Define an exception that is thrown if a request is cancelled
Signed-off-by: Edwin Kempin <ekempin@google.com>
Change-Id: Ibd7d788de1f90911ecada25ea45f04c459323e0b
diff --git a/java/com/google/gerrit/server/cancellation/RequestCancelledException.java b/java/com/google/gerrit/server/cancellation/RequestCancelledException.java
new file mode 100644
index 0000000..d1de797
--- /dev/null
+++ b/java/com/google/gerrit/server/cancellation/RequestCancelledException.java
@@ -0,0 +1,62 @@
+// Copyright (C) 2021 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.server.cancellation;
+
+import com.google.gerrit.common.Nullable;
+import java.util.Optional;
+
+/** Exception to signal that the current request is cancelled and should be aborted. */
+public class RequestCancelledException extends RuntimeException {
+ private static final long serialVersionUID = 1L;
+
+ private final RequestStateProvider.Reason cancellationReason;
+ private final Optional<String> cancellationMessage;
+
+ /**
+ * Create a {@code RequestCancelledException}.
+ *
+ * @param cancellationReason the reason why the request is cancelled
+ * @param cancellationMessage an optional message providing details about the cancellation
+ */
+ public RequestCancelledException(
+ RequestStateProvider.Reason cancellationReason, @Nullable String cancellationMessage) {
+ super(createMessage(cancellationReason, cancellationMessage));
+ this.cancellationReason = cancellationReason;
+ this.cancellationMessage = Optional.ofNullable(cancellationMessage);
+ }
+
+ private static String createMessage(
+ RequestStateProvider.Reason cancellationReason, @Nullable String message) {
+ StringBuilder messageBuilder = new StringBuilder();
+ messageBuilder.append(String.format("Request cancelled: %s", cancellationReason.name()));
+ if (message != null) {
+ messageBuilder.append(String.format(" (%s)", message));
+ }
+ return messageBuilder.toString();
+ }
+
+ /** Returns the reason why the request is cancelled. */
+ public RequestStateProvider.Reason getCancellationReason() {
+ return cancellationReason;
+ }
+
+ /**
+ * Returns a message providing details about the cancellation, or {@link Optional#empty()} if none
+ * is available.
+ */
+ public Optional<String> getCancellationMessage() {
+ return cancellationMessage;
+ }
+}
