| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you 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 org.apache.cassandra.config; |
| |
| import java.lang.reflect.Field; |
| import java.util.ArrayList; |
| import java.util.Collections; |
| import java.util.HashMap; |
| import java.util.HashSet; |
| import java.util.List; |
| import java.util.Map; |
| import java.util.Set; |
| |
| import org.apache.cassandra.exceptions.ConfigurationException; |
| |
| public final class Replacements |
| { |
| private Replacements() |
| { |
| } |
| |
| /** |
| * @param klass to get replacements for |
| * @return map of old names and replacements needed. |
| */ |
| public static Map<Class<? extends Object>, Map<String, Replacement>> getNameReplacements(Class<? extends Object> klass) |
| { |
| List<Replacement> replacements = getReplacementsRecursive(klass); |
| Map<Class<?>, Map<String, Replacement>> objectOldNames = new HashMap<>(); |
| for (Replacement r : replacements) |
| { |
| Map<String, Replacement> oldNames = objectOldNames.computeIfAbsent(r.parent, ignore -> new HashMap<>()); |
| if (!oldNames.containsKey(r.oldName)) |
| oldNames.put(r.oldName, r); |
| else |
| { |
| throw new ConfigurationException("Invalid annotations, you have more than one @Replaces annotation in " + |
| "Config class with same old name(" + r.oldName + ") defined."); |
| } |
| } |
| return objectOldNames; |
| } |
| |
| /** |
| * @param klass to get replacements for |
| * @return map of old names and replacements needed. |
| */ |
| private static List<Replacement> getReplacementsRecursive(Class<?> klass) |
| { |
| Set<Class<?>> seen = new HashSet<>(); // to make sure not to process the same type twice |
| List<Replacement> accum = new ArrayList<>(); |
| getReplacementsRecursive(seen, accum, klass); |
| return accum.isEmpty() ? Collections.emptyList() : accum; |
| } |
| |
| private static void getReplacementsRecursive(Set<Class<?>> seen, |
| List<Replacement> accum, |
| Class<?> klass) |
| { |
| accum.addAll(getReplacements(klass)); |
| for (Field field : klass.getDeclaredFields()) |
| { |
| if (seen.add(field.getType())) |
| { |
| // first time looking at this type, walk it |
| getReplacementsRecursive(seen, accum, field.getType()); |
| } |
| } |
| } |
| |
| private static List<Replacement> getReplacements(Class<?> klass) |
| { |
| List<Replacement> replacements = new ArrayList<>(); |
| for (Field field : klass.getDeclaredFields()) |
| { |
| String newName = field.getName(); |
| Class<?> newType = field.getType(); |
| final ReplacesList[] byType = field.getAnnotationsByType(ReplacesList.class); |
| if (byType == null || byType.length == 0) |
| { |
| Replaces r = field.getAnnotation(Replaces.class); |
| if (r != null) |
| addReplacement(klass, replacements, newName, newType, r); |
| } |
| else |
| { |
| for (ReplacesList replacesList : byType) |
| for (Replaces r : replacesList.value()) |
| addReplacement(klass, replacements, newName, newType, r); |
| } |
| } |
| return replacements.isEmpty() ? Collections.emptyList() : replacements; |
| } |
| |
| private static void addReplacement(Class<?> klass, |
| List<Replacement> replacements, |
| String newName, Class<?> newType, |
| Replaces r) |
| { |
| String oldName = r.oldName(); |
| |
| boolean deprecated = r.deprecated(); |
| |
| Class<?> oldType = r.converter().getOldType(); |
| if (oldType == null) |
| oldType = newType; |
| Class<?> expectedNewType = r.converter().getNewType(); |
| if (expectedNewType != null) |
| assert expectedNewType.equals(newType) : String.format("Converter is expected to return %s but %s#%s expects %s", expectedNewType, klass, newName, newType); |
| |
| replacements.add(new Replacement(klass, oldName, oldType, newName, r.converter(), deprecated)); |
| } |
| } |