Make Bucket and Blob immutable

mziccard · mziccard · commit 3cf6af39a092 · 2015-09-24T13:54:17.000+02:00
diff --git a/gcloud-java-storage/src/main/java/com/google/gcloud/storage/Blob.java b/gcloud-java-storage/src/main/java/com/google/gcloud/storage/Blob.java
@@ -34,7 +34,7 @@
 public final class Blob {
 
   private final Storage storage;
-  private BlobInfo info;
+  private final BlobInfo info;
 
   public static class BlobSourceOption extends Option {
 
@@ -137,19 +137,31 @@ public byte[] content(Storage.BlobSourceOption... options) {
     return storage.readAllBytes(info.bucket(), info.name(), options);
   }
 
+  /**
+   * Fetches current blob's latest information.
+   *
+   * @param options blob read options
+   * @return a {@code Blob} object with latest information
+   * @throws StorageException upon failure
+   */
+  public Blob reload(BlobSourceOption... options) {
+    return new Blob(storage, storage.get(info.bucket(), info.name(), convert(info, options)));
+  }
+
   /**
    * Update the blob's information. Bucket or blob's name cannot be changed by this method. If you
    * want to rename the blob or move it to a different bucket use the {@link #copyTo} and
-   * {@link #delete} operations.
+   * {@link #delete} operations. A new {@code Blob} object is returned.
    *
    * @param blobInfo new blob's information. Bucket and blob names must match the current ones
    * @param options update options
+   * @return a {@code Blob} object with updated information
    * @throws StorageException upon failure
    */
-  public void update(BlobInfo blobInfo, BlobTargetOption... options) {
+  public Blob update(BlobInfo blobInfo, BlobTargetOption... options) {
     checkArgument(Objects.equals(blobInfo.bucket(), info.bucket()), "Bucket name must match");
     checkArgument(Objects.equals(blobInfo.name(), info.name()), "Blob name must match");
-    info = storage.update(blobInfo, options);
+    return new Blob(storage, storage.update(blobInfo, options));
   }
 
   /**
diff --git a/gcloud-java-storage/src/main/java/com/google/gcloud/storage/Bucket.java b/gcloud-java-storage/src/main/java/com/google/gcloud/storage/Bucket.java
@@ -18,6 +18,7 @@
 
 import static com.google.common.base.Preconditions.checkArgument;
 import static com.google.common.base.Preconditions.checkNotNull;
+import static com.google.gcloud.storage.Blob.BlobSourceOption.convert;
 
 import com.google.gcloud.storage.Storage.BlobSourceOption;
 import com.google.gcloud.storage.Storage.BlobTargetOption;
@@ -34,7 +35,7 @@
 public final class Bucket {
 
   private final Storage storage;
-  private BucketInfo info;
+  private final BucketInfo info;
 
   /**
    * Construct a {@code Bucket} object for the provided {@code BucketInfo}. The storage service is
@@ -78,15 +79,28 @@ public boolean exists() {
   }
 
   /**
-   * Update the bucket's information. Bucket's name cannot be changed.
+   * Fetches current bucket's latest information.
+   *
+   * @param options bucket read options
+   * @return a {@code Bucket} object with latest information
+   * @throws StorageException upon failure
+   */
+  public Bucket reload(BucketSourceOption... options) {
+    return new Bucket(storage, storage.get(info.name(), options));
+  }
+
+  /**
+   * Update the bucket's information. Bucket's name cannot be changed. A new {@code Bucket} object
+   * is returned.
    *
    * @param bucketInfo new bucket's information. Name must match the one of the current bucket
    * @param options update options
+   * @return a {@code Bucket} object with updated information
    * @throws StorageException upon failure
    */
-  public void update(BucketInfo bucketInfo, BucketTargetOption... options) {
+  public Bucket update(BucketInfo bucketInfo, BucketTargetOption... options) {
     checkArgument(Objects.equals(bucketInfo.name(), info.name()), "Bucket name must match");
-    info = storage.update(bucketInfo, options);
+    return new Bucket(storage, storage.update(bucketInfo, options));
   }
 
   /**
diff --git a/gcloud-java-storage/src/test/java/com/google/gcloud/storage/BlobTest.java b/gcloud-java-storage/src/test/java/com/google/gcloud/storage/BlobTest.java
@@ -81,14 +81,24 @@ public void testContent() throws Exception {
     assertArrayEquals(content, blob.content());
   }
 
+  @Test
+  public void testReload() throws Exception {
+    BlobInfo updatedInfo = BLOB_INFO.toBuilder().cacheControl("c").build();
+    expect(storage.get(BLOB_INFO.bucket(), BLOB_INFO.name())).andReturn(updatedInfo);
+    replay(storage);
+    Blob updatedBlob = blob.reload();
+    assertSame(storage, blob.storage());
+    assertEquals(updatedInfo, updatedBlob.info());
+  }
+
   @Test
   public void testUpdate() throws Exception {
     BlobInfo updatedInfo = BLOB_INFO.toBuilder().cacheControl("c").build();
     expect(storage.update(updatedInfo)).andReturn(updatedInfo);
     replay(storage);
-    blob.update(updatedInfo);
+    Blob updatedBlob = blob.update(updatedInfo);
     assertSame(storage, blob.storage());
-    assertEquals(updatedInfo, blob.info());
+    assertEquals(updatedInfo, updatedBlob.info());
   }
 
   @Test
diff --git a/gcloud-java-storage/src/test/java/com/google/gcloud/storage/BucketTest.java b/gcloud-java-storage/src/test/java/com/google/gcloud/storage/BucketTest.java
@@ -80,14 +80,24 @@ public void testExists_False() throws Exception {
     assertFalse(bucket.exists());
   }
 
+  @Test
+  public void testReload() throws Exception {
+    BucketInfo updatedInfo = BUCKET_INFO.toBuilder().notFoundPage("p").build();
+    expect(storage.get(updatedInfo.name())).andReturn(updatedInfo);
+    replay(storage);
+    Bucket updatedBucket = bucket.reload();
+    assertSame(storage, bucket.storage());
+    assertEquals(updatedInfo, updatedBucket.info());
+  }
+
   @Test
   public void testUpdate() throws Exception {
     BucketInfo updatedInfo = BUCKET_INFO.toBuilder().notFoundPage("p").build();
     expect(storage.update(updatedInfo)).andReturn(updatedInfo);
     replay(storage);
-    bucket.update(updatedInfo);
+    Bucket updatedBucket = bucket.update(updatedInfo);
     assertSame(storage, bucket.storage());
-    assertEquals(updatedInfo, bucket.info());
+    assertEquals(updatedInfo, updatedBucket.info());
   }
 
   @Test
