| /* |
| * Copyright 2014 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.resources.gss; |
| |
| import com.google.gwt.core.ext.typeinfo.JClassType; |
| import com.google.gwt.resources.rg.GssResourceGenerator; |
| import com.google.gwt.thirdparty.common.css.compiler.ast.CssClassSelectorNode; |
| import com.google.gwt.thirdparty.common.css.compiler.ast.CssTree; |
| import com.google.gwt.thirdparty.common.css.compiler.ast.DefaultTreeVisitor; |
| import com.google.gwt.thirdparty.guava.common.base.Preconditions; |
| |
| import java.util.HashSet; |
| import java.util.Set; |
| import java.util.SortedSet; |
| import java.util.TreeSet; |
| |
| /** |
| * Collect all CSS class names in a stylesheet. |
| */ |
| public class ClassNamesCollector extends DefaultTreeVisitor { |
| private Set<String> classNames; |
| private SortedSet<String> excludedPrefixes; |
| |
| /** |
| * Extract all CSS class names in the provided stylesheet. |
| */ |
| public Set<String> getClassNames(CssTree tree) { |
| return getClassNames(tree, new HashSet<JClassType>()); |
| } |
| |
| /** |
| * Extract all CSS class names in the provided stylesheet, modulo those |
| * imported from another context. |
| */ |
| public Set<String> getClassNames(CssTree tree, Set<JClassType> imports) { |
| Preconditions.checkNotNull(tree, "tree cannot be null"); |
| Preconditions.checkNotNull(imports, "imports set cannot be null"); |
| |
| classNames = new HashSet<String>(); |
| excludedPrefixes = new TreeSet<String>(); |
| |
| for (JClassType importedType : imports) { |
| excludedPrefixes.add(GssResourceGenerator.getImportPrefix(importedType)); |
| } |
| |
| tree.getVisitController().startVisit(this); |
| |
| return classNames; |
| } |
| |
| @Override |
| public boolean enterClassSelector(CssClassSelectorNode classSelector) { |
| String className = classSelector.getRefinerName(); |
| |
| if (!isImportedClass(className)) { |
| classNames.add(className); |
| } |
| |
| return false; |
| } |
| |
| private boolean isImportedClass(String className) { |
| SortedSet<String> lowerPrefixes = excludedPrefixes.headSet(className); |
| |
| return !lowerPrefixes.isEmpty() && className.startsWith(lowerPrefixes.last()); |
| } |
| } |