| /* |
| * Copyright 2007 Google Inc. |
| * |
| * 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.google.gwt.dev.generator; |
| |
| import java.util.Collection; |
| import java.util.HashSet; |
| import java.util.Set; |
| |
| /** |
| * Generates unqiue identifiers. Use this class to avoid generating conflicting |
| * names with user code. This class isn't smart enough to know about scopes |
| * (which isn't generally a problem for generators in any case). |
| */ |
| public class NameFactory { |
| |
| private final Set<String> usedNames = new HashSet<String>(); |
| |
| /** |
| * Creates a new <code>NameFactory</code> that knows about |
| * <code>existingNames</code>. |
| * |
| * @param existingNames a list of names that may be <code>null</code>. |
| */ |
| public NameFactory(Collection<String> existingNames) { |
| if (existingNames == null) { |
| return; |
| } |
| usedNames.addAll(existingNames); |
| } |
| |
| /** |
| * Creates a new <code>NameFactory</code> that doesn't know about any |
| * existing names. |
| */ |
| public NameFactory() { |
| this(null); |
| } |
| |
| /** |
| * Reserves a known name. Asserts that the name is not already in this set. |
| * |
| * @param name a not <code>null</code> name |
| */ |
| public void addName(String name) { |
| assert !usedNames.contains(name); |
| usedNames.add(name); |
| } |
| |
| /** |
| * Creates a new unique name based off of <code>name</code> and adds it to |
| * the list of known names. |
| * |
| * @param name a not <code>null</code> name to base the new unique name from |
| * @return a new unique, not <code>null</code> name. This name may be |
| * possibly identical to <code>name</code>. |
| */ |
| public String createName(String name) { |
| String newName = name; |
| |
| for (int count = 0; true; ++count) { |
| if (usedNames.contains(newName)) { |
| newName = name + count; |
| } else { |
| usedNames.add(newName); |
| return newName; |
| } |
| } |
| } |
| } |