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 import org.jspecify.annotations.Nullable; 23 24 /** 25 * A DelegateFactory that is used to stitch Provider/Lazy indirection based dependency cycles. 26 * 27 * @since 2.0.1 28 */ 29 public final class DelegateFactory<T> implements Factory<T> { 30 31 private @Nullable Provider<T> delegate; 32 33 @Override get()34 public T get() { 35 if (delegate == null) { 36 throw new IllegalStateException(); 37 } 38 return delegate.get(); 39 } 40 41 // TODO(ronshapiro): remove this once we can reasonably expect generated code is no longer using 42 // this method 43 @Deprecated setDelegatedProvider(Provider<T> delegate)44 public void setDelegatedProvider(Provider<T> delegate) { 45 setDelegate(this, delegate); 46 } 47 48 /** 49 * Legacy javax version of the method to support libraries compiled with an older version of 50 * Dagger. Do not use directly. 51 */ 52 @Deprecated setDelegatedProvider(javax.inject.Provider<T> delegate)53 public void setDelegatedProvider(javax.inject.Provider<T> delegate) { 54 setDelegatedProvider(asDaggerProvider(delegate)); 55 } 56 57 /** 58 * Sets {@code delegateFactory}'s delegate provider to {@code delegate}. 59 * 60 * <p>{@code delegateFactory} must be an instance of {@link DelegateFactory}, otherwise this 61 * method will throw a {@link ClassCastException}. 62 */ setDelegate(Provider<T> delegateFactory, Provider<T> delegate)63 public static <T> void setDelegate(Provider<T> delegateFactory, Provider<T> delegate) { 64 DelegateFactory<T> asDelegateFactory = (DelegateFactory<T>) delegateFactory; 65 setDelegateInternal(asDelegateFactory, delegate); 66 } 67 68 /** 69 * Legacy javax version of the method to support libraries compiled with an older version of 70 * Dagger. Do not use directly. 71 */ 72 @Deprecated setDelegate( javax.inject.Provider<T> delegateFactory, javax.inject.Provider<T> delegate)73 public static <T> void setDelegate( 74 javax.inject.Provider<T> delegateFactory, javax.inject.Provider<T> delegate) { 75 DelegateFactory<T> asDelegateFactory = (DelegateFactory<T>) delegateFactory; 76 setDelegateInternal(asDelegateFactory, asDaggerProvider(delegate)); 77 } 78 setDelegateInternal( DelegateFactory<T> delegateFactory, Provider<T> delegate)79 private static <T> void setDelegateInternal( 80 DelegateFactory<T> delegateFactory, Provider<T> delegate) { 81 checkNotNull(delegate); 82 if (delegateFactory.delegate != null) { 83 throw new IllegalStateException(); 84 } 85 delegateFactory.delegate = delegate; 86 } 87 88 /** 89 * Returns the factory's delegate. 90 * 91 * @throws NullPointerException if the delegate has not been set 92 */ getDelegate()93 Provider<T> getDelegate() { 94 return checkNotNull(delegate); 95 } 96 } 97