Add a command-line tool suitable for tech support usage

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=213634869

java/google/registry/tools/UpdateSandboxTldCommand.java

@@ -0,0 +1,32 @@
+// Copyright 2017 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.base.Preconditions.checkArgument;
+
+import com.beust.jcommander.Parameters;
+import google.registry.config.RegistryEnvironment;
+
+/** Command to update a TLD in sandbox, separated out for gTech use. */
+@Parameters(separators = " =", commandDescription = "Update new sandbox TLD(s)")
+final class UpdateSandboxTldCommand extends UpdateTldCommand {
+
+  @Override
+  void assertAllowedEnvironment() {
+    checkArgument(
+        RegistryEnvironment.get() == RegistryEnvironment.SANDBOX,
+        "This command can only be run in the sandbox environment");
+  }
+}