SDKs send queue is no longer shutdown immediately on re-init

sentry-samples/sentry-samples-console-opentelemetry-noagent/src/test/kotlin/sentry/systemtest/ConsoleApplicationSystemTest.kt

@@ -31,7 +31,7 @@ class ConsoleApplicationSystemTest {
           "OTEL_METRICS_EXPORTER" to "none",
           "OTEL_LOGS_EXPORTER" to "none",
           "OTEL_TRACES_EXPORTER" to "none",
-        )
+        ),
       )
 
     process.waitFor(30, TimeUnit.SECONDS)

sentry/src/main/java/io/sentry/ShutdownHookIntegration.java

@@ -32,7 +32,8 @@ public void register(final @NotNull IScopes scopes, final @NotNull SentryOptions
     Objects.requireNonNull(options, "SentryOptions is required");
 
     if (options.isEnableShutdownHook()) {
-      thread = new Thread(() -> scopes.flush(options.getFlushTimeoutMillis()));
+      thread =
+          new Thread(() -> scopes.flush(options.getFlushTimeoutMillis()), "sentry-shutdownhook");
       handleShutdownInProgress(
           () -> {
             runtime.addShutdownHook(thread);

sentry/src/main/java/io/sentry/transport/AsyncHttpTransport.java

@@ -174,20 +174,23 @@ public void close(final boolean isRestarting) throws IOException {
     executor.shutdown();
     options.getLogger().log(SentryLevel.DEBUG, "Shutting down");
     try {
-      // We need a small timeout to be able to save to disk any rejected envelope
-      long timeout = isRestarting ? 0 : options.getFlushTimeoutMillis();
-      if (!executor.awaitTermination(timeout, TimeUnit.MILLISECONDS)) {
-        options
-            .getLogger()
-            .log(
-                SentryLevel.WARNING,
-                "Failed to shutdown the async connection async sender  within "
-                    + timeout
-                    + " ms. Trying to force it now.");
-        executor.shutdownNow();
-        if (currentRunnable != null) {
-          // We store to disk any envelope that is currently being sent
-          executor.getRejectedExecutionHandler().rejectedExecution(currentRunnable, executor);
+      // only stop sending events on a real shutdown, not on a restart
+      if (!isRestarting) {
+        // We need a small timeout to be able to save to disk any rejected envelope
+        long timeout = options.getFlushTimeoutMillis();
+        if (!executor.awaitTermination(timeout, TimeUnit.MILLISECONDS)) {
+          options
+              .getLogger()
+              .log(
+                  SentryLevel.WARNING,
+                  "Failed to shutdown the async connection async sender  within "
+                      + timeout
+                      + " ms. Trying to force it now.");
+          executor.shutdownNow();
+          if (currentRunnable != null) {
+            // We store to disk any envelope that is currently being sent
+            executor.getRejectedExecutionHandler().rejectedExecution(currentRunnable, executor);
+          }
         }
       }
     } catch (InterruptedException e) {