1 /* 2 * Copyright (C) 2014 The Dagger Authors. 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package dagger.internal; 18 19 import static dagger.internal.Preconditions.checkNotNull; 20 import static dagger.internal.Providers.asDaggerProvider; 21 22 /** 23 * A DelegateFactory that is used to stitch Provider/Lazy indirection based dependency cycles. 24 * 25 * @since 2.0.1 26 */ 27 public final class DelegateFactory<T> implements Factory<T> { 28 private Provider<T> delegate; 29 30 @Override get()31 public T get() { 32 if (delegate == null) { 33 throw new IllegalStateException(); 34 } 35 return delegate.get(); 36 } 37 38 // TODO(ronshapiro): remove this once we can reasonably expect generated code is no longer using 39 // this method 40 @Deprecated setDelegatedProvider(Provider<T> delegate)41 public void setDelegatedProvider(Provider<T> delegate) { 42 setDelegate(this, delegate); 43 } 44 45 /** 46 * Legacy javax version of the method to support libraries compiled with an older version of 47 * Dagger. Do not use directly. 48 */ 49 @Deprecated setDelegatedProvider(javax.inject.Provider<T> delegate)50 public void setDelegatedProvider(javax.inject.Provider<T> delegate) { 51 setDelegatedProvider(asDaggerProvider(delegate)); 52 } 53 54 /** 55 * Sets {@code delegateFactory}'s delegate provider to {@code delegate}. 56 * 57 * <p>{@code delegateFactory} must be an instance of {@link DelegateFactory}, otherwise this 58 * method will throw a {@link ClassCastException}. 59 */ setDelegate(Provider<T> delegateFactory, Provider<T> delegate)60 public static <T> void setDelegate(Provider<T> delegateFactory, Provider<T> delegate) { 61 DelegateFactory<T> asDelegateFactory = (DelegateFactory<T>) delegateFactory; 62 setDelegateInternal(asDelegateFactory, delegate); 63 } 64 65 /** 66 * Legacy javax version of the method to support libraries compiled with an older version of 67 * Dagger. Do not use directly. 68 */ 69 @Deprecated setDelegate( javax.inject.Provider<T> delegateFactory, javax.inject.Provider<T> delegate)70 public static <T> void setDelegate( 71 javax.inject.Provider<T> delegateFactory, javax.inject.Provider<T> delegate) { 72 DelegateFactory<T> asDelegateFactory = (DelegateFactory<T>) delegateFactory; 73 setDelegateInternal(asDelegateFactory, asDaggerProvider(delegate)); 74 } 75 setDelegateInternal( DelegateFactory<T> delegateFactory, Provider<T> delegate)76 private static <T> void setDelegateInternal( 77 DelegateFactory<T> delegateFactory, Provider<T> delegate) { 78 checkNotNull(delegate); 79 if (delegateFactory.delegate != null) { 80 throw new IllegalStateException(); 81 } 82 delegateFactory.delegate = delegate; 83 } 84 85 /** 86 * Returns the factory's delegate. 87 * 88 * @throws NullPointerException if the delegate has not been set 89 */ getDelegate()90 Provider<T> getDelegate() { 91 return checkNotNull(delegate); 92 } 93 } 94