fix(threads): Cap updating threads

Submit each repository update runnable to an executor service with fixed number of threads.

This allows having a maximum cap number of threads for projects with 10s or 20s repos.

Closes #55

Signed-off-by: jchrist <[email protected]>

src/main/java/gr/jchrist/gitextender/GitExtenderUpdateAll.java

@@ -19,6 +19,7 @@
 
 import java.util.List;
 import java.util.concurrent.CountDownLatch;
+import java.util.concurrent.Executors;
 import java.util.concurrent.atomic.AtomicBoolean;
 import java.util.stream.Collectors;
 
@@ -122,13 +123,12 @@ private void updateRepositories(@NotNull Project project, @NotNull List<GitRepos
         GitExtenderSettingsHandler settingsHandler = new GitExtenderSettingsHandler();
         final GitExtenderSettings settings = settingsHandler.loadSettings();
         this.updateCountDown = new CountDownLatch(repositories.size());
+        final var es = Executors.newFixedThreadPool(Math.min(repositories.size(), 3));
         repositories.forEach(repo ->
-                new Thread(new BackgroundableRepoUpdateTask(repo,
-                        VcsImplUtil.getShortVcsRootName(repo.getProject(), repo.getRoot()),
-                        settings, updateCountDown))
-                        .start());
+                es.submit(new BackgroundableRepoUpdateTask(repo, VcsImplUtil.getShortVcsRootName(repo.getProject(), repo.getRoot()),
+                        settings, updateCountDown)));
         UpdateExecutingBackgroundTask ubt = new UpdateExecutingBackgroundTask(project, "GitExtender Update All Repos",
-                accessToken, updateCountDown, executingFlag);
+                accessToken, updateCountDown, es, executingFlag);
         //ubt.queue();
         new Thread(ubt::queue).start();
     }

src/main/java/gr/jchrist/gitextender/UpdateExecutingBackgroundTask.java

@@ -9,21 +9,24 @@
 import org.jetbrains.annotations.NotNull;
 
 import java.util.concurrent.CountDownLatch;
+import java.util.concurrent.ExecutorService;
 import java.util.concurrent.TimeUnit;
 import java.util.concurrent.atomic.AtomicBoolean;
 
 public class UpdateExecutingBackgroundTask extends Task.Backgroundable {
     private static final Logger logger = Logger.getInstance(UpdateExecutingBackgroundTask.class);
     protected AccessToken accessToken;
     protected CountDownLatch updateCountDownLatch;
+    protected ExecutorService executor;
     protected AtomicBoolean executingFlag;
 
     public UpdateExecutingBackgroundTask(
             Project project, String title,
-            AccessToken accessToken, CountDownLatch updatingLatch, AtomicBoolean executing) {
+            AccessToken accessToken, CountDownLatch updatingLatch, ExecutorService executor, AtomicBoolean executing) {
         super(project, title, false, PerformInBackgroundOption.ALWAYS_BACKGROUND);
         this.accessToken = accessToken;
         this.updateCountDownLatch = updatingLatch;
+        this.executor = executor;
         this.executingFlag = executing;
     }
 
@@ -36,6 +39,11 @@ public void run(@NotNull ProgressIndicator indicator) {
         } catch (Exception e) {
             logger.warn("error awaiting update latch!", e);
         }
+        try {
+            executor.shutdownNow();
+        } catch (Exception e) {
+            logger.warn("error shutting down executor", e);
+        }
         logger.debug("update finished - " + Thread.currentThread().getName());
         //the last task finished should clean up, release project changes and show info notification
         accessToken.finish();