IndexId as a class, not an interface (immutability of getName() method)

java/java-tests/testSrc/com/intellij/index/StringIndex.java

@@ -18,7 +18,6 @@ package com.intellij.index;
 import com.intellij.openapi.progress.ProgressManager;
 import com.intellij.util.containers.ContainerUtil;
 import com.intellij.util.indexing.*;
-import com.intellij.util.indexing.impl.BasicIndexId;
 import com.intellij.util.indexing.impl.IndexStorage;
 import com.intellij.util.indexing.impl.MapBasedForwardIndex;
 import com.intellij.util.indexing.impl.MapReduceIndex;
@@ -48,7 +47,7 @@ public class StringIndex {
                      final PersistentHashMap<Integer, Collection<String>> inputIndex,
                      boolean failOnRebuildRequest)
     throws IOException {
-    BasicIndexId<String, String> id = BasicIndexId.create(testName + "string_index");
+    IndexId<String, String> id = IndexId.create(testName + "string_index");
     IndexExtension<String, String, PathContentPair> extension = new IndexExtension<String, String, PathContentPair>() {
       @NotNull
       @Override

jps/jps-builders/src/org/jetbrains/jps/backwardRefs/index/CompilerIndices.java

@@ -17,7 +17,6 @@ package org.jetbrains.jps.backwardRefs.index;
 
 import com.intellij.openapi.util.io.DataInputOutputUtilRt;
 import com.intellij.util.indexing.*;
-import com.intellij.util.indexing.impl.BasicIndexId;
 import com.intellij.util.io.DataExternalizer;
 import com.intellij.util.io.DataInputOutputUtil;
 import com.intellij.util.io.KeyDescriptor;
@@ -38,10 +37,10 @@ public class CompilerIndices {
   //TODO manage version separately
   public final static int VERSION = 4;
 
-  public final static IndexId<LightRef, Integer> BACK_USAGES = BasicIndexId.create("back.refs");
-  public final static IndexId<LightRef, Collection<LightRef>> BACK_HIERARCHY = BasicIndexId.create("back.hierarchy");
-  public final static IndexId<LightRef, Void> BACK_CLASS_DEF = BasicIndexId.create("back.class.def");
-  public final static IndexId<SignatureData, Collection<LightRef>> BACK_MEMBER_SIGN = BasicIndexId.create("back.member.sign");
+  public final static IndexId<LightRef, Integer> BACK_USAGES = IndexId.create("back.refs");
+  public final static IndexId<LightRef, Collection<LightRef>> BACK_HIERARCHY = IndexId.create("back.hierarchy");
+  public final static IndexId<LightRef, Void> BACK_CLASS_DEF = IndexId.create("back.class.def");
+  public final static IndexId<SignatureData, Collection<LightRef>> BACK_MEMBER_SIGN = IndexId.create("back.member.sign");
 
   public static List<IndexExtension<?, ?, CompiledFileData>> getIndices() {
     return Arrays.asList(createBackwardClassDefinitionExtension(),

platform/core-api/src/com/intellij/util/indexing/ID.java

@@ -31,12 +31,11 @@ import java.io.*;
  * @author Eugene Zhuravlev
  *         Date: Feb 12, 2008
  */
-public class ID<K, V> implements IndexId<K,V> {
+public class ID<K, V> extends IndexId<K,V> {
   private static final ConcurrentIntObjectMap<ID> ourRegistry = ContainerUtil.createConcurrentIntObjectMap();
   private static final TObjectIntHashMap<String> ourNameToIdRegistry = new TObjectIntHashMap<String>();
   static final int MAX_NUMBER_OF_INDICES = Short.MAX_VALUE;
 
-  private final String myName;
   private final short myUniqueId;
 
   static {
@@ -77,19 +76,13 @@ public class ID<K, V> implements IndexId<K,V> {
     }
   }
 
-  @NotNull
-  @Override
-  public String getName() {
-    return myName;
-  }
-
   private static File getEnumFile() {
     final File indexFolder = PathManager.getIndexRoot();
     return new File(indexFolder, "indices.enum");
   }
 
   protected ID(String name) {
-    myName = name;
+    super(name);
     myUniqueId = stringToId(name);
 
     final ID old = ourRegistry.put(myUniqueId, this);

platform/util/src/com/intellij/util/indexing/IndexId.java

@@ -18,10 +18,36 @@ package com.intellij.util.indexing;
 import org.jetbrains.annotations.ApiStatus;
 import org.jetbrains.annotations.NotNull;
 
-@SuppressWarnings("unused")
 @ApiStatus.Experimental
-public interface IndexId<K, V> {
+public class IndexId<K, V> {
+  @NotNull
+  private final String myName;
+
+  protected IndexId(@NotNull String name) {myName = name;}
 
   @NotNull
-  String getName();
+  public final String getName() {
+    return myName;
+  }
+
+  @Override
+  public boolean equals(Object o) {
+    if (this == o) return true;
+    if (o == null || getClass() != o.getClass()) return false;
+
+    IndexId<?, ?> id = (IndexId<?, ?>)o;
+
+    if (!myName.equals(id.myName)) return false;
+
+    return true;
+  }
+
+  @Override
+  public int hashCode() {
+    return myName.hashCode();
+  }
+
+  public static <K, V> IndexId<K, V> create(String name) {
+    return new IndexId<K, V>(name);
+  }
 }

platform/util/src/com/intellij/util/indexing/impl/BasicIndexId.java

@@ -1,55 +0,0 @@
-/*
- * Copyright 2000-2017 JetBrains s.r.o.
- *
- * 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.intellij.util.indexing.impl;
-
-import com.intellij.util.indexing.IndexId;
-import org.jetbrains.annotations.ApiStatus;
-import org.jetbrains.annotations.NotNull;
-
-@ApiStatus.Experimental
-public class BasicIndexId<K, V> implements IndexId<K,V> {
-  @NotNull
-  private final String myName;
-
-  private BasicIndexId(@NotNull String name) {myName = name;}
-
-  @NotNull
-  @Override
-  public String getName() {
-    return myName;
-  }
-
-  @Override
-  public boolean equals(Object o) {
-    if (this == o) return true;
-    if (o == null || getClass() != o.getClass()) return false;
-
-    BasicIndexId<?, ?> id = (BasicIndexId<?, ?>)o;
-
-    if (!myName.equals(id.myName)) return false;
-
-    return true;
-  }
-
-  @Override
-  public int hashCode() {
-    return myName.hashCode();
-  }
-
-  public static <K, V> BasicIndexId<K, V> create(String name) {
-    return new BasicIndexId<K, V>(name);
-  }
-}

platform/vcs-log/impl/src/com/intellij/vcs/log/data/index/VcsLogFullDetailsIndex.java

@@ -59,7 +59,7 @@ public class VcsLogFullDetailsIndex<T> implements Disposable {
                                 @NotNull FatalErrorHandler fatalErrorHandler,
                                 @NotNull Disposable disposableParent)
     throws IOException {
-    myID = BasicIndexId.create(name);
+    myID = IndexId.create(name);
     myName = name;
     myLogId = logId;
     myIndexer = indexer;