/*
* Copyright 2000-2015 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 com.intellij.util.containers;
import gnu.trove.TObjectHashingStrategy;
import org.jetbrains.annotations.NotNull;
import java.util.Set;
/**
* Allow to reuse structurally equal objects to avoid memory being wasted on them. Note: objects are cached inside
* and on hard references, so even the ones that are not used anymore will be still present in the memory.
*
* @see WeakInterner
* @author peter
*/
public class Interner<T> {
private final OpenTHashSet<T> mySet;
public Interner() {
mySet = new OpenTHashSet<T>();
}
public Interner(@NotNull TObjectHashingStrategy<T> strategy) {
mySet = new OpenTHashSet<T>(strategy);
}
@NotNull
public T intern(@NotNull T name) {
T interned = mySet.get(name);
if (interned != null) {
return interned;
}
boolean added = mySet.add(name);
assert added;
return name;
}
public void clear() {
mySet.clear();
}
@NotNull
public Set<T> getValues() {
return mySet;
}
}