feat(storage): add delete object contexts sample

java-storage/samples/snippets/src/main/java/com/example/storage/object/DeleteObjectContexts.java

@@ -0,0 +1,71 @@
+/*
+ * Copyright 2026 Google LLC
+ *
+ * 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.example.storage.object;
+
+// [START storage_delete_object_contexts]
+
+import com.google.cloud.storage.Blob;
+import com.google.cloud.storage.BlobId;
+import com.google.cloud.storage.BlobInfo;
+import com.google.cloud.storage.BlobInfo.ObjectContexts;
+import com.google.cloud.storage.BlobInfo.ObjectCustomContextPayload;
+import com.google.cloud.storage.Storage;
+import com.google.cloud.storage.StorageOptions;
+import com.google.common.collect.Maps;
+import java.util.Map;
+
+public class DeleteObjectContexts {
+  public static void deleteObjectContexts(String projectId, String bucketName, String objectName)
+      throws Exception {
+    // The ID of your GCP project
+    // String projectId = "your-project-id";
+
+    // The ID of your GCS bucket
+    // String bucketName = "your-unique-bucket-name";
+
+    // The ID of your GCS object
+    // String objectName = "your-object-name";
+
+    try (Storage storage =
+        StorageOptions.newBuilder().setProjectId(projectId).build().getService()) {
+      BlobId blobId = BlobId.of(bucketName, objectName);
+      Blob blob = storage.get(blobId);
+      if (blob == null) {
+        System.out.println("The object " + objectName + " was not found in " + bucketName);
+        return;
+      }
+
+      // Recommended: Set a generation-match precondition to avoid potential race
+      // conditions and data corruptions. The request to update returns a 412 error if
+      // the object's generation number does not match your precondition.
+      Storage.BlobTargetOption precondition = Storage.BlobTargetOption.generationMatch();
+
+      // To delete all existing custom contexts, set the custom contexts to an empty map.
+      // The update is computed against the contexts of the fetched object, so every
+      // existing key is removed.
+      Map<String, ObjectCustomContextPayload> custom = Maps.newHashMap();
+      ObjectContexts contexts = ObjectContexts.newBuilder().setCustom(custom).build();
+
+      BlobInfo pendingUpdate = blob.toBuilder().setContexts(contexts).build();
+      storage.update(pendingUpdate, precondition);
+
+      System.out.println(
+          "Deleted all custom contexts for object " + objectName + " in bucket " + bucketName);
+    }
+  }
+}
+// [END storage_delete_object_contexts]

java-storage/samples/snippets/src/test/java/com/example/storage/ITObjectSnippets.java

@@ -35,6 +35,7 @@
 import com.example.storage.object.CopyObject;
 import com.example.storage.object.CopyOldVersionOfObject;
 import com.example.storage.object.DeleteObject;
+import com.example.storage.object.DeleteObjectContexts;
 import com.example.storage.object.DeleteOldVersionOfObject;
 import com.example.storage.object.DownloadEncryptedObject;
 import com.example.storage.object.DownloadObject;
@@ -685,6 +686,28 @@ public void testSetObjectContexts() throws Exception {
     assertThat(updatedBlob.getContexts().getCustom().get(key).getValue()).isEqualTo(value);
   }
 
+  @Test
+  public void testDeleteObjectContexts() throws Exception {
+    String blobName = generator.randomObjectName();
+    String key = "test-key-delete";
+    String value = "test-value-delete";
+
+    storage.create(info(blobName), CONTENT, BlobTargetOption.doesNotExist());
+
+    SetObjectContexts.setObjectContexts(
+        GOOGLE_CLOUD_PROJECT, bucket.getName(), blobName, key, value);
+    Blob blobWithContexts = storage.get(bucket.getName(), blobName);
+    assertThat(blobWithContexts.getContexts().getCustom()).containsKey(key);
+
+    DeleteObjectContexts.deleteObjectContexts(GOOGLE_CLOUD_PROJECT, bucket.getName(), blobName);
+    String deleteOutput = stdOut.getCapturedOutputAsUtf8String();
+    assertThat(deleteOutput).contains("Deleted all custom contexts for object " + blobName);
+
+    Blob updatedBlob = storage.get(bucket.getName(), blobName);
+    ObjectContexts contexts = updatedBlob.getContexts();
+    assertTrue(contexts == null || contexts.getCustom().isEmpty());
+  }
+
   @Test
   public void testGetObjectContexts() throws Exception {
     String blobName = generator.randomObjectName();