[JENKINS-43507] Tidy up GitHubSCMNavigator

pom.xml

@@ -91,7 +91,7 @@
         <dependency>
             <groupId>org.jenkins-ci.plugins</groupId>
             <artifactId>branch-api</artifactId>
-            <version>2.0.11-20170615.161903-2</version>
+            <version>2.0.11-20170616.163514-4</version>
             <scope>test</scope>
         </dependency>
         <dependency>

src/main/java/org/jenkinsci/plugins/github_branch_source/GitHubSCMBuilder.java

@@ -49,7 +49,6 @@
 import org.eclipse.jgit.lib.Constants;
 import org.eclipse.jgit.transport.RefSpec;
 import org.jenkinsci.plugins.github.config.GitHubServerConfig;
-import org.kohsuke.github.GitHub;
 
 /**
  * Builds a {@link GitSCM} for {@link GitHubSCMSource}.
@@ -58,17 +57,37 @@
  */
 public class GitHubSCMBuilder extends GitSCMBuilder<GitHubSCMBuilder> {
 
+    /**
+     * Singleton instance of {@link HttpsRepositoryUriResolver}.
+     */
     private static final HttpsRepositoryUriResolver HTTPS = new HttpsRepositoryUriResolver();
+    /**
+     * Singleton instance of {@link SshRepositoryUriResolver}.
+     */
     private static final SshRepositoryUriResolver SSH = new SshRepositoryUriResolver();
     /**
      * The context within which credentials should be resolved.
      */
+    @CheckForNull
     private final SCMSourceOwner context;
+    /**
+     * The API URL
+     */
+    @NonNull
     private final String apiUri;
+    /**
+     * The repository owner.
+     */
     @NonNull
     private final String repoOwner;
+    /**
+     * The repository name.
+     */
     @NonNull
     private final String repository;
+    /**
+     * The definitive HTML user-facing URL of the repository (as provided by the GitHub API) if available.
+     */
     @CheckForNull
     private final URL repositoryUrl;
 
@@ -105,14 +124,20 @@ public GitHubSCMBuilder(@NonNull GitHubSCMSource source,
         }
     }
 
+    /**
+     * Tries to guess the HTTPS URL of the Git repository.
+     *
+     * @param source the source.
+     * @return the (possibly incorrect) best guess at the Git repository URL.
+     */
     private static String guessRemote(GitHubSCMSource source) {
         String apiUri = StringUtils.removeEnd(source.getApiUri(), "/");
         if (StringUtils.isBlank(apiUri) || GitHubServerConfig.GITHUB_URL.equals(apiUri)) {
             apiUri = "https://github.com";
         } else {
             apiUri = StringUtils.removeEnd(apiUri, "/api/v3");
         }
-        return  apiUri + "/" + source.getRepoOwner() + "/" + source.getRepository() + ".git";
+        return apiUri + "/" + source.getRepoOwner() + "/" + source.getRepository() + ".git";
     }
 
     /**
@@ -189,7 +214,6 @@ public static RepositoryUriResolver uriResolver(@CheckForNull Item context, @Non
         }
     }
 
-
     /**
      * Updates the {@link GitSCMBuilder#withRemote(String)} based on the current {@link #head()} and
      * {@link #revision()}.