java8.util.stream.StreamShape Maven / Gradle / Ivy
Show all versions of streamsupport Show documentation
/*
* Copyright (c) 2012, 2013, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
package java8.util.stream;
import java8.util.stream.BaseStream;
/**
* An enum describing the known shape specializations for stream abstractions.
* Each will correspond to a specific subinterface of {@link BaseStream}
* (e.g., {@code REFERENCE} corresponds to {@code Stream}, {@code INT_VALUE}
* corresponds to {@code IntStream}). Each may also correspond to
* specializations of value-handling abstractions such as {@code Spliterator},
* {@code Consumer}, etc.
*
* API Note:
* This enum is used by implementations to determine compatibility between
* streams and operations (i.e., if the output shape of a stream is compatible
* with the input shape of the next operation).
*
*
Some APIs require you to specify both a generic type and a stream shape
* for input or output elements, such as {@link TerminalOp} which has both
* generic type parameters for its input types, and a getter for the
* input shape. When representing primitive streams in this way, the
* generic type parameter should correspond to the wrapper type for that
* primitive type.
*
* @since 1.8
*/
enum StreamShape {
/**
* The shape specialization corresponding to {@code Stream} and elements
* that are object references.
*/
REFERENCE,
/**
* The shape specialization corresponding to {@code IntStream} and elements
* that are {@code int} values.
*/
INT_VALUE,
/**
* The shape specialization corresponding to {@code LongStream} and elements
* that are {@code long} values.
*/
LONG_VALUE,
/**
* The shape specialization corresponding to {@code DoubleStream} and
* elements that are {@code double} values.
*/
DOUBLE_VALUE
}