1/*
2 * Copyright (c) 2008, 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 */
25package com.sun.beans.decoder;
26
27/**
28 * This class is intended to handle <string> element.
29 * This element specifies {@link String} values.
30 * The result value is created from text of the body of this element.
31 * For example:<pre>
32 * &lt;string&gt;description&lt;/string&gt;</pre>
33 * is equivalent to {@code "description"} in Java code.
34 * The value of inner element is calculated
35 * before adding to the string using {@link String#valueOf(Object)}.
36 * Note that all characters are used including whitespaces (' ', '\t', '\n', '\r').
37 * So the value of the element<pre>
38 * &lt;string&gt&lt;true&gt&lt;/string&gt;</pre>
39 * is not equal to the value of the element<pre>
40 * &lt;string&gt;
41 *     &lt;true&gt;
42 * &lt;/string&gt;</pre>
43 * <p>The following attribute is supported:
44 * <dl>
45 * <dt>id
46 * <dd>the identifier of the variable that is intended to store the result
47 * </dl>
48 *
49 * @since 1.7
50 *
51 * @author Sergey A. Malenkov
52 */
53public class StringElementHandler extends ElementHandler {
54    private StringBuilder sb = new StringBuilder();
55    private ValueObject value = ValueObjectImpl.NULL;
56
57    /**
58     * Adds the character that contained in this element.
59     *
60     * @param ch  the character
61     */
62    @Override
63    public final void addCharacter(char ch) {
64        if (this.sb == null) {
65            throw new IllegalStateException("Could not add chararcter to evaluated string element");
66        }
67        this.sb.append(ch);
68    }
69
70    /**
71     * Adds the string value of the argument to the string value of this element.
72     *
73     * @param argument  the value of the element that contained in this one
74     */
75    @Override
76    protected final void addArgument(Object argument) {
77        if (this.sb == null) {
78            throw new IllegalStateException("Could not add argument to evaluated string element");
79        }
80        this.sb.append(argument);
81    }
82
83    /**
84     * Returns the value of this element.
85     *
86     * @return the value of this element
87     */
88    @Override
89    protected final ValueObject getValueObject() {
90        if (this.sb != null) {
91            try {
92                this.value = ValueObjectImpl.create(getValue(this.sb.toString()));
93            }
94            catch (RuntimeException exception) {
95                getOwner().handleException(exception);
96            }
97            finally {
98                this.sb = null;
99            }
100        }
101        return this.value;
102    }
103
104    /**
105     * Returns the text of the body of this element.
106     * This method evaluates value from text of the body,
107     * and should be overridden in those handlers
108     * that extend behavior of this element.
109     *
110     * @param argument  the text of the body
111     * @return evaluated value
112     */
113    protected Object getValue(String argument) {
114        return argument;
115    }
116}
117