1/*
2 * Copyright (c) 2008, 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 */
25package com.sun.beans.decoder;
26
27/**
28 * This utility class provides {@code static} method
29 * to create the object that contains the result of method execution.
30 *
31 * @since 1.7
32 *
33 * @author Sergey A. Malenkov
34 */
35final class ValueObjectImpl implements ValueObject {
36    static final ValueObject NULL = new ValueObjectImpl(null);
37    static final ValueObject VOID = new ValueObjectImpl();
38
39    /**
40     * Returns the object that describes returning value.
41     *
42     * @param value  the result of method execution
43     * @return the object that describes value
44     */
45    static ValueObject create(Object value) {
46        return (value != null)
47                ? new ValueObjectImpl(value)
48                : NULL;
49    }
50
51    private Object value;
52    private boolean isVoid;
53
54    /**
55     * Creates the object that describes returning void value.
56     */
57    private ValueObjectImpl() {
58        this.isVoid = true;
59    }
60
61    /**
62     * Creates the object that describes returning non-void value.
63     *
64     * @param value  the result of method execution
65     */
66    private ValueObjectImpl(Object value) {
67        this.value = value;
68    }
69
70    /**
71     * Returns the result of method execution.
72     *
73     * @return the result of method execution
74     */
75    public Object getValue() {
76        return this.value;
77    }
78
79    /**
80     * Returns {@code void} state of this value object.
81     *
82     * @return {@code true} if value should be ignored,
83     *         {@code false} otherwise
84     */
85    public boolean isVoid() {
86        return this.isVoid;
87    }
88}
89