Rename LrpToken to LrpTokenEntity

This is to better distinguish between an LRP "token" (the string passed along in EPP) and the datastore entity that contains the token and all metadata.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=135943480

java/google/registry/model/domain/LrpTokenEntity.java

@@ -0,0 +1,128 @@
+// Copyright 2016 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.model.domain;
+
+import static google.registry.util.CollectionUtils.nullToEmptyImmutableCopy;
+import static google.registry.util.PreconditionsUtils.checkArgumentNotNull;
+
+import com.googlecode.objectify.Key;
+import com.googlecode.objectify.annotation.EmbedMap;
+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 java.util.Map;
+import java.util.Set;
+
+/** An entity representing a token distributed to eligible LRP registrants. */
+@Entity
+public class LrpTokenEntity extends BackupGroupRoot implements Buildable {
+
+  /**
+   * The secret token assigned to a registrant for the purposes of LRP registration.
+   */
+  @Id
+  String token;
+
+  /**
+   * The token's assignee (additional metadata for identifying the owner of the token, the details
+   * of which might differ from TLD to TLD).
+   */
+  @Index
+  String assignee;
+
+  /**
+   * A list of TLDs for which this LRP token is valid.
+   */
+  Set<String> validTlds;
+
+  /**
+   * The key of the history entry for which the token was used.
+   */
+  Key<HistoryEntry> redemptionHistoryEntry;
+
+  /**
+   * A set of key-value properties associated with the LRP token. This map can be used to store
+   * additional metadata about the assignee or space of domain names for which this token can be
+   * valid.
+   */
+  @EmbedMap
+  Map<String, String> metadata;
+
+  public String getToken() {
+    return token;
+  }
+
+  public String getAssignee() {
+    return assignee;
+  }
+
+  public Key<HistoryEntry> getRedemptionHistoryEntry() {
+    return redemptionHistoryEntry;
+  }
+
+  public boolean isRedeemed() {
+    return redemptionHistoryEntry != null;
+  }
+
+  public Set<String> getValidTlds() {
+    return nullToEmptyImmutableCopy(validTlds);
+  }
+
+  public Map<String, String> getMetadata() {
+    return nullToEmptyImmutableCopy(metadata);
+  }
+
+  @Override
+  public Builder asBuilder() {
+    return new Builder(clone(this));
+  }
+
+  /** A builder for constructing {@link LrpTokenEntity} objects, since they are immutable. */
+  public static class Builder extends Buildable.Builder<LrpTokenEntity> {
+    public Builder() {}
+
+    private Builder(LrpTokenEntity 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;
+    }
+
+    public Builder setValidTlds(Set<String> validTlds) {
+      getInstance().validTlds = validTlds;
+      return this;
+    }
+
+    public Builder setMetadata(Map<String, String> metadata) {
+      getInstance().metadata = metadata;
+      return this;
+    }
+  }
+}