fix(task): wrong cancellation implementation. Closes #1035.

HMCL/src/main/java/org/jackhuang/hmcl/ui/download/DownloadPage.java

@@ -57,6 +57,7 @@ import org.jetbrains.annotations.Nullable;
 import java.nio.file.Path;
 import java.util.HashMap;
 import java.util.Map;
+import java.util.concurrent.CancellationException;
 
 import static org.jackhuang.hmcl.ui.FXUtils.runInFX;
 import static org.jackhuang.hmcl.ui.versions.VersionPage.wrap;
@@ -166,9 +167,13 @@ public class DownloadPage extends BorderPane implements DecoratorPage {
             FileDownloadTask task = new FileDownloadTask(NetworkUtils.toURL(file.getFile().getUrl()), dest.toFile());
             task.setName(file.getName());
             return task;
-        }).whenComplete(exception -> {
+        }).whenComplete(Schedulers.javafx(), exception -> {
             if (exception != null) {
+                if (exception instanceof CancellationException) {
+                    Controllers.showToast(i18n("message.cancelled"));
+                } else {
                     Controllers.dialog(DownloadProviders.localizeErrorMessage(exception), i18n("install.failed.downloading"), MessageDialogPane.MessageType.ERROR);
+                }
             } else {
                 Controllers.showToast(i18n("install.success"));
             }

HMCL/src/main/resources/assets/lang/I18N.properties

@@ -420,6 +420,7 @@ logwindow.export_game_crash_logs=Export game crash info
 
 main_page=Home
 
+message.cancelled=Operation was cancelled
 message.confirm=Confirm
 message.copied=Copied to clipboard
 message.doing=Please wait

HMCL/src/main/resources/assets/lang/I18N_zh.properties

@@ -420,6 +420,7 @@ logwindow.export_game_crash_logs=導出遊戲崩潰訊息
 
 main_page=首頁
 
+message.cancelled=操作被取消
 message.confirm=提示
 message.copied=已複製到剪貼板
 message.doing=請耐心等待

HMCL/src/main/resources/assets/lang/I18N_zh_CN.properties

@@ -420,6 +420,7 @@ logwindow.export_game_crash_logs=导出游戏崩溃信息
 
 main_page=主页
 
+message.cancelled=操作被取消
 message.confirm=提示
 message.copied=已复制到剪贴板
 message.doing=请耐心等待

HMCLCore/src/main/java/org/jackhuang/hmcl/task/AsyncTaskExecutor.java

@@ -95,7 +95,6 @@ public final class AsyncTaskExecutor extends TaskExecutor {
         }
 
         cancelled.set(true);
-        future.cancel(true);
     }
 
     private CompletableFuture<?> executeTasksExceptionally(Task<?> parentTask, Collection<Task<?>> tasks) {
@@ -229,13 +228,15 @@ public final class AsyncTaskExecutor extends TaskExecutor {
                 .thenComposeAsync(dependentsException -> {
                     boolean isDependentsSucceeded = dependentsException == null;
 
-                    if (!isDependentsSucceeded && task.isRelyingOnDependents()) {
+                    if (isDependentsSucceeded) {
+                        task.setDependentsSucceeded();
+                    } else {
                         task.setException(dependentsException);
+
+                        if (task.isRelyingOnDependents()) {
                             rethrow(dependentsException);
                         }
-
+                    }
-                    if (isDependentsSucceeded)
-                        task.setDependentsSucceeded();
 
                     return CompletableFuture.runAsync(wrap(() -> {
                         task.setState(Task.TaskState.RUNNING);
@@ -263,11 +264,13 @@ public final class AsyncTaskExecutor extends TaskExecutor {
                 .thenApplyAsync(dependenciesException -> {
                     boolean isDependenciesSucceeded = dependenciesException == null;
 
-                    if (!isDependenciesSucceeded && task.isRelyingOnDependencies()) {
+                    if (!isDependenciesSucceeded) {
                         Logging.LOG.severe("Subtasks failed for " + task.getName());
                         task.setException(dependenciesException);
+                        if (task.isRelyingOnDependencies()) {
                             rethrow(dependenciesException);
                         }
+                    }
 
                     checkCancellation();
 
@@ -285,23 +288,20 @@ public final class AsyncTaskExecutor extends TaskExecutor {
                 .exceptionally(throwable -> {
                     Throwable resolved = resolveException(throwable);
                     if (resolved instanceof Exception) {
-                        Exception e = (Exception) resolved;
+                        Exception e = convertInterruptedException((Exception) resolved);
-                        if (e instanceof InterruptedException || e instanceof CancellationException) {
+                        task.setException(e);
-                            task.setException(null);
+                        exception = e;
+                        if (e instanceof CancellationException) {
                             if (task.getSignificance().shouldLog()) {
                                 Logging.LOG.log(Level.FINE, "Task aborted: " + task.getName());
                             }
-                            task.onDone().fireEvent(new TaskEvent(this, task, true));
-                            taskListeners.forEach(it -> it.onFailed(task, e));
                         } else {
-                            task.setException(e);
-                            exception = e;
                             if (task.getSignificance().shouldLog()) {
                                 Logging.LOG.log(Level.FINE, "Task failed: " + task.getName(), e);
                             }
+                        }
                         task.onDone().fireEvent(new TaskEvent(this, task, true));
                         taskListeners.forEach(it -> it.onFailed(task, e));
-                        }
 
                         task.setState(Task.TaskState.FAILED);
                     }
@@ -331,6 +331,14 @@ public final class AsyncTaskExecutor extends TaskExecutor {
         }
     }
 
+    private static Exception convertInterruptedException(Exception e) {
+        if (e instanceof InterruptedException) {
+            return new CancellationException(e.getMessage());
+        } else {
+            return e;
+        }
+    }
+
     private static Thread.UncaughtExceptionHandler uncaughtExceptionHandler = null;
 
     public static void setUncaughtExceptionHandler(Thread.UncaughtExceptionHandler uncaughtExceptionHandler) {

HMCLCore/src/main/java/org/jackhuang/hmcl/task/Task.java

@@ -665,14 +665,14 @@ public abstract class Task<T> {
             @Override
             public void execute() throws Exception {
                 if (isDependentsSucceeded() != (Task.this.getException() == null))
-                    throw new AssertionError("When dependents succeeded, Task.exception must be nonnull.");
+                    throw new AssertionError("When whenComplete succeeded, Task.exception must be null.");
 
                 action.execute(Task.this.getException());
 
                 if (!isDependentsSucceeded()) {
                     setSignificance(TaskSignificance.MINOR);
                     if (Task.this.getException() == null)
-                        throw new CancellationException();
+                        throw new AssertionError("When failed, exception cannot be null");
                     else
                         throw Task.this.getException();
                 }