| /* |
| * Copyright (c) 2014, the Dart project authors. |
| * |
| * Licensed under the Eclipse Public License v1.0 (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.eclipse.org/legal/epl-v10.html |
| * |
| * 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.google.dart.engine.internal.index.file; |
| |
| import com.google.common.annotations.VisibleForTesting; |
| import com.google.common.collect.Lists; |
| import com.google.common.collect.Maps; |
| |
| import java.util.List; |
| import java.util.Map; |
| |
| /** |
| * A helper that encodes/decodes {@link String}s from/to integers. |
| * |
| * @coverage dart.engine.index |
| */ |
| public class StringCodec { |
| /** |
| * A table mapping names to their unique indices. |
| */ |
| private final Map<String, Integer> nameToIndex = Maps.newHashMap(); |
| |
| /** |
| * A table mapping indices to the corresponding strings. |
| */ |
| private final List<String> indexToName = Lists.newArrayList(); |
| |
| /** |
| * Returns the {@link String} that corresponds to the given index. |
| */ |
| public String decode(int index) { |
| return indexToName.get(index); |
| } |
| |
| /** |
| * Returns an unique index for the given {@link String}. |
| */ |
| public int encode(String name) { |
| Integer index = nameToIndex.get(name); |
| if (index == null) { |
| index = indexToName.size(); |
| nameToIndex.put(name, index); |
| indexToName.add(name); |
| } |
| return index; |
| } |
| |
| @VisibleForTesting |
| public Map<String, Integer> getNameToIndex() { |
| return nameToIndex; |
| } |
| } |