Add JSON deserializer

firebase-firestore/src/main/java/com/google/firebase/firestore/local/BundleCache.java

@@ -23,10 +23,10 @@ public interface BundleCache {
    * under the given id.
    */
   @Nullable
-  Bundle getBundleMetadata(String bundleId);
+  BundleMetadata getBundleMetadata(String bundleId);
 
   /** Saves the metadata from a bundle into local storage, using its id as the persistent key. */
-  void saveBundleMetadata(Bundle metadata);
+  void saveBundleMetadata(BundleMetadata metadata);
 
   /**
    * Gets a saved NamedQuery for the given query name. Returns {@code null} if no queries are found

firebase-firestore/src/main/java/com/google/firebase/firestore/local/BundleMetadata.java

@@ -0,0 +1,71 @@
+// Copyright 2021 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.google.firebase.firestore.local;
+
+import com.google.firebase.firestore.model.SnapshotVersion;
+
+/** Represents a Firestore bundle saved by the SDK in its local storage. */
+/* package */ class BundleMetadata {
+  private final String bundleId;
+  private final int version;
+  private final SnapshotVersion createTime;
+
+  public BundleMetadata(String bundleId, int version, SnapshotVersion createTime) {
+    this.bundleId = bundleId;
+    this.version = version;
+    this.createTime = createTime;
+  }
+
+  /**
+   * Returns the ID of the bundle. It is used together with `createTime` to determine if a bundle
+   * has been loaded by the SDK.
+   */
+  public String getBundleId() {
+    return bundleId;
+  }
+
+  /** Returns the schema version of the bundle. */
+  public int getVersion() {
+    return version;
+  }
+
+  /**
+   * Returns the snapshot version of the bundle if created by the Server SDKs, or else
+   * SnapshotVersion.MIN.
+   */
+  public SnapshotVersion getCreateTime() {
+    return createTime;
+  }
+
+  @Override
+  public boolean equals(Object o) {
+    if (this == o) return true;
+    if (o == null || getClass() != o.getClass()) return false;
+
+    BundleMetadata that = (BundleMetadata) o;
+
+    if (version != that.version) return false;
+    if (!bundleId.equals(that.bundleId)) return false;
+    return createTime.equals(that.createTime);
+  }
+
+  @Override
+  public int hashCode() {
+    int result = bundleId.hashCode();
+    result = 31 * result + version;
+    result = 31 * result + createTime.hashCode();
+    return result;
+  }
+}