/*
* Copyright 2003-2016 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.template;
import org.jetbrains.annotations.NotNull;
import java.util.concurrent.atomic.AtomicInteger;
/**
* Tracks visibility context of a variable name, produce name unique in the context.
* Not thread-safe, deemed for use from single thread. The only non-safe operation is assign/access new name, could be guarded, if necessary.
*
* @author Artem Tikhomirov
*/
public final class VariableNameSource {
private final String myBaseName;
private final String myName;
private String myNewName;
private final AtomicInteger myCounter;
public VariableNameSource(@NotNull String baseName) {
this(baseName, new AtomicInteger(0), baseName);
}
public VariableNameSource(@NotNull String baseName, @NotNull AtomicInteger counter) {
this(baseName, counter, baseName);
}
public VariableNameSource(@NotNull String baseName, @NotNull AtomicInteger counter, @NotNull String actualName) {
myBaseName = baseName;
myName = actualName;
myCounter = counter;
}
/**
* @return name this source got at construction time, never {@code null}
*/
public String getActualName() {
return myName;
}
/**
* @return name latest created with a {@link #newName()} operation, or {@link #getActualName() actual name} if no new name was assigned, never {@code null}
*/
public String getNewName() {
if (myNewName != null) {
return myNewName;
}
return myName;
}
public boolean hasNewName() {
return myNewName != null;
}
/**
* Construct and record new variable name, overriding previous one (i.e. result of preceding {@link #newName()} call).
* @return newly constructed name, never {@code null}
*/
public String newName() {
myNewName = myBaseName + myCounter.incrementAndGet();
return myNewName;
}
/**
* @return name source with {@link #getNewName()} value of the current source as its {@link #getActualName()}.
*/
public VariableNameSource next() {
return new VariableNameSource(myBaseName, myCounter, getNewName());
}
}