Add a nomulus tool command to get allocation tokens

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=239624232

java/google/registry/tools/GetAllocationTokenCommand.java

@@ -0,0 +1,57 @@
+// Copyright 2019 The Nomulus Authors. 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 google.registry.tools;
+
+import static com.google.common.collect.ImmutableList.toImmutableList;
+import static google.registry.model.ofy.ObjectifyService.ofy;
+
+import com.beust.jcommander.Parameter;
+import com.beust.jcommander.Parameters;
+import com.google.common.collect.ImmutableList;
+import com.google.common.collect.ImmutableMap;
+import com.google.common.collect.Lists;
+import com.googlecode.objectify.Key;
+import google.registry.model.domain.token.AllocationToken;
+import java.util.List;
+
+/** Command to show allocation tokens. */
+@Parameters(separators = " =", commandDescription = "Show allocation token(s)")
+final class GetAllocationTokenCommand implements CommandWithRemoteApi {
+
+  @Parameter(
+      description = "Allocation token(s)",
+      required = true)
+  private List<String> mainParameters;
+
+  private static final int BATCH_SIZE = 20;
+
+  @Override
+  public void run() {
+    ImmutableMap.Builder<String, AllocationToken> builder = new ImmutableMap.Builder<>();
+    for (List<String> tokens : Lists.partition(mainParameters, BATCH_SIZE)) {
+      ImmutableList<Key<AllocationToken>> keys =
+          tokens.stream().map(t -> Key.create(AllocationToken.class, t)).collect(toImmutableList());
+      ofy().load().keys(keys).forEach((k, v) -> builder.put(k.getName(), v));
+    }
+    ImmutableMap<String, AllocationToken> loadedTokens = builder.build();
+
+    for (String token : mainParameters) {
+      System.out.println(
+          loadedTokens.containsKey(token)
+              ? loadedTokens.get(token)
+              : String.format("Token %s does not exist.", token));
+    }
+  }
+}