Import code from internal repository to git

java/com/google/domain/registry/tools/Command.java

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+// 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.domain.registry.tools;
+
+/** Interface of all commands. */
+public interface Command {
+
+  /** Performs the command. */
+  void run() throws Exception;
+
+  /**
+   * Marker interface for commands that use the remote api.
+   * <p>
+   * Just implementing this is sufficient to use the remote api; {@link RegistryTool} will install
+   * it as needed.
+   */
+  public interface RemoteApiCommand extends Command {}
+
+  /**
+   * Marker interface for commands that are gTech safe.
+   */
+  public interface GtechCommand extends Command {}
+}