGitExe() {
             return gitExe;
         }
 
         /**