Add annotation processor to generate converter for VKey (#566)

core/build.gradle

@@ -295,6 +295,8 @@ dependencies {
   testAnnotationProcessor deps['com.google.auto.value:auto-value']
   annotationProcessor deps['com.google.dagger:dagger-compiler']
   testAnnotationProcessor deps['com.google.dagger:dagger-compiler']
+  annotationProcessor project(':processor')
+  testAnnotationProcessor project(':processor')
 
   testCompile deps['com.google.appengine:appengine-testing']
   testCompile deps['com.google.guava:guava-testlib']

core/gradle/dependency-locks/annotationProcessor.lockfile

@@ -12,24 +12,24 @@ com.google.dagger:dagger-producers:2.21
 com.google.dagger:dagger-spi:2.21
 com.google.dagger:dagger:2.21
 com.google.errorprone:error_prone_annotation:2.3.3
-com.google.errorprone:error_prone_annotations:2.3.3
+com.google.errorprone:error_prone_annotations:2.3.4
 com.google.errorprone:error_prone_check_api:2.3.3
 com.google.errorprone:error_prone_core:2.3.3
 com.google.errorprone:error_prone_type_annotations:2.3.3
 com.google.errorprone:javac-shaded:9-dev-r4023-3
 com.google.googlejavaformat:google-java-format:1.5
 com.google.guava:failureaccess:1.0.1
-com.google.guava:guava:27.0.1-jre
+com.google.guava:guava:28.2-jre
 com.google.guava:listenablefuture:9999.0-empty-to-avoid-conflict-with-guava
-com.google.j2objc:j2objc-annotations:1.1
+com.google.j2objc:j2objc-annotations:1.3
 com.google.protobuf:protobuf-java:3.4.0
 com.googlecode.java-diff-utils:diffutils:1.3.0
-com.squareup:javapoet:1.11.1
+com.squareup:javapoet:1.12.1
 javax.annotation:jsr250-api:1.0
 javax.inject:javax.inject:1
+javax.persistence:javax.persistence-api:2.2
 org.checkerframework:checker-compat-qual:2.5.3
-org.checkerframework:checker-qual:2.5.3
+org.checkerframework:checker-qual:2.10.0
 org.checkerframework:dataflow:2.5.3
 org.checkerframework:javacutil:2.5.3
-org.codehaus.mojo:animal-sniffer-annotations:1.17
 org.pcollections:pcollections:2.1.2

core/gradle/dependency-locks/testAnnotationProcessor.lockfile

@@ -12,24 +12,24 @@ com.google.dagger:dagger-producers:2.21
 com.google.dagger:dagger-spi:2.21
 com.google.dagger:dagger:2.21
 com.google.errorprone:error_prone_annotation:2.3.3
-com.google.errorprone:error_prone_annotations:2.3.3
+com.google.errorprone:error_prone_annotations:2.3.4
 com.google.errorprone:error_prone_check_api:2.3.3
 com.google.errorprone:error_prone_core:2.3.3
 com.google.errorprone:error_prone_type_annotations:2.3.3
 com.google.errorprone:javac-shaded:9-dev-r4023-3
 com.google.googlejavaformat:google-java-format:1.5
 com.google.guava:failureaccess:1.0.1
-com.google.guava:guava:27.0.1-jre
+com.google.guava:guava:28.2-jre
 com.google.guava:listenablefuture:9999.0-empty-to-avoid-conflict-with-guava
-com.google.j2objc:j2objc-annotations:1.1
+com.google.j2objc:j2objc-annotations:1.3
 com.google.protobuf:protobuf-java:3.4.0
 com.googlecode.java-diff-utils:diffutils:1.3.0
-com.squareup:javapoet:1.11.1
+com.squareup:javapoet:1.12.1
 javax.annotation:jsr250-api:1.0
 javax.inject:javax.inject:1
+javax.persistence:javax.persistence-api:2.2
 org.checkerframework:checker-compat-qual:2.5.3
-org.checkerframework:checker-qual:2.5.3
+org.checkerframework:checker-qual:2.10.0
 org.checkerframework:dataflow:2.5.3
 org.checkerframework:javacutil:2.5.3
-org.codehaus.mojo:animal-sniffer-annotations:1.17
 org.pcollections:pcollections:2.1.2

core/src/main/java/google/registry/model/EppResource.java

@@ -135,7 +135,7 @@ public abstract class EppResource extends BackupGroupRoot implements Buildable {
   @Transient
   ImmutableSortedMap<DateTime, Key<CommitLogManifest>> revisions = ImmutableSortedMap.of();
 
-  public final String getRepoId() {
+  public String getRepoId() {
     return repoId;
   }
 

core/src/main/java/google/registry/model/domain/DomainBase.java

@@ -77,7 +77,6 @@ import javax.annotation.Nullable;
 import javax.persistence.AttributeOverride;
 import javax.persistence.AttributeOverrides;
 import javax.persistence.Column;
-import javax.persistence.Convert;
 import javax.persistence.ElementCollection;
 import javax.persistence.Embedded;
 import javax.persistence.JoinTable;
@@ -147,7 +146,6 @@ public class DomainBase extends EppResource
   @Ignore
   @ElementCollection
   @JoinTable(name = "DomainHost")
-  @Convert(converter = HostResource.VKeyHostResourceConverter.class)
   Set<VKey<HostResource>> nsHostVKeys;
 
   /**

core/src/main/java/google/registry/model/host/HostResource.java

@@ -34,7 +34,7 @@ import google.registry.model.annotations.ReportedOn;
 import google.registry.model.domain.DomainBase;
 import google.registry.model.transfer.TransferData;
 import google.registry.persistence.VKey;
-import google.registry.persistence.converter.VKeyConverter;
+import google.registry.persistence.WithStringVKey;
 import java.net.InetAddress;
 import java.util.Optional;
 import java.util.Set;
@@ -54,6 +54,7 @@ import org.joda.time.DateTime;
 @Entity
 @javax.persistence.Entity
 @ExternalMessagingName("host")
+@WithStringVKey
 public class HostResource extends EppResource implements ForeignKeyedEppResource {
 
   /**
@@ -212,11 +213,4 @@ public class HostResource extends EppResource implements ForeignKeyedEppResource
       return this;
     }
   }
-
-  public static class VKeyHostResourceConverter extends VKeyConverter<HostResource> {
-    @Override
-    protected Class<HostResource> getAttributeClass() {
-      return HostResource.class;
-    }
-  }
 }

core/src/main/java/google/registry/persistence/VKey.java

@@ -15,6 +15,7 @@
 package google.registry.persistence;
 
 import static com.google.common.base.Preconditions.checkState;
+import static google.registry.util.PreconditionsUtils.checkArgumentNotNull;
 
 import google.registry.model.ImmutableObject;
 import java.util.Optional;
@@ -41,20 +42,31 @@ public class VKey<T> extends ImmutableObject {
     this.primaryKey = primaryKey;
   }
 
-  public static <T> VKey<T> createSql(Class<? extends T> kind, Object primaryKey) {
+  /** Creates a {@link VKey} which only contains the sql primary key. */
-    return new VKey(kind, null, primaryKey);
+  public static <T> VKey<T> createSql(Class<? extends T> kind, Object sqlKey) {
+    checkArgumentNotNull(kind, "kind must not be null");
+    checkArgumentNotNull(sqlKey, "sqlKey must not be null");
+    return new VKey(kind, null, sqlKey);
   }
 
+  /** Creates a {@link VKey} which only contains the ofy primary key. */
   public static <T> VKey<T> createOfy(
-      Class<? extends T> kind, com.googlecode.objectify.Key<T> ofyKey) {
+      Class<? extends T> kind, com.googlecode.objectify.Key<? extends T> ofyKey) {
+    checkArgumentNotNull(kind, "kind must not be null");
+    checkArgumentNotNull(ofyKey, "ofyKey must not be null");
     return new VKey(kind, ofyKey, null);
   }
 
+  /** Creates a {@link VKey} which only contains both sql and ofy primary key. */
   public static <T> VKey<T> create(
-      Class<? extends T> kind, Object primaryKey, com.googlecode.objectify.Key ofyKey) {
+      Class<? extends T> kind, Object sqlKey, com.googlecode.objectify.Key ofyKey) {
-    return new VKey(kind, ofyKey, primaryKey);
+    checkArgumentNotNull(kind, "kind must not be null");
+    checkArgumentNotNull(sqlKey, "sqlKey must not be null");
+    checkArgumentNotNull(ofyKey, "ofyKey must not be null");
+    return new VKey(kind, ofyKey, sqlKey);
   }
 
+  /** Returns the type of the entity. */
   public Class<? extends T> getKind() {
     return this.kind;
   }

core/src/main/java/google/registry/persistence/WithLongVKey.java

@@ -0,0 +1,34 @@
+// Copyright 2020 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.persistence;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Target;
+import javax.persistence.AttributeConverter;
+import javax.persistence.Entity;
+
+/**
+ * Annotation for {@link Entity} which id is long type and needs an {@link AttributeConverter} for
+ * its VKey.
+ */
+@Target({ElementType.TYPE})
+public @interface WithLongVKey {
+  /**
+   * Sets the suffix of the class name for the {@link AttributeConverter} generated by
+   * LongVKeyProcessor. If not set, the suffix will be the type name of the VKey. Note that the
+   * class name will be "VKeyConverter_" concatenated with the suffix.
+   */
+  String classNameSuffix() default "";
+}

core/src/main/java/google/registry/persistence/WithStringVKey.java

@@ -0,0 +1,34 @@
+// Copyright 2020 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.persistence;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Target;
+import javax.persistence.AttributeConverter;
+import javax.persistence.Entity;
+
+/**
+ * Annotation for {@link Entity} which id is string type and needs an {@link AttributeConverter} for
+ * its VKey.
+ */
+@Target({ElementType.TYPE})
+public @interface WithStringVKey {
+  /**
+   * Sets the suffix of the class name for the {@link AttributeConverter} generated by
+   * StringVKeyProcessor. If not set, the suffix will be the type name of the VKey. Note that the
+   * class name will be "VKeyConverter_" concatenated with the suffix.
+   */
+  String classNameSuffix() default "";
+}

core/src/main/java/google/registry/persistence/converter/VKeyConverter.java

@@ -19,16 +19,16 @@ import javax.annotation.Nullable;
 import javax.persistence.AttributeConverter;
 
 /** Converts VKey to a string column. */
-public abstract class VKeyConverter<T> implements AttributeConverter<VKey<T>, String> {
+public abstract class VKeyConverter<T, C> implements AttributeConverter<VKey<? extends T>, C> {
   @Override
   @Nullable
-  public String convertToDatabaseColumn(@Nullable VKey<T> attribute) {
+  public C convertToDatabaseColumn(@Nullable VKey<? extends T> attribute) {
-    return attribute == null ? null : (String) attribute.getSqlKey();
+    return attribute == null ? null : (C) attribute.getSqlKey();
   }
 
   @Override
   @Nullable
-  public VKey<T> convertToEntityAttribute(@Nullable String dbData) {
+  public VKey<? extends T> convertToEntityAttribute(@Nullable C dbData) {
     return dbData == null ? null : VKey.createSql(getAttributeClass(), dbData);
   }
 

core/src/main/resources/META-INF/persistence.xml

@@ -48,9 +48,11 @@
     <class>google.registry.persistence.converter.StringListConverter</class>
     <class>google.registry.persistence.converter.StringSetConverter</class>
     <class>google.registry.persistence.converter.UpdateAutoTimestampConverter</class>
-    <class>google.registry.persistence.converter.VKeyConverter</class>
     <class>google.registry.persistence.converter.ZonedDateTimeConverter</class>
 
+    <!-- Generated converters for VKey -->
+    <class>google.registry.model.host.VKeyConverter_HostResource</class>
+
     <!-- TODO(weiminyu): check out application-layer validation. -->
     <validation-mode>NONE</validation-mode>
   </persistence-unit>

core/src/test/java/google/registry/persistence/VKeyTest.java

@@ -37,9 +37,10 @@ public class VKeyTest {
 
   @Test
   public void testOptionalAccessors() {
-    VKey<TestObject> key = VKey.create(TestObject.class, null, null);
+    VKey<TestObject> key =
-    assertThat(key.maybeGetSqlKey().isPresent()).isFalse();
+        VKey.create(TestObject.class, "foo", Key.create(TestObject.create("foo")));
-    assertThat(key.maybeGetOfyKey().isPresent()).isFalse();
+    assertThat(key.maybeGetSqlKey().isPresent()).isTrue();
+    assertThat(key.maybeGetOfyKey().isPresent()).isTrue();
 
     Key<TestObject> ofyKey = Key.create(TestObject.create("foo"));
     assertThat(VKey.createOfy(TestObject.class, ofyKey).maybeGetOfyKey().get()).isEqualTo(ofyKey);

core/src/test/java/google/registry/persistence/converter/LongVKeyConverterTest.java

@@ -0,0 +1,65 @@
+// Copyright 2020 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.persistence.converter;
+
+import static com.google.common.truth.Truth.assertThat;
+import static google.registry.persistence.transaction.TransactionManagerFactory.jpaTm;
+
+import google.registry.persistence.VKey;
+import google.registry.persistence.WithLongVKey;
+import google.registry.persistence.transaction.JpaTestRules;
+import google.registry.persistence.transaction.JpaTestRules.JpaUnitTestRule;
+import javax.persistence.Entity;
+import javax.persistence.Id;
+import org.junit.Rule;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.junit.runners.JUnit4;
+
+/** Test SQL persistence of VKey. */
+@RunWith(JUnit4.class)
+public class LongVKeyConverterTest {
+
+  @Rule
+  public final JpaUnitTestRule jpaRule =
+      new JpaTestRules.Builder()
+          .withEntityClass(TestEntity.class, VKeyConverter_LongType.class)
+          .buildUnitTestRule();
+
+  @Test
+  public void testRoundTrip() {
+    TestEntity original = new TestEntity(VKey.createSql(TestEntity.class, 10L));
+    jpaTm().transact(() -> jpaTm().getEntityManager().persist(original));
+
+    TestEntity retrieved =
+        jpaTm().transact(() -> jpaTm().getEntityManager().find(TestEntity.class, "id"));
+    assertThat(retrieved.number.getSqlKey()).isEqualTo(10L);
+  }
+
+  @Entity(name = "TestEntity")
+  @WithLongVKey(classNameSuffix = "LongType")
+  static class TestEntity {
+    @Id String id = "id";
+
+    VKey<TestEntity> number;
+
+    TestEntity(VKey<TestEntity> number) {
+      this.number = number;
+    }
+
+    /** Default constructor, needed for hibernate. */
+    public TestEntity() {}
+  }
+}

core/src/test/java/google/registry/persistence/converter/StringVKeyConverterTest.java

@@ -18,9 +18,9 @@ import static com.google.common.truth.Truth.assertThat;
 import static google.registry.persistence.transaction.TransactionManagerFactory.jpaTm;
 
 import google.registry.persistence.VKey;
+import google.registry.persistence.WithStringVKey;
 import google.registry.persistence.transaction.JpaTestRules;
 import google.registry.persistence.transaction.JpaTestRules.JpaUnitTestRule;
-import javax.persistence.Convert;
 import javax.persistence.Entity;
 import javax.persistence.Id;
 import org.junit.Rule;
@@ -30,13 +30,15 @@ import org.junit.runners.JUnit4;
 
 /** Test SQL persistence of VKey. */
 @RunWith(JUnit4.class)
-public class VKeyConverterTest {
+public class StringVKeyConverterTest {
 
   @Rule
   public final JpaUnitTestRule jpaRule =
-      new JpaTestRules.Builder().withEntityClass(TestEntity.class).buildUnitTestRule();
+      new JpaTestRules.Builder()
+          .withEntityClass(TestEntity.class, VKeyConverter_StringType.class)
+          .buildUnitTestRule();
 
-  public VKeyConverterTest() {}
+  public StringVKeyConverterTest() {}
 
   @Test
   public void testRoundTrip() {
@@ -50,21 +52,11 @@ public class VKeyConverterTest {
     assertThat(retrieved.other.getSqlKey()).isEqualTo("ImSpartacus!");
   }
 
-  static class TestEntityVKeyConverter extends VKeyConverter<TestEntity> {
-
-    @Override
-    protected Class<TestEntity> getAttributeClass() {
-      return TestEntity.class;
-    }
-  }
-
   @Entity(name = "TestEntity")
+  @WithStringVKey(classNameSuffix = "StringType")
   static class TestEntity {
     @Id String id;
 
-    // Specifying "@Converter(autoApply = true) on TestEntityVKeyConverter this doesn't seem to
-    // work.
-    @Convert(converter = TestEntityVKeyConverter.class)
     VKey<TestEntity> other;
 
     TestEntity(String id, VKey<TestEntity> other) {

dependencies.gradle

@@ -78,6 +78,7 @@ ext {
       'com.googlecode.json-simple:json-simple:1.1.1',
       'com.ibm.icu:icu4j:57.1',
       'com.jcraft:jsch:0.1.55',
+      'com.squareup:javapoet:1.12.1',
       'com.sun.activation:javax.activation:1.2.0',
       'com.sun.xml.bind:jaxb-impl:2.2.11',
       'com.sun.xml.bind:jaxb-osgi:2.2.11',

processor/build.gradle

@@ -0,0 +1,25 @@
+// Copyright 2020 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.
+
+plugins {
+    id 'java-library'
+}
+
+dependencies {
+    def deps = rootProject.dependencyMap
+    compile deps['com.google.code.findbugs:jsr305']
+    compile deps['com.google.guava:guava']
+    compile deps['com.squareup:javapoet']
+    compile deps['javax.persistence:javax.persistence-api']
+}

processor/gradle/dependency-locks/annotationProcessor.lockfile

@@ -0,0 +1,24 @@
+# This is a Gradle generated file for dependency locking.
+# Manual edits can break the build and are not advised.
+# This file is expected to be part of source control.
+com.github.kevinstern:software-and-algorithms:1.0
+com.github.stephenc.jcip:jcip-annotations:1.0-1
+com.google.auto:auto-common:0.10
+com.google.code.findbugs:jFormatString:3.0.0
+com.google.code.findbugs:jsr305:3.0.2
+com.google.errorprone:error_prone_annotation:2.3.3
+com.google.errorprone:error_prone_annotations:2.3.3
+com.google.errorprone:error_prone_check_api:2.3.3
+com.google.errorprone:error_prone_core:2.3.3
+com.google.errorprone:error_prone_type_annotations:2.3.3
+com.google.guava:failureaccess:1.0.1
+com.google.guava:guava:27.0.1-jre
+com.google.guava:listenablefuture:9999.0-empty-to-avoid-conflict-with-guava
+com.google.j2objc:j2objc-annotations:1.1
+com.google.protobuf:protobuf-java:3.4.0
+com.googlecode.java-diff-utils:diffutils:1.3.0
+org.checkerframework:checker-qual:2.5.3
+org.checkerframework:dataflow:2.5.3
+org.checkerframework:javacutil:2.5.3
+org.codehaus.mojo:animal-sniffer-annotations:1.17
+org.pcollections:pcollections:2.1.2

processor/gradle/dependency-locks/apt.lockfile

@@ -0,0 +1,3 @@
+# This is a Gradle generated file for dependency locking.
+# Manual edits can break the build and are not advised.
+# This file is expected to be part of source control.

processor/gradle/dependency-locks/archives.lockfile

@@ -0,0 +1,3 @@
+# This is a Gradle generated file for dependency locking.
+# Manual edits can break the build and are not advised.
+# This file is expected to be part of source control.

processor/gradle/dependency-locks/buildscript-classpath.lockfile

@@ -0,0 +1,3 @@
+# This is a Gradle generated file for dependency locking.
+# Manual edits can break the build and are not advised.
+# This file is expected to be part of source control.

processor/gradle/dependency-locks/checkstyle.lockfile

@@ -0,0 +1,18 @@
+# This is a Gradle generated file for dependency locking.
+# Manual edits can break the build and are not advised.
+# This file is expected to be part of source control.
+antlr:antlr:2.7.7
+com.google.code.findbugs:jsr305:3.0.2
+com.google.errorprone:error_prone_annotations:2.3.2
+com.google.guava:failureaccess:1.0.1
+com.google.guava:guava:28.1-jre
+com.google.guava:listenablefuture:9999.0-empty-to-avoid-conflict-with-guava
+com.google.j2objc:j2objc-annotations:1.3
+com.puppycrawl.tools:checkstyle:8.27
+commons-beanutils:commons-beanutils:1.9.4
+commons-collections:commons-collections:3.2.2
+info.picocli:picocli:4.1.1
+net.sf.saxon:Saxon-HE:9.9.1-5
+org.antlr:antlr4-runtime:4.7.2
+org.checkerframework:checker-qual:2.8.1
+org.codehaus.mojo:animal-sniffer-annotations:1.18

processor/gradle/dependency-locks/compile.lockfile

@@ -0,0 +1,12 @@
+# This is a Gradle generated file for dependency locking.
+# Manual edits can break the build and are not advised.
+# This file is expected to be part of source control.
+com.google.code.findbugs:jsr305:3.0.2
+com.google.errorprone:error_prone_annotations:2.3.4
+com.google.guava:failureaccess:1.0.1
+com.google.guava:guava:28.2-jre
+com.google.guava:listenablefuture:9999.0-empty-to-avoid-conflict-with-guava
+com.google.j2objc:j2objc-annotations:1.3
+com.squareup:javapoet:1.12.1
+javax.persistence:javax.persistence-api:2.2
+org.checkerframework:checker-qual:2.10.0

processor/gradle/dependency-locks/compileClasspath.lockfile

@@ -0,0 +1,12 @@
+# This is a Gradle generated file for dependency locking.
+# Manual edits can break the build and are not advised.
+# This file is expected to be part of source control.
+com.google.code.findbugs:jsr305:3.0.2
+com.google.errorprone:error_prone_annotations:2.3.4
+com.google.guava:failureaccess:1.0.1
+com.google.guava:guava:28.2-jre
+com.google.guava:listenablefuture:9999.0-empty-to-avoid-conflict-with-guava
+com.google.j2objc:j2objc-annotations:1.3
+com.squareup:javapoet:1.12.1
+javax.persistence:javax.persistence-api:2.2
+org.checkerframework:checker-qual:2.10.0

processor/gradle/dependency-locks/compileOnly.lockfile

@@ -0,0 +1,3 @@
+# This is a Gradle generated file for dependency locking.
+# Manual edits can break the build and are not advised.
+# This file is expected to be part of source control.

processor/gradle/dependency-locks/default.lockfile

@@ -0,0 +1,12 @@
+# This is a Gradle generated file for dependency locking.
+# Manual edits can break the build and are not advised.
+# This file is expected to be part of source control.
+com.google.code.findbugs:jsr305:3.0.2
+com.google.errorprone:error_prone_annotations:2.3.4
+com.google.guava:failureaccess:1.0.1
+com.google.guava:guava:28.2-jre
+com.google.guava:listenablefuture:9999.0-empty-to-avoid-conflict-with-guava
+com.google.j2objc:j2objc-annotations:1.3
+com.squareup:javapoet:1.12.1
+javax.persistence:javax.persistence-api:2.2
+org.checkerframework:checker-qual:2.10.0

processor/gradle/dependency-locks/deploy_jar.lockfile

@@ -0,0 +1,12 @@
+# This is a Gradle generated file for dependency locking.
+# Manual edits can break the build and are not advised.
+# This file is expected to be part of source control.
+com.google.code.findbugs:jsr305:3.0.2
+com.google.errorprone:error_prone_annotations:2.3.4
+com.google.guava:failureaccess:1.0.1
+com.google.guava:guava:28.2-jre
+com.google.guava:listenablefuture:9999.0-empty-to-avoid-conflict-with-guava
+com.google.j2objc:j2objc-annotations:1.3
+com.squareup:javapoet:1.12.1
+javax.persistence:javax.persistence-api:2.2
+org.checkerframework:checker-qual:2.10.0

processor/gradle/dependency-locks/errorprone.lockfile

@@ -0,0 +1,24 @@
+# This is a Gradle generated file for dependency locking.
+# Manual edits can break the build and are not advised.
+# This file is expected to be part of source control.
+com.github.kevinstern:software-and-algorithms:1.0
+com.github.stephenc.jcip:jcip-annotations:1.0-1
+com.google.auto:auto-common:0.10
+com.google.code.findbugs:jFormatString:3.0.0
+com.google.code.findbugs:jsr305:3.0.2
+com.google.errorprone:error_prone_annotation:2.3.3
+com.google.errorprone:error_prone_annotations:2.3.3
+com.google.errorprone:error_prone_check_api:2.3.3
+com.google.errorprone:error_prone_core:2.3.3
+com.google.errorprone:error_prone_type_annotations:2.3.3
+com.google.guava:failureaccess:1.0.1
+com.google.guava:guava:27.0.1-jre
+com.google.guava:listenablefuture:9999.0-empty-to-avoid-conflict-with-guava
+com.google.j2objc:j2objc-annotations:1.1
+com.google.protobuf:protobuf-java:3.4.0
+com.googlecode.java-diff-utils:diffutils:1.3.0
+org.checkerframework:checker-qual:2.5.3
+org.checkerframework:dataflow:2.5.3
+org.checkerframework:javacutil:2.5.3
+org.codehaus.mojo:animal-sniffer-annotations:1.17
+org.pcollections:pcollections:2.1.2

processor/gradle/dependency-locks/errorproneJavac.lockfile

@@ -0,0 +1,4 @@
+# This is a Gradle generated file for dependency locking.
+# Manual edits can break the build and are not advised.
+# This file is expected to be part of source control.
+com.google.errorprone:javac:9+181-r4173-1

processor/gradle/dependency-locks/jacocoAgent.lockfile

@@ -0,0 +1,4 @@
+# This is a Gradle generated file for dependency locking.
+# Manual edits can break the build and are not advised.
+# This file is expected to be part of source control.
+org.jacoco:org.jacoco.agent:0.8.5

processor/gradle/dependency-locks/jacocoAnt.lockfile

@@ -0,0 +1,11 @@
+# This is a Gradle generated file for dependency locking.
+# Manual edits can break the build and are not advised.
+# This file is expected to be part of source control.
+org.jacoco:org.jacoco.agent:0.8.5
+org.jacoco:org.jacoco.ant:0.8.5
+org.jacoco:org.jacoco.core:0.8.5
+org.jacoco:org.jacoco.report:0.8.5
+org.ow2.asm:asm-analysis:7.2
+org.ow2.asm:asm-commons:7.2
+org.ow2.asm:asm-tree:7.2
+org.ow2.asm:asm:7.2

processor/gradle/dependency-locks/runtime.lockfile

@@ -0,0 +1,12 @@
+# This is a Gradle generated file for dependency locking.
+# Manual edits can break the build and are not advised.
+# This file is expected to be part of source control.
+com.google.code.findbugs:jsr305:3.0.2
+com.google.errorprone:error_prone_annotations:2.3.4
+com.google.guava:failureaccess:1.0.1
+com.google.guava:guava:28.2-jre
+com.google.guava:listenablefuture:9999.0-empty-to-avoid-conflict-with-guava
+com.google.j2objc:j2objc-annotations:1.3
+com.squareup:javapoet:1.12.1
+javax.persistence:javax.persistence-api:2.2
+org.checkerframework:checker-qual:2.10.0

processor/gradle/dependency-locks/runtimeClasspath.lockfile

@@ -0,0 +1,12 @@
+# This is a Gradle generated file for dependency locking.
+# Manual edits can break the build and are not advised.
+# This file is expected to be part of source control.
+com.google.code.findbugs:jsr305:3.0.2
+com.google.errorprone:error_prone_annotations:2.3.4
+com.google.guava:failureaccess:1.0.1
+com.google.guava:guava:28.2-jre
+com.google.guava:listenablefuture:9999.0-empty-to-avoid-conflict-with-guava
+com.google.j2objc:j2objc-annotations:1.3
+com.squareup:javapoet:1.12.1
+javax.persistence:javax.persistence-api:2.2
+org.checkerframework:checker-qual:2.10.0

processor/gradle/dependency-locks/testAnnotationProcessor.lockfile

@@ -0,0 +1,24 @@
+# This is a Gradle generated file for dependency locking.
+# Manual edits can break the build and are not advised.
+# This file is expected to be part of source control.
+com.github.kevinstern:software-and-algorithms:1.0
+com.github.stephenc.jcip:jcip-annotations:1.0-1
+com.google.auto:auto-common:0.10
+com.google.code.findbugs:jFormatString:3.0.0
+com.google.code.findbugs:jsr305:3.0.2
+com.google.errorprone:error_prone_annotation:2.3.3
+com.google.errorprone:error_prone_annotations:2.3.3
+com.google.errorprone:error_prone_check_api:2.3.3
+com.google.errorprone:error_prone_core:2.3.3
+com.google.errorprone:error_prone_type_annotations:2.3.3
+com.google.guava:failureaccess:1.0.1
+com.google.guava:guava:27.0.1-jre
+com.google.guava:listenablefuture:9999.0-empty-to-avoid-conflict-with-guava
+com.google.j2objc:j2objc-annotations:1.1
+com.google.protobuf:protobuf-java:3.4.0
+com.googlecode.java-diff-utils:diffutils:1.3.0
+org.checkerframework:checker-qual:2.5.3
+org.checkerframework:dataflow:2.5.3
+org.checkerframework:javacutil:2.5.3
+org.codehaus.mojo:animal-sniffer-annotations:1.17
+org.pcollections:pcollections:2.1.2

processor/gradle/dependency-locks/testApt.lockfile

@@ -0,0 +1,3 @@
+# This is a Gradle generated file for dependency locking.
+# Manual edits can break the build and are not advised.
+# This file is expected to be part of source control.

processor/gradle/dependency-locks/testCompile.lockfile

@@ -0,0 +1,12 @@
+# This is a Gradle generated file for dependency locking.
+# Manual edits can break the build and are not advised.
+# This file is expected to be part of source control.
+com.google.code.findbugs:jsr305:3.0.2
+com.google.errorprone:error_prone_annotations:2.3.4
+com.google.guava:failureaccess:1.0.1
+com.google.guava:guava:28.2-jre
+com.google.guava:listenablefuture:9999.0-empty-to-avoid-conflict-with-guava
+com.google.j2objc:j2objc-annotations:1.3
+com.squareup:javapoet:1.12.1
+javax.persistence:javax.persistence-api:2.2
+org.checkerframework:checker-qual:2.10.0

processor/gradle/dependency-locks/testCompileClasspath.lockfile

@@ -0,0 +1,12 @@
+# This is a Gradle generated file for dependency locking.
+# Manual edits can break the build and are not advised.
+# This file is expected to be part of source control.
+com.google.code.findbugs:jsr305:3.0.2
+com.google.errorprone:error_prone_annotations:2.3.4
+com.google.guava:failureaccess:1.0.1
+com.google.guava:guava:28.2-jre
+com.google.guava:listenablefuture:9999.0-empty-to-avoid-conflict-with-guava
+com.google.j2objc:j2objc-annotations:1.3
+com.squareup:javapoet:1.12.1
+javax.persistence:javax.persistence-api:2.2
+org.checkerframework:checker-qual:2.10.0

processor/gradle/dependency-locks/testCompileOnly.lockfile

@@ -0,0 +1,3 @@
+# This is a Gradle generated file for dependency locking.
+# Manual edits can break the build and are not advised.
+# This file is expected to be part of source control.

processor/gradle/dependency-locks/testRuntime.lockfile

@@ -0,0 +1,12 @@
+# This is a Gradle generated file for dependency locking.
+# Manual edits can break the build and are not advised.
+# This file is expected to be part of source control.
+com.google.code.findbugs:jsr305:3.0.2
+com.google.errorprone:error_prone_annotations:2.3.4
+com.google.guava:failureaccess:1.0.1
+com.google.guava:guava:28.2-jre
+com.google.guava:listenablefuture:9999.0-empty-to-avoid-conflict-with-guava
+com.google.j2objc:j2objc-annotations:1.3
+com.squareup:javapoet:1.12.1
+javax.persistence:javax.persistence-api:2.2
+org.checkerframework:checker-qual:2.10.0

processor/gradle/dependency-locks/testRuntimeClasspath.lockfile

@@ -0,0 +1,12 @@
+# This is a Gradle generated file for dependency locking.
+# Manual edits can break the build and are not advised.
+# This file is expected to be part of source control.
+com.google.code.findbugs:jsr305:3.0.2
+com.google.errorprone:error_prone_annotations:2.3.4
+com.google.guava:failureaccess:1.0.1
+com.google.guava:guava:28.2-jre
+com.google.guava:listenablefuture:9999.0-empty-to-avoid-conflict-with-guava
+com.google.j2objc:j2objc-annotations:1.3
+com.squareup:javapoet:1.12.1
+javax.persistence:javax.persistence-api:2.2
+org.checkerframework:checker-qual:2.10.0

processor/src/main/java/google/registry/processors/AbstractVKeyProcessor.java

@@ -0,0 +1,160 @@
+// Copyright 2020 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.processors;
+
+import static com.google.common.base.Preconditions.checkState;
+import static com.google.common.collect.ImmutableList.toImmutableList;
+
+import com.squareup.javapoet.AnnotationSpec;
+import com.squareup.javapoet.ClassName;
+import com.squareup.javapoet.JavaFile;
+import com.squareup.javapoet.MethodSpec;
+import com.squareup.javapoet.ParameterizedTypeName;
+import com.squareup.javapoet.TypeName;
+import com.squareup.javapoet.TypeSpec;
+import java.io.IOException;
+import java.io.UncheckedIOException;
+import java.util.List;
+import java.util.Set;
+import javax.annotation.processing.AbstractProcessor;
+import javax.annotation.processing.RoundEnvironment;
+import javax.lang.model.element.AnnotationMirror;
+import javax.lang.model.element.Element;
+import javax.lang.model.element.Modifier;
+import javax.lang.model.element.TypeElement;
+import javax.lang.model.type.DeclaredType;
+import javax.lang.model.type.TypeKind;
+import javax.lang.model.type.TypeMirror;
+import javax.lang.model.util.ElementFilter;
+import javax.lang.model.util.Elements;
+import javax.lang.model.util.Types;
+import javax.persistence.AttributeConverter;
+import javax.persistence.Converter;
+
+/** Abstract processor to generate {@link AttributeConverter} for VKey type. */
+public abstract class AbstractVKeyProcessor extends AbstractProcessor {
+
+  private static final String CONVERTER_CLASS_NAME_TEMP = "VKeyConverter_%s";
+  // The method with same name should be defined in StringVKey and LongVKey
+  private static final String CLASS_NAME_SUFFIX_KEY = "classNameSuffix";
+
+  abstract Class<?> getSqlColumnType();
+
+  abstract String getAnnotationSimpleName();
+
+  @Override
+  public boolean process(Set<? extends TypeElement> annotations, RoundEnvironment roundEnv) {
+    annotations.forEach(
+        vKeyAnnotationType -> {
+          ElementFilter.typesIn(roundEnv.getElementsAnnotatedWith(vKeyAnnotationType))
+              .forEach(
+                  annotatedTypeElement -> {
+                    DeclaredType entityType = getDeclaredType(annotatedTypeElement);
+
+                    List<AnnotationMirror> actualAnnotation =
+                        annotatedTypeElement.getAnnotationMirrors().stream()
+                            .filter(
+                                annotationType ->
+                                    annotationType
+                                        .getAnnotationType()
+                                        .asElement()
+                                        .equals(vKeyAnnotationType))
+                            .collect(toImmutableList());
+                    checkState(
+                        actualAnnotation.size() == 1,
+                        String.format(
+                            "type can have only 1 %s annotation", getAnnotationSimpleName()));
+                    String converterClassNameSuffix =
+                        actualAnnotation.get(0).getElementValues().entrySet().stream()
+                            .filter(
+                                entry ->
+                                    entry
+                                        .getKey()
+                                        .getSimpleName()
+                                        .toString()
+                                        .equals(CLASS_NAME_SUFFIX_KEY))
+                            .map(entry -> ((String) entry.getValue().getValue()).trim())
+                            .findFirst()
+                            .orElse("");
+                    if (converterClassNameSuffix.isEmpty()) {
+                      converterClassNameSuffix =
+                          getTypeUtils().asElement(entityType).getSimpleName().toString();
+                    }
+
+                    try {
+                      createJavaFile(
+                              getPackageName(annotatedTypeElement),
+                              String.format(CONVERTER_CLASS_NAME_TEMP, converterClassNameSuffix),
+                              entityType)
+                          .writeTo(processingEnv.getFiler());
+                    } catch (IOException e) {
+                      throw new UncheckedIOException(e);
+                    }
+                  });
+        });
+    return false;
+  }
+
+  private JavaFile createJavaFile(
+      String packageName, String converterClassName, TypeMirror entityTypeMirror) {
+    TypeName entityType = ClassName.get(entityTypeMirror);
+
+    ParameterizedTypeName attributeConverter =
+        ParameterizedTypeName.get(
+            ClassName.get("google.registry.persistence.converter", "VKeyConverter"),
+            entityType,
+            ClassName.get(getSqlColumnType()));
+
+    MethodSpec getAttributeClass =
+        MethodSpec.methodBuilder("getAttributeClass")
+            .addAnnotation(Override.class)
+            .addModifiers(Modifier.PROTECTED)
+            .returns(
+                ParameterizedTypeName.get(
+                    ClassName.get(Class.class), ClassName.get(entityTypeMirror)))
+            .addStatement("return $T.class", entityType)
+            .build();
+
+    TypeSpec vKeyConverter =
+        TypeSpec.classBuilder(converterClassName)
+            .addAnnotation(
+                AnnotationSpec.builder(ClassName.get(Converter.class))
+                    .addMember("autoApply", "true")
+                    .build())
+            .addModifiers(Modifier.FINAL)
+            .superclass(attributeConverter)
+            .addMethod(getAttributeClass)
+            .build();
+
+    return JavaFile.builder(packageName, vKeyConverter).build();
+  }
+
+  private DeclaredType getDeclaredType(Element element) {
+    checkState(element.asType().getKind() == TypeKind.DECLARED, "element is not a DeclaredType");
+    return (DeclaredType) element.asType();
+  }
+
+  private String getPackageName(Element element) {
+    return getElementUtils().getPackageOf(element).getQualifiedName().toString();
+  }
+
+  private Elements getElementUtils() {
+    return processingEnv.getElementUtils();
+  }
+
+  private Types getTypeUtils() {
+    return processingEnv.getTypeUtils();
+  }
+}

processor/src/main/java/google/registry/processors/LongVKeyProcessor.java

@@ -0,0 +1,37 @@
+// Copyright 2020 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.processors;
+
+import javax.annotation.processing.SupportedAnnotationTypes;
+import javax.annotation.processing.SupportedSourceVersion;
+import javax.lang.model.SourceVersion;
+
+/** Annotation processor for entity that is annotated with WithLongVKey. */
+@SupportedAnnotationTypes("google.registry.persistence.WithLongVKey")
+@SupportedSourceVersion(SourceVersion.RELEASE_8)
+public class LongVKeyProcessor extends AbstractVKeyProcessor {
+
+  private static final String ANNOTATION_SIMPLE_NAME = "WithStringVKey";
+
+  @Override
+  Class<?> getSqlColumnType() {
+    return Long.class;
+  }
+
+  @Override
+  String getAnnotationSimpleName() {
+    return ANNOTATION_SIMPLE_NAME;
+  }
+}

processor/src/main/java/google/registry/processors/StringVKeyProcessor.java

@@ -0,0 +1,37 @@
+// Copyright 2020 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.processors;
+
+import javax.annotation.processing.SupportedAnnotationTypes;
+import javax.annotation.processing.SupportedSourceVersion;
+import javax.lang.model.SourceVersion;
+
+/** Annotation processor for entity that is annotated with WithStringVKey. */
+@SupportedAnnotationTypes("google.registry.persistence.WithStringVKey")
+@SupportedSourceVersion(SourceVersion.RELEASE_8)
+public class StringVKeyProcessor extends AbstractVKeyProcessor {
+
+  private static final String ANNOTATION_SIMPLE_NAME = "WithStringVKey";
+
+  @Override
+  Class<?> getSqlColumnType() {
+    return String.class;
+  }
+
+  @Override
+  String getAnnotationSimpleName() {
+    return ANNOTATION_SIMPLE_NAME;
+  }
+}

processor/src/main/resources/META-INF/services/javax.annotation.processing.Processor

@@ -0,0 +1,2 @@
+google.registry.processors.StringVKeyProcessor
+google.registry.processors.LongVKeyProcessor

settings.gradle

@@ -32,6 +32,7 @@ include 'core'
 include 'db'
 include 'integration'
 include 'networking'
+include 'processor'
 include 'prober'
 include 'proxy'
 include 'util'