1 /* 2 * Copyright (C) 2010 The Android Open Source Project 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 package com.android.quicksearchbox.util; 17 18 /** 19 * Interface for an object that may be constructed asynchronously. In cases when the object is ready 20 * (on constructible) immediately, it provides synchronous access to it. Otherwise, the object can 21 * be sent to a {@link Consumer} later. 22 */ 23 public interface NowOrLater<C> { 24 25 /** 26 * Indicates if the object is ready (or constructible synchronously). 27 */ haveNow()28 boolean haveNow(); 29 30 /** 31 * Gets the object now. Should only be called if {@link #haveNow()} returns {@code true}, 32 * otherwise an {@link IllegalStateException} will be thrown. 33 */ getNow()34 C getNow(); 35 36 /** 37 * Request the object asynchronously. This can be called even if the object is ready now, in 38 * which case the callback may be made in context. The thread on which the consumer is called 39 * back depends on the implementation. 40 */ getLater(Consumer<? super C> consumer)41 void getLater(Consumer<? super C> consumer); 42 43 } 44