| /* |
| * Copyright (C) 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.gson; |
| |
| import java.lang.reflect.ParameterizedType; |
| import java.lang.reflect.Type; |
| import java.util.Collection; |
| import java.util.HashMap; |
| import java.util.Map; |
| import java.util.Set; |
| import java.util.logging.Level; |
| |
| /** |
| * A map that provides ability to associate handlers for a specific type or all of its sub-types |
| * |
| * @author Inderjeet Singh |
| * @author Joel Leitch |
| * |
| * @param <T> The handler that will be looked up by type |
| */ |
| final class ParameterizedTypeHandlerMap<T> { |
| |
| private final Map<Type, T> map = new HashMap<Type, T>(); |
| private boolean modifiable = true; |
| |
| public synchronized void register(Type typeOfT, T value) { |
| if (!modifiable) { |
| throw new IllegalStateException("Attempted to modify an unmodifiable map."); |
| } |
| if (hasSpecificHandlerFor(typeOfT)) { |
| Gson.logger.log(Level.WARNING, "Overriding the existing type handler for " + typeOfT); |
| } |
| map.put(typeOfT, value); |
| } |
| |
| public synchronized void registerIfAbsent(ParameterizedTypeHandlerMap<T> other) { |
| if (!modifiable) { |
| throw new IllegalStateException("Attempted to modify an unmodifiable map."); |
| } |
| for (Map.Entry<Type, T> entry : other.entrySet()) { |
| if (!map.containsKey(entry.getKey())) { |
| register(entry.getKey(), entry.getValue()); |
| } |
| } |
| } |
| |
| public synchronized void makeUnmodifiable() { |
| modifiable = false; |
| } |
| |
| public synchronized T getHandlerFor(Type type) { |
| T handler = getRawHandlerFor(type); |
| Type rawType = type; |
| if (handler == null && type instanceof ParameterizedType) { |
| // a handler for a non-generic version may be registered, so use that |
| rawType = ((ParameterizedType)type).getRawType(); |
| handler = map.get(rawType); |
| } |
| |
| // Check for map or collection |
| if (handler == null) { |
| if (rawType instanceof Class) { |
| Class<?> rawClass = (Class<?>) rawType; |
| if (Map.class.isAssignableFrom(rawClass)) { |
| handler = map.get(Map.class); |
| } else if (Collection.class.isAssignableFrom(rawClass)) { |
| handler = map.get(Collection.class); |
| } else if (Enum.class.isAssignableFrom(rawClass)) { |
| handler = map.get(Enum.class); |
| } |
| } |
| } |
| return handler; |
| } |
| |
| private synchronized T getRawHandlerFor(Type type) { |
| if (type instanceof Map) { |
| return map.get(Map.class); |
| } else if (type instanceof Collection) { |
| return map.get(Collection.class); |
| } else { |
| T handler = map.get(type); |
| if (handler == null) { |
| Class<?> rawClass = TypeUtils.toRawClass(type); |
| if (rawClass != type) { |
| handler = getHandlerFor(rawClass); |
| } |
| } |
| return handler; |
| } |
| } |
| |
| public synchronized boolean hasAnyHandlerFor(Type type) { |
| return getHandlerFor(type) != null; |
| } |
| |
| public synchronized boolean hasSpecificHandlerFor(Type type) { |
| return map.containsKey(type); |
| } |
| |
| public synchronized ParameterizedTypeHandlerMap<T> copyOf() { |
| ParameterizedTypeHandlerMap<T> copy = new ParameterizedTypeHandlerMap<T>(); |
| for (Map.Entry<Type, T> entry : map.entrySet()) { |
| copy.register(entry.getKey(), entry.getValue()); |
| } |
| return copy; |
| } |
| |
| public synchronized Set<Map.Entry<Type, T>> entrySet() { |
| return map.entrySet(); |
| } |
| |
| @Override |
| public String toString() { |
| StringBuilder sb = new StringBuilder("{"); |
| boolean first = true; |
| for (Map.Entry<Type, T> entry : map.entrySet()) { |
| if (first) { |
| first = false; |
| } else { |
| sb.append(','); |
| } |
| sb.append(typeToString(entry.getKey())).append(':'); |
| sb.append(entry.getValue()); |
| } |
| return sb.toString(); |
| } |
| |
| private String typeToString(Type type) { |
| return TypeUtils.toRawClass(type).getSimpleName(); |
| } |
| } |