Adds serialization test. Fixes googleapis#631.

Author: mderka

gcloud-java-dns/src/main/java/com/google/gcloud/dns/DnsOptions.java

@@ -95,4 +95,14 @@ public Builder toBuilder() {
   public static Builder builder() {
     return new Builder();
   }
+
+  @Override
+  public boolean equals(Object obj) {
+    return obj instanceof DnsOptions && baseEquals((DnsOptions) obj);
+  }
+
+  @Override
+  public int hashCode() {
+    return baseHashCode();
+  }
 }

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

@@ -0,0 +1,100 @@
+/*
+ * Copyright 2016 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.dns;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotSame;
+
+import com.google.common.collect.ImmutableList;
+import com.google.gcloud.RetryParams;
+
+import org.junit.Test;
+
+import java.io.ByteArrayInputStream;
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.io.ObjectInputStream;
+import java.io.ObjectOutputStream;
+import java.io.Serializable;
+import java.math.BigInteger;
+
+public class SerializationTest {
+
+  private static final ZoneInfo FULL_ZONE_INFO = Zone.builder("some zone name")
+      .creationTimeMillis(132L)
+      .description("some descriptions")
+      .dnsName("www.example.com")
+      .id("123333")
+      .nameServers(ImmutableList.of("server 1", "server 2"))
+      .nameServerSet("specificationstring")
+      .build();
+  private static final ZoneInfo PARTIAL_ZONE_INFO = Zone.builder("some zone name")
+      .build();
+  private static final ProjectInfo PARTIAL_PROJECT_INFO = ProjectInfo.builder().id("13").build();
+  private static final ProjectInfo FULL_PROJECT_INFO = ProjectInfo.builder()
+      .id("342")
+      .number(new BigInteger("2343245"))
+      .quota(new ProjectInfo.Quota(12, 13, 14, 15, 16, 17))
+      .build();
+  private static final Dns.ZoneListOption ZONE_LIST_OPTION =
+      Dns.ZoneListOption.dnsName("www.example.com.");
+  private static final Dns.DnsRecordListOption DNS_REOCRD_LIST_OPTION =
+      Dns.DnsRecordListOption.fields(Dns.DnsRecordField.TTL);
+  private static final Dns.ChangeRequestListOption CHANGE_REQUEST_LIST_OPTION =
+      Dns.ChangeRequestListOption.fields(Dns.ChangeRequestField.STATUS);
+  private static final Dns.ZoneOption ZONE_OPTION =
+      Dns.ZoneOption.fields(Dns.ZoneField.CREATION_TIME);
+  private static final Dns.ChangeRequestOption CHANGE_REQUEST_OPTION =
+      Dns.ChangeRequestOption.fields(Dns.ChangeRequestField.STATUS);
+  private static final Dns.ProjectOption PROJECT_OPTION =
+      Dns.ProjectOption.fields(Dns.ProjectField.QUOTA);
+  private static final DnsOptions OPTIONS = DnsOptions.builder()
+      .projectId("some-unnecessary-project-ID")
+      .retryParams(RetryParams.defaultInstance())
+      .build();
+  private static final Dns DNS = OPTIONS.service();
+  private static final Zone FULL_ZONE = new Zone(DNS, new ZoneInfo.BuilderImpl(FULL_ZONE_INFO));
+  private static final Zone PARTIAL_ZONE =
+      new Zone(DNS, new ZoneInfo.BuilderImpl(PARTIAL_ZONE_INFO));
+
+  @Test
+  public void testModelAndRequests() throws Exception {
+    Serializable[] objects = {FULL_ZONE_INFO, PARTIAL_ZONE_INFO, ZONE_LIST_OPTION,
+        DNS_REOCRD_LIST_OPTION, CHANGE_REQUEST_LIST_OPTION, ZONE_OPTION, CHANGE_REQUEST_OPTION,
+        PROJECT_OPTION, PARTIAL_PROJECT_INFO, FULL_PROJECT_INFO, OPTIONS, FULL_ZONE, PARTIAL_ZONE,
+        OPTIONS};
+    for (Serializable obj : objects) {
+      Object copy = serializeAndDeserialize(obj);
+      assertEquals(obj, obj);
+      assertEquals(obj, copy);
+      assertNotSame(obj, copy);
+      assertEquals(copy, copy);
+    }
+  }
+
+  @SuppressWarnings("unchecked")
+  private <T> T serializeAndDeserialize(T obj) throws IOException, ClassNotFoundException {
+    ByteArrayOutputStream bytes = new ByteArrayOutputStream();
+    try (ObjectOutputStream output = new ObjectOutputStream(bytes)) {
+      output.writeObject(obj);
+    }
+    try (ObjectInputStream input =
+             new ObjectInputStream(new ByteArrayInputStream(bytes.toByteArray()))) {
+      return (T) input.readObject();
+    }
+  }
+}