Move LRP token and tools into domain package

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=129134685

java/google/registry/model/domain/LrpToken.java

@@ -0,0 +1,96 @@
+// Copyright 2016 The Domain Registry 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.model.domain;
+
+import static google.registry.util.PreconditionsUtils.checkArgumentNotNull;
+
+import com.googlecode.objectify.Key;
+import com.googlecode.objectify.annotation.Entity;
+import com.googlecode.objectify.annotation.Id;
+import com.googlecode.objectify.annotation.Index;
+import google.registry.model.BackupGroupRoot;
+import google.registry.model.Buildable;
+import google.registry.model.reporting.HistoryEntry;
+import google.registry.model.reporting.HistoryEntry.Type;
+
+/**
+ * An entity representing a token distributed to eligible LRP registrants.
+ */
+@Entity
+public class LrpToken extends BackupGroupRoot implements Buildable {
+
+  /**
+   * The token's assignee (a unique identifier).
+   */
+  @Id
+  String assignee;
+
+  /**
+   * The secret token assigned to a registrant for the purposes of LRP registration.
+   */
+  @Index
+  String token;
+
+  /**
+   * The key of the history entry for which the token was used. Given LRP is a domain application
+   * phase, this should always be a {@link Type#DOMAIN_APPLICATION_CREATE}.
+   */
+  Key<HistoryEntry> redemptionHistoryEntry;
+  
+  public String getToken() {
+    return token;
+  }
+
+  public String getAssignee() {
+    return assignee;
+  }
+
+  public Key<HistoryEntry> getRedemptionHistoryEntry() {
+    return redemptionHistoryEntry;
+  }
+
+  public boolean isRedeemed() {
+    return redemptionHistoryEntry != null;
+  }
+
+  @Override
+  public Builder asBuilder() {
+    return new Builder(clone(this));
+  }
+
+  /** A builder for constructing {@link LrpToken} objects, since they are immutable. */
+  public static class Builder extends Buildable.Builder<LrpToken> {
+    public Builder() {}
+
+    private Builder(LrpToken instance) {
+      super(instance);
+    }
+    
+    public Builder setAssignee(String assignee) {
+      getInstance().assignee = assignee;
+      return this;
+    }
+
+    public Builder setToken(String token) {
+      getInstance().token = checkArgumentNotNull(token);
+      return this;
+    }
+    
+    public Builder setRedemptionHistoryEntry(Key<HistoryEntry> redemptionHistoryEntry) {
+      getInstance().redemptionHistoryEntry = checkArgumentNotNull(redemptionHistoryEntry);
+      return this;
+    }
+  }
+}