1 /* 2 * Copyright (c) 2012, 2013, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. Oracle designates this 8 * particular file as subject to the "Classpath" exception as provided 9 * by Oracle in the LICENSE file that accompanied this code. 10 * 11 * This code is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 * version 2 for more details (a copy is included in the LICENSE file that 15 * accompanied this code). 16 * 17 * You should have received a copy of the GNU General Public License version 18 * 2 along with this work; if not, write to the Free Software Foundation, 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20 * 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 */ 25 package java.util.stream; 26 27 /** 28 * An enum describing the known shape specializations for stream abstractions. 29 * Each will correspond to a specific subinterface of {@link BaseStream} 30 * (e.g., {@code REFERENCE} corresponds to {@code Stream}, {@code INT_VALUE} 31 * corresponds to {@code IntStream}). Each may also correspond to 32 * specializations of value-handling abstractions such as {@code Spliterator}, 33 * {@code Consumer}, etc. 34 * 35 * @apiNote 36 * This enum is used by implementations to determine compatibility between 37 * streams and operations (i.e., if the output shape of a stream is compatible 38 * with the input shape of the next operation). 39 * 40 * <p>Some APIs require you to specify both a generic type and a stream shape 41 * for input or output elements, such as {@link TerminalOp} which has both 42 * generic type parameters for its input types, and a getter for the 43 * input shape. When representing primitive streams in this way, the 44 * generic type parameter should correspond to the wrapper type for that 45 * primitive type. 46 * 47 * @since 1.8 48 * @hide Visible for CTS testing only (OpenJDK8 tests). 49 */ 50 public enum StreamShape { 51 /** 52 * The shape specialization corresponding to {@code Stream} and elements 53 * that are object references. 54 */ 55 REFERENCE, 56 /** 57 * The shape specialization corresponding to {@code IntStream} and elements 58 * that are {@code int} values. 59 */ 60 INT_VALUE, 61 /** 62 * The shape specialization corresponding to {@code LongStream} and elements 63 * that are {@code long} values. 64 */ 65 LONG_VALUE, 66 /** 67 * The shape specialization corresponding to {@code DoubleStream} and 68 * elements that are {@code double} values. 69 */ 70 DOUBLE_VALUE 71 } 72