Support multiple versions of the EPP Fee Extension

We want to support multiple versions of the fee extension, to allow new features while maintaining backward compatibility. This CL extends the framework and adds one new version, 0.11 (spec version 7), to the existing version 0.6 (spec version 3). A follow-on CL will add version 0.12 (spec version 8).

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=127849044

java/google/registry/model/domain/fee11/FeeCheckCommandExtensionV11.java

@@ -0,0 +1,148 @@
+// 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.fee11;
+
+import static com.google.common.base.Preconditions.checkState;
+
+import com.google.common.base.Optional;
+import com.google.common.collect.ImmutableList;
+import com.google.common.collect.ImmutableSet;
+import google.registry.model.ImmutableObject;
+import google.registry.model.domain.Period;
+import google.registry.model.domain.fee.FeeCheckCommandExtension;
+import google.registry.model.domain.fee.FeeCheckCommandExtensionItem;
+import google.registry.model.domain.fee.FeeCheckResponseExtensionItem;
+import google.registry.model.domain.fee.FeeCheckResponseExtensionItem.Builder;
+import google.registry.model.domain.fee.FeeExtensionCommandDescriptor;
+import google.registry.model.domain.fee11.FeeCheckCommandExtensionV11.FeeCheckCommandExtensionItemV11;
+import javax.xml.bind.annotation.XmlElement;
+import javax.xml.bind.annotation.XmlRootElement;
+import javax.xml.bind.annotation.XmlType;
+import org.joda.money.CurrencyUnit;
+
+/**
+ * Version 0.11 of the fee extension that may be present on domain check commands. Unlike other
+ * versions, there is only one check item; things are nested one level less. However, the response
+ * will have multiple items, one for each domain in the check command.
+ */
+@XmlRootElement(name = "check")
+@XmlType(propOrder = {"command", "currency", "period", "feeClass"})
+public class FeeCheckCommandExtensionV11 extends ImmutableObject
+    implements FeeCheckCommandExtension<
+        FeeCheckCommandExtensionItemV11,
+        FeeCheckResponseExtensionV11> {
+
+  /** The default validity period (if not specified) is 1 year for all operations. */
+  static final Period DEFAULT_PERIOD = Period.create(1, Period.Unit.YEARS);
+
+  /** The command to check. */
+  FeeExtensionCommandDescriptor command;
+
+  /** Three-letter currency code in which results should be returned. */
+  CurrencyUnit currency;
+  
+  /** The period to check. */
+  Period period;
+
+  /** The class to check. */
+  @XmlElement(name = "class")
+  String feeClass;
+  
+  @Override
+  public boolean isCurrencySupported() {
+    return false;
+  }
+  
+  @Override
+  public CurrencyUnit getCurrency() {
+    throw new UnsupportedOperationException("Currency not supported");
+  }
+
+  @Override
+  public ImmutableSet<FeeCheckCommandExtensionItemV11> getItems() {
+    return ImmutableSet.of(new FeeCheckCommandExtensionItemV11());
+  }
+
+  @Override
+  public FeeCheckResponseExtensionV11 createResponse(
+      ImmutableList<? extends FeeCheckResponseExtensionItem> items) {
+    ImmutableList.Builder<FeeCheckResponseExtensionItemV11> builder = new ImmutableList.Builder<>();
+    for (FeeCheckResponseExtensionItem item : items) {
+      checkState(
+          item instanceof FeeCheckResponseExtensionItemV11,
+          "Fee extension response item is not V11");
+      builder.add((FeeCheckResponseExtensionItemV11) item);
+    }
+    return FeeCheckResponseExtensionV11.create(builder.build());
+  }
+
+  /** Implementation of the item interface, returning values of the single "item". */
+  class FeeCheckCommandExtensionItemV11 implements FeeCheckCommandExtensionItem {
+
+    /** The name of the command being checked. */
+    @Override
+    public CommandName getCommandName() {
+      return command.getCommand();
+    }
+  
+    /** The command name before being parsed into an enum, for use in error strings. */
+    @Override
+    public String getUnparsedCommandName() {
+      return command.getUnparsedCommandName();
+    }
+  
+    /** The phase of the command being checked. */
+    @Override
+    public String getPhase() {
+      return command.getPhase();
+    }
+
+    /** The subphase of the command being checked. */
+    @Override
+    public String getSubphase() {
+      return command.getSubphase();
+    }
+
+    @Override
+    public Period getPeriod() {
+      return Optional.fromNullable(period).or(DEFAULT_PERIOD);
+    }
+    
+    @Override
+    public boolean isDomainNameSupported() {
+      return false;
+    }
+    
+    @Override
+    public String getDomainName() {
+      throw new UnsupportedOperationException("Domain not supported");
+    }
+
+    @Override
+    public boolean isCurrencySupported() {
+      return true;
+    }
+
+    @Override
+    public CurrencyUnit getCurrency() {
+      return currency;
+    }
+
+    @Override
+    public Builder createResponseBuilder() {
+      return new FeeCheckResponseExtensionItemV11.Builder();
+    }
+  }
+}