/*
* Copyright 2003-2015 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 jetbrains.mps.generator.impl.dependencies;
import org.jetbrains.annotations.Nullable;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Map;
import java.util.Set;
/**
* Don't want to use <code>jetbrains.mps.util.Interner</code> as it's an overkill for our single-threaded case, I don't like its name, and perhaps
* I'll have to intern other objects here (as SNodeId or SModelReference).
* @author Artem Tikhomirov
*/
final class Intern {
private final Map<String, String> myStrings = new HashMap<String, String>(256);
@Nullable
public String value(@Nullable String origin) {
if (origin == null) {
return null;
}
String cached = myStrings.get(origin);
if (cached != null) {
return cached;
}
myStrings.put(origin, origin);
return origin;
}
}