Split ListResult into interface and implementation. Add BlobListResul…

…t for paginated list of Blobs. Add tests.

gcloud-java-storage/src/main/java/com/google/gcloud/storage/BaseListResult.java

@@ -0,0 +1,77 @@
+/*
+ * Copyright 2015 Google Inc. All Rights Reserved.
+ *
+ * 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.gcloud.storage;
+
+import java.io.Serializable;
+import java.util.Collections;
+import java.util.Iterator;
+import java.util.Objects;
+
+/**
+ * Base implementation for Google Cloud storage list result.
+ */
+public class BaseListResult<T extends Serializable> implements ListResult<T>, Serializable {
+
+  private static final long serialVersionUID = -6937287874908527950L;
+
+  private final String cursor;
+  private final Iterable<T> results;
+  private final NextPageFetcher<T> pageFetcher;
+
+  public interface NextPageFetcher<T extends Serializable> extends Serializable {
+    ListResult<T> nextPage();
+  }
+
+  public BaseListResult(NextPageFetcher<T> pageFetcher, String cursor, Iterable<T> results) {
+    this.pageFetcher = pageFetcher;
+    this.cursor = cursor;
+    this.results = results;
+  }
+
+  @Override
+  public String nextPageCursor() {
+    return cursor;
+  }
+
+  @Override
+  public ListResult<T> nextPage() {
+    if (cursor == null || pageFetcher == null) {
+      return null;
+    }
+    return pageFetcher.nextPage();
+  }
+
+  @Override
+  public Iterator<T> iterator() {
+    return results == null ? Collections.<T>emptyIterator() : results.iterator();
+  }
+
+  @Override
+  public int hashCode() {
+    return Objects.hash(cursor, results);
+  }
+
+  @Override
+  public boolean equals(Object obj) {
+    if (!(obj instanceof BaseListResult)) {
+      return false;
+    }
+    BaseListResult<?> other = (BaseListResult<?>) obj;
+    return Objects.equals(cursor, other.cursor)
+        && Objects.equals(results, other.results);
+  }
+}

gcloud-java-storage/src/main/java/com/google/gcloud/storage/BlobListResult.java

@@ -0,0 +1,77 @@
+/*
+ * Copyright 2015 Google Inc. All Rights Reserved.
+ *
+ * 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.gcloud.storage;
+
+import java.util.Iterator;
+import java.util.LinkedList;
+import java.util.List;
+import java.util.Objects;
+
+/**
+ * Implementation of a paginated list of Google Cloud storage {@code Blob}.
+ */
+public class BlobListResult implements ListResult<Blob> {
+
+  private final ListResult<BlobInfo> infoList;
+  private final transient Storage storage;
+  private transient List<Blob> results;
+
+  public BlobListResult(Storage storage, ListResult<BlobInfo> infoList) {
+    this.storage = storage;
+    this.infoList = infoList;
+    this.results = null;
+  }
+
+  @Override
+  public String nextPageCursor() {
+    return infoList.nextPageCursor();
+  }
+
+  @Override
+  public ListResult<Blob> nextPage() {
+    ListResult<BlobInfo> nextPageInfoList = infoList.nextPage();
+    if (nextPageInfoList == null) {
+      return null;
+    }
+    return new BlobListResult(storage, nextPageInfoList);
+  }
+
+  @Override
+  public Iterator<Blob> iterator() {
+    if (results == null) {
+      this.results = new LinkedList<>();
+      for (Iterator<BlobInfo> it = infoList.iterator(); it.hasNext();) {
+        results.add(new Blob(storage, it.next()));
+      }
+    }
+    return results.iterator();
+  }
+
+  @Override
+  public int hashCode() {
+    return Objects.hash(infoList);
+  }
+
+  @Override
+  public boolean equals(Object obj) {
+    if (!(obj instanceof BlobListResult)) {
+      return false;
+    }
+    BlobListResult other = (BlobListResult) obj;
+    return Objects.equals(infoList, other.infoList);
+  }
+}

gcloud-java-storage/src/main/java/com/google/gcloud/storage/ListResult.java

@@ -16,67 +16,28 @@
 
 package com.google.gcloud.storage;
 
-
-import java.io.Serializable;
-import java.util.Collections;
 import java.util.Iterator;
-import java.util.Objects;
 
 /**
- * Google Cloud storage list result.
+ * Interface for Google Cloud storage list result.
  */
-public final class ListResult<T extends Serializable> implements Iterable<T>, Serializable {
-
-  private static final long serialVersionUID = -6937287874908527950L;
-
-  private final String cursor;
-  private final Iterable<T> results;
-  private final NextPageFetcher<T> pageFetcher;
-
-  public interface NextPageFetcher<T extends Serializable> extends Serializable {
-    ListResult<T> nextPage();
-  }
-
-  public ListResult(NextPageFetcher<T> pageFetcher, String cursor, Iterable<T> results) {
-    this.pageFetcher = pageFetcher;
-    this.cursor = cursor;
-    this.results = results;
-  }
+public interface ListResult<T> extends Iterable<T> {
 
   /**
    * Returns the cursor for the nextPage or {@code null} if no more results.
+   * 
+   * @return the string cursor for next page
    */
-  public String nextPageCursor() {
-    return cursor;
-  }
+  public String nextPageCursor();
 
   /**
    * Returns the results of the nextPage or {@code null} if no more result.
+   * 
+   * @return the {@code ListResult} object for the next page
    */
-  public ListResult<T> nextPage() {
-    if (cursor == null || pageFetcher == null) {
-      return null;
-    }
-    return pageFetcher.nextPage();
-  }
-
-  @Override
-  public Iterator<T> iterator() {
-    return results == null ? Collections.<T>emptyIterator() : results.iterator();
-  }
+  public ListResult<T> nextPage();
 
   @Override
-  public int hashCode() {
-    return Objects.hash(cursor, results);
-  }
+  public Iterator<T> iterator();
 
-  @Override
-  public boolean equals(Object obj) {
-    if (!(obj instanceof ListResult)) {
-      return false;
-    }
-    ListResult<?> other = (ListResult<?>) obj;
-    return Objects.equals(cursor, other.cursor)
-        && Objects.equals(results, other.results);
-  }
 }

gcloud-java-storage/src/main/java/com/google/gcloud/storage/StorageImpl.java

@@ -165,7 +165,7 @@ public StorageObject call() {
   }
 
   private static abstract class BasePageFetcher<T extends Serializable>
-      implements ListResult.NextPageFetcher<T> {
+      implements BaseListResult.NextPageFetcher<T> {
 
     private static final long serialVersionUID = 8236329004030295223L;
     protected final Map<StorageRpc.Option, ?> requestOptions;
@@ -234,7 +234,7 @@ public Tuple<String, Iterable<com.google.api.services.storage.model.Bucket>> cal
           }
         }, serviceOptions.retryParams(), EXCEPTION_HANDLER);
     String cursor = result.x();
-    return new ListResult<>(new BucketPageFetcher(serviceOptions, cursor, optionsMap), cursor,
+    return new BaseListResult<>(new BucketPageFetcher(serviceOptions, cursor, optionsMap), cursor,
         Iterables.transform(result.y(),
             new Function<com.google.api.services.storage.model.Bucket, BucketInfo>() {
               @Override
@@ -259,7 +259,7 @@ public Tuple<String, Iterable<StorageObject>> call() {
           }
         }, serviceOptions.retryParams(), EXCEPTION_HANDLER);
     String cursor = result.x();
-    return new ListResult<>(new BlobPageFetcher(bucket, serviceOptions, cursor, optionsMap), cursor,
+    return new BaseListResult<>(new BlobPageFetcher(bucket, serviceOptions, cursor, optionsMap), cursor,
         Iterables.transform(result.y(),
             new Function<StorageObject, BlobInfo>() {
               @Override

gcloud-java-storage/src/test/java/com/google/gcloud/storage/ListResultTest.java → gcloud-java-storage/src/test/java/com/google/gcloud/storage/BaseListResultTest.java

@@ -24,21 +24,21 @@
 
 import java.util.Collections;
 
-public class ListResultTest {
+public class BaseListResultTest {
 
   @Test
   public void testListResult() throws Exception {
     ImmutableList<String> values = ImmutableList.of("1", "2");
-    final ListResult<String> nextResult =
-        new ListResult<>(null, "c", Collections.<String>emptyList());
-    ListResult.NextPageFetcher<String> fetcher = new ListResult.NextPageFetcher<String>() {
+    final BaseListResult<String> nextResult =
+        new BaseListResult<>(null, "c", Collections.<String>emptyList());
+    BaseListResult.NextPageFetcher<String> fetcher = new BaseListResult.NextPageFetcher<String>() {
 
       @Override
-      public ListResult<String> nextPage() {
+      public BaseListResult<String> nextPage() {
         return nextResult;
       }
     };
-    ListResult<String> result = new ListResult<>(fetcher, "c", values);
+    BaseListResult<String> result = new BaseListResult<>(fetcher, "c", values);
     assertEquals(nextResult, result.nextPage());
     assertEquals("c", result.nextPageCursor());
     assertEquals(values, ImmutableList.copyOf(result.iterator()));

gcloud-java-storage/src/test/java/com/google/gcloud/storage/BlobListResultTest.java

@@ -0,0 +1,94 @@
+/*
+ * Copyright 2015 Google Inc. All Rights Reserved.
+ *
+ * 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.gcloud.storage;
+
+import static org.easymock.EasyMock.createStrictMock;
+import static org.easymock.EasyMock.expect;
+import static org.easymock.EasyMock.replay;
+import static org.easymock.EasyMock.verify;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+
+import com.google.common.collect.ImmutableList;
+import java.util.Iterator;
+
+import org.junit.Before;
+import org.junit.Test;
+
+public class BlobListResultTest {
+
+  private static final Iterable<BlobInfo> FIRST_PAGE_RESULTS = ImmutableList.of(
+      BlobInfo.of("b1", "n1"),
+      BlobInfo.of("b2", "n2"));
+
+  private static final Iterable<BlobInfo> SECOND_PAGE_RESULTS = ImmutableList.of(
+      BlobInfo.of("b1", "n1"),
+      BlobInfo.of("b2", "n2"));
+
+  private BaseListResult<BlobInfo> firstPage;
+  private BaseListResult<BlobInfo> secondPage;
+  private Storage storage;
+  private BlobListResult blobListResult;
+
+  @Before
+  public void setUp() throws Exception {
+    firstPage = createStrictMock(BaseListResult.class);
+    secondPage = createStrictMock(BaseListResult.class);
+    storage = createStrictMock(Storage.class);
+    blobListResult = new BlobListResult(storage, firstPage);
+  }
+
+  @Test
+  public void testListResult() throws Exception {
+    expect(firstPage.iterator()).andReturn(FIRST_PAGE_RESULTS.iterator());
+    replay(firstPage);
+    Iterator<BlobInfo> firstPageIterator = FIRST_PAGE_RESULTS.iterator();
+    Iterator<Blob> blobListIterator = blobListResult.iterator();
+    while (blobListIterator.hasNext() && firstPageIterator.hasNext()) {
+      assertEquals(firstPageIterator.next(), blobListIterator.next().info());
+    }
+    assertFalse(blobListIterator.hasNext());
+    assertFalse(firstPageIterator.hasNext());
+    verify(firstPage);
+  }
+
+  @Test
+  public void testCursor() throws Exception {
+    expect(firstPage.nextPageCursor()).andReturn("c");
+    replay(firstPage);
+    assertEquals("c", blobListResult.nextPageCursor());
+    verify(firstPage);
+  }
+
+  @Test
+  public void testNextPage() throws Exception {
+    expect(firstPage.nextPage()).andReturn(secondPage);
+    expect(secondPage.iterator()).andReturn(SECOND_PAGE_RESULTS.iterator());
+    replay(firstPage);
+    replay(secondPage);
+    ListResult<Blob> nextPageResult = blobListResult.nextPage();
+    Iterator<BlobInfo> secondPageIterator = SECOND_PAGE_RESULTS.iterator();
+    Iterator<Blob> blobListIterator = nextPageResult.iterator();
+    while (blobListIterator.hasNext() && secondPageIterator.hasNext()) {
+      assertEquals(secondPageIterator.next(), blobListIterator.next().info());
+    }
+    assertFalse(blobListIterator.hasNext());
+    assertFalse(secondPageIterator.hasNext());
+    verify(firstPage);
+    verify(secondPage);
+  }
+}

gcloud-java-storage/src/test/java/com/google/gcloud/storage/SerializationTest.java

@@ -50,8 +50,8 @@ public class SerializationTest {
       Collections.singletonList(BatchResponse.Result.of(true)),
       Collections.<BatchResponse.Result<BlobInfo>>emptyList(),
       Collections.<BatchResponse.Result<BlobInfo>>emptyList());
-  private static final ListResult<BlobInfo> LIST_RESULT =
-      new ListResult<>(null, "c", Collections.singletonList(BlobInfo.of("b", "n")));
+  private static final BaseListResult<BlobInfo> LIST_RESULT =
+      new BaseListResult<>(null, "c", Collections.singletonList(BlobInfo.of("b", "n")));
   private static final Storage.BlobListOption BLOB_LIST_OPTIONS =
       Storage.BlobListOption.maxResults(100);
   private static final Storage.BlobSourceOption BLOB_SOURCE_OPTIONS =