fix(consumers): prevent await deadlock on ContextCallable failure

hugegraph-server/hugegraph-core/src/main/java/org/apache/hugegraph/util/Consumers.java

@@ -104,9 +104,23 @@ public void start(String name) {
         LOG.info("Starting {} workers[{}] with queue size {}...",
                  this.workers, name, this.queueSize);
         for (int i = 0; i < this.workers; i++) {
-            this.runningFutures.add(
-                    this.executor.submit(new ContextCallable<>(this::runAndDone)));
+            this.runningFutures.add(this.executor.submit(this::safeRun));
         }
+
+    }
+    private Void safeRun() {
+        try {
+            new ContextCallable<>(this::runAndDone).call();
+        } catch (Throwable e) {
+            LOG.error("Worker failed before runAndDone()", e);
+            if (this.exception == null) {
+                this.exception = e;
+            }
+            exceptionHandle(e);
+        } finally {
+            this.latch.countDown();
+        }
+        return null;
     }
 
     private Void runAndDone() {
@@ -124,7 +138,6 @@ private Void runAndDone() {
             exceptionHandle(e);
         } finally {
             this.done();
-            this.latch.countDown();
         }
         return null;
     }

hugegraph-server/hugegraph-test/src/main/java/org/apache/hugegraph/unit/util/ConsumersTest.java

@@ -0,0 +1,81 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You 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 org.apache.hugegraph.unit.util;
+
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+import java.util.concurrent.atomic.AtomicInteger;
+
+import org.apache.hugegraph.testutil.Assert;
+import org.apache.hugegraph.util.Consumers;
+import org.junit.Test;
+
+public class ConsumersTest {
+
+    @Test(timeout = 5000)
+    public void testStartProvideAwaitNormal() throws Throwable {
+        ExecutorService executor = Executors.newFixedThreadPool(2);
+        try {
+            AtomicInteger processed = new AtomicInteger();
+
+            Consumers<Integer> consumers = new Consumers<>(executor, v -> {
+                processed.incrementAndGet();
+            });
+
+            consumers.start("test");
+            for (int i = 0; i < 50; i++) {
+                consumers.provide(i);
+            }
+            consumers.await();
+
+            Assert.assertEquals("Should process all provided elements",
+                                50, processed.get());
+        } finally {
+            executor.shutdownNow();
+        }
+    }
+
+    @Test(timeout = 5000)
+    public void testAwaitThrowsWhenConsumerThrows() throws Throwable {
+        ExecutorService executor = Executors.newFixedThreadPool(2);
+        try {
+            final String msg = "Injected exception for test";
+
+            Consumers<Integer> consumers = new Consumers<>(executor, v -> {
+                throw new RuntimeException(msg);
+            });
+
+            consumers.start("test");
+            consumers.provide(1);
+
+            try {
+                consumers.await();
+                Assert.fail("Expected await() to throw when consumer throws");
+            } catch (Throwable t) {
+                Throwable root = t.getCause() != null ? t.getCause() : t;
+                Assert.assertTrue("Expected RuntimeException, but got: " + root,
+                                  root instanceof RuntimeException);
+                Assert.assertTrue("Exception message should contain injected message",
+                                  root.getMessage() != null &&
+                                  root.getMessage().contains(msg));
+            }
+        } finally {
+            executor.shutdownNow();
+        }
+    }
+}