LambdaExpressionTree.java revision 4150:fff0714129d8 
1/*
2 * Copyright (c) 2011, 2017, 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
26package com.sun.source.tree;
27
28import java.util.List;
29
30/**
31 * A tree node for a lambda expression.
32 *
33 * For example:
34 * <pre>{@code
35 *   ()->{}
36 *   (List<String> ls)->ls.size()
37 *   (x,y)-> { return x + y; }
38 * }</pre>
39 */
40public interface LambdaExpressionTree extends ExpressionTree {
41
42    /**
43     * Lambda expressions come in two forms:
44     * <ul>
45     * <li> expression lambdas, whose body is an expression, and
46     * <li> statement lambdas, whose body is a block
47     * </ul>
48     */
49    public enum BodyKind {
50        /** enum constant for expression lambdas */
51        EXPRESSION,
52        /** enum constant for statement lambdas */
53        STATEMENT
54    }
55
56    /**
57     * Returns the parameters of this lambda expression.
58     * @return the parameters
59     */
60    List<? extends VariableTree> getParameters();
61
62    /**
63     * Returns the body of the lambda expression.
64     * @return the body
65     */
66    Tree getBody();
67
68    /**
69     * Returns the kind of the body of the lambda expression.
70     * @return the kind of the body
71     */
72    BodyKind getBodyKind();
73}
74