| /* |
| * Copyright (C) 2010 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.inject.multibindings; |
| |
| import com.google.inject.Binding; |
| import com.google.inject.Key; |
| import com.google.inject.TypeLiteral; |
| import com.google.inject.spi.Element; |
| import com.google.inject.spi.Elements; |
| import java.util.List; |
| import java.util.Map; |
| |
| /** |
| * A binding for a MapBinder. |
| * |
| * <p>Although MapBinders may be injected through a variety of generic types (Map<K, V>, Map |
| * <K, Provider<V>>, Map<K, Set<V>>, Map<K, Set< Provider<V>>, and even |
| * Set<Map.Entry<K, Provider<V>>), a MapBinderBinding exists only on the Binding associated |
| * with the Map<K, V> key. Other bindings can be validated to be derived from this |
| * MapBinderBinding using {@link #containsElement(Element)}. |
| * |
| * @param <T> The fully qualified type of the map, including Map. For example: <code> |
| * MapBinderBinding<Map<String, Snack>></code> |
| * @since 3.0 |
| * @author sameb@google.com (Sam Berlin) |
| */ |
| public interface MapBinderBinding<T> { |
| |
| /** Returns the {@link Key} for the map. */ |
| Key<T> getMapKey(); |
| |
| /** |
| * Returns the TypeLiteral describing the keys of the map. |
| * |
| * <p>The TypeLiteral will always match the type Map's generic type. For example, if getMapKey |
| * returns a key of <code>Map<String, Snack></code>, then this will always return a <code> |
| * TypeLiteral<String></code>. |
| */ |
| TypeLiteral<?> getKeyTypeLiteral(); |
| |
| /** |
| * Returns the TypeLiteral describing the values of the map. |
| * |
| * <p>The TypeLiteral will always match the type Map's generic type. For example, if getMapKey |
| * returns a key of <code>Map<String, Snack></code>, then this will always return a <code> |
| * TypeLiteral<Snack></code>. |
| */ |
| TypeLiteral<?> getValueTypeLiteral(); |
| |
| /** |
| * Returns all entries in the Map. The returned list of Map.Entries contains the key and a binding |
| * to the value. Duplicate keys or values will exist as separate Map.Entries in the returned list. |
| * This is only supported on bindings returned from an injector. This will throw {@link |
| * UnsupportedOperationException} if it is called on an element retrieved from {@link |
| * Elements#getElements}. |
| * |
| * <p>The elements will always match the type Map's generic type. For example, if getMapKey |
| * returns a key of <code>Map<String, Snack></code>, then this will always return a list of |
| * type <code>List<Map.Entry<String, Binding<Snack>>></code>. |
| */ |
| List<Map.Entry<?, Binding<?>>> getEntries(); |
| |
| /** |
| * Similar to {@link #getEntries()}, but can be used on a MapBinderBinding retrieved from {@link |
| * Elements#getElements}. |
| * |
| * <p>One way to use this is to pass in the results of {@link Elements#getElements} as the {@code |
| * elements} parameter. |
| * |
| * <p>This differs from {@link #getEntries()} in that it will return duplicates if they are |
| * present in the {@code elements} passed in. This does not run the normal Guice de-duplication |
| * that {@link #getEntries()} does. |
| * |
| * @throws IllegalArgumentException if the provided elements contain partial map entries. If the |
| * elements come from {@link Elements#getElements} on a module with a MapBinder, there will be |
| * a 1:1 relationship and no exception will be thrown. |
| * @since 4.2 |
| */ |
| List<Map.Entry<?, Binding<?>>> getEntries(Iterable<? extends Element> elements); |
| |
| /** |
| * Returns true if the MapBinder permits duplicates. This is only supported on bindings returned |
| * from an injector. This will throw {@link UnsupportedOperationException} if it is called on a |
| * MapBinderBinding retrieved from {@link Elements#getElements}. |
| */ |
| boolean permitsDuplicates(); |
| |
| /** |
| * Returns true if this MapBinder contains the given Element in order to build the map or uses the |
| * given Element in order to support building and injecting the map. This will work for |
| * MapBinderBindings retrieved from an injector and {@link Elements#getElements}. Usually this is |
| * only necessary if you are working with elements retrieved from modules (without an Injector), |
| * otherwise {@link #getEntries} and {@link #permitsDuplicates} are better options. |
| * |
| * <p>If you need to introspect the details of the map, such as the keys, values or if it permits |
| * duplicates, it is necessary to pass the elements through an Injector and use {@link |
| * #getEntries()} and {@link #permitsDuplicates()}. |
| */ |
| boolean containsElement(Element element); |
| } |