| /* |
| * Copyright 2008 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.javac; |
| |
| import com.google.gwt.core.ext.TreeLogger; |
| import com.google.gwt.thirdparty.guava.common.collect.HashMultimap; |
| import com.google.gwt.thirdparty.guava.common.collect.ImmutableList; |
| import com.google.gwt.thirdparty.guava.common.collect.ImmutableSet; |
| import com.google.gwt.thirdparty.guava.common.collect.Multimap; |
| |
| import java.util.Collection; |
| import java.util.HashSet; |
| import java.util.Map; |
| import java.util.Set; |
| |
| /** |
| * Helper class to invalidate units in a set based on errors or references to |
| * other invalidate units. |
| */ |
| public class CompilationUnitInvalidator { |
| |
| /** |
| * Mutates {@code units} by retaining only valid units. A unit is invalid if |
| * it |
| * <ul> |
| * <li>has errors, |
| * <li>depends on a member of {@code validClasses} that has errors, |
| * <li>depends on another member of {@code units} that has errors, or |
| * <li>references a source name that is not provided by a good member of |
| * {@code units} or {@code validClasses}. |
| * </ul> |
| */ |
| public static void retainValidUnits(TreeLogger logger, Collection<CompilationUnit> units, |
| Map<String, CompiledClass> validClasses, CompilationErrorsIndex compilationErrorsIndex) { |
| logger = logger.branch(TreeLogger.TRACE, "Removing invalidated units"); |
| |
| // Build a map of api-refs -> dependent units. |
| // This map excludes refs provided by good validClasses; it only contains |
| // dependencies that need to be provided by members of units. |
| Multimap<String, CompilationUnit> depsNeeded = HashMultimap.create(); |
| |
| // This set contains the source names of types provided by units, and after |
| // initial population, may shrink as problems are discovered in individual |
| // units. |
| Set<String> depsProvided = new HashSet<String>(); |
| |
| // For fast membership checking of the initial set of units |
| Set<CompilationUnit> initialUnits = (units instanceof Set) |
| ? (Set<CompilationUnit>) units |
| : ImmutableSet.<CompilationUnit>copyOf(units); |
| |
| // These are all of the invalid units |
| Set<CompilationUnit> allBrokenUnits = new HashSet<CompilationUnit>(); |
| |
| // Populate depsNeeded, depsProvided, and allBrokenUnits with their initial values. |
| // At first, only compilation units that directly contain an error are known to be |
| // broken, not their dependencies. |
| for (CompilationUnit unit : units) { |
| if (unit.isError()) { |
| // It is bad and can be removed immediately |
| allBrokenUnits.add(unit); |
| } else { |
| // Update set of dependencies the unit provides |
| for (CompiledClass cc : unit.getCompiledClasses()) { |
| depsProvided.add(cc.getSourceName()); |
| } |
| |
| // Update map of dependencies that the unit needs |
| for (String ref : unit.getDependencies().getApiRefs()) { |
| // Check validClasses |
| CompiledClass compiledClass = validClasses.get(ref); |
| if ((compiledClass == null) |
| || compiledClass.getUnit().isError() |
| || initialUnits.contains(compiledClass.getUnit())) { |
| // we'll put this into the double-check pot |
| depsNeeded.put(ref, unit); |
| } |
| } |
| } |
| } |
| |
| // Repeatedly remove CompilationUnits that have a dependency that's known to |
| // be broken. |
| Multimap<String, CompilationUnit> missing; |
| do { |
| // Find the missing deps for this pass |
| missing = HashMultimap.create(); |
| missing.putAll(depsNeeded); |
| missing.keySet().removeAll(depsProvided); |
| |
| // Process the units with missing deps |
| for (Map.Entry<String, CompilationUnit> brokenEntry : missing.entries()) { |
| CompilationUnit brokenUnit = brokenEntry.getValue(); |
| |
| // Modify depsProvided for newly discovered broken units |
| // (side-effect add in 'if' condition) |
| if (allBrokenUnits.add(brokenUnit)) { |
| // Remove the broken unit from the provides set |
| for (CompiledClass cc : brokenUnit.getCompiledClasses()) { |
| depsProvided.remove(cc.getSourceName()); |
| } |
| |
| // Log it to maintain some logging compatibility with prior versions |
| // of this class. |
| TreeLogger branch = logger.branch(TreeLogger.DEBUG, |
| "Compilation unit '" + brokenUnit |
| + "' is removed due to invalid reference(s):"); |
| branch.log(TreeLogger.DEBUG, brokenEntry.getKey()); |
| // Record inferred errors resulting from references to broken types so that accurate |
| // errors chains can be reported. |
| compilationErrorsIndex.add(brokenUnit.getTypeName(), brokenUnit.getResourceLocation(), |
| brokenUnit.getDependencies().getApiRefs(), |
| ImmutableList.of(brokenEntry.getKey() + " cannot be resolved to a type")); |
| } |
| } |
| |
| // Having found and removed some units with missing deps, remove their |
| // needs. |
| depsNeeded.keySet().removeAll(missing.keySet()); |
| } while (!missing.isEmpty()); |
| |
| units.removeAll(allBrokenUnits); |
| } |
| } |