1 | /* This file is part of the project "Hilbert II" - http://www.qedeq.org |
2 | * |
3 | * Copyright 2000-2014, Michael Meyling <mime@qedeq.org>. |
4 | * |
5 | * "Hilbert II" is free software; you can redistribute |
6 | * it and/or modify it under the terms of the GNU General Public |
7 | * License as published by the Free Software Foundation; either |
8 | * version 2 of the License, or (at your option) any later version. |
9 | * |
10 | * This program is distributed in the hope that it will be useful, |
11 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
12 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
13 | * GNU General Public License for more details. |
14 | */ |
15 | |
16 | package org.qedeq.kernel.xml.handler.list; |
17 | |
18 | import java.util.ArrayList; |
19 | import java.util.List; |
20 | |
21 | import org.qedeq.kernel.se.base.list.Element; |
22 | import org.qedeq.kernel.se.base.list.ElementList; |
23 | import org.qedeq.kernel.se.dto.list.DefaultAtom; |
24 | import org.qedeq.kernel.se.dto.list.DefaultElementList; |
25 | import org.qedeq.kernel.xml.handler.common.AbstractSimpleHandler; |
26 | import org.qedeq.kernel.xml.handler.common.SaxDefaultHandler; |
27 | import org.qedeq.kernel.xml.handler.common.SimpleAttributes; |
28 | |
29 | |
30 | /** |
31 | * Parse elements. For example formulas and terms are build of |
32 | * {@link org.qedeq.kernel.se.base.list.Element}s. |
33 | * <P> |
34 | * This handler knows nothing about special forms. It doesn't do any |
35 | * validating. It simply puts all attributes into string atoms and |
36 | * adds all sub elements. The element name is taken for the operator name. |
37 | * |
38 | * @author Michael Meyling |
39 | */ |
40 | public class ElementHandler extends AbstractSimpleHandler { |
41 | |
42 | /** Value object element. */ |
43 | private Element result; |
44 | |
45 | /** Element stack. */ |
46 | private final List elements; |
47 | |
48 | |
49 | /** |
50 | * Deals with elements. |
51 | * |
52 | * @param handler Parent handler. |
53 | */ |
54 | public ElementHandler(final AbstractSimpleHandler handler) { |
55 | super(handler); |
56 | elements = new ArrayList(20); |
57 | } |
58 | |
59 | /** |
60 | * Deals with elements. |
61 | * |
62 | * @param handler Parent handler. |
63 | */ |
64 | public ElementHandler(final SaxDefaultHandler handler) { |
65 | super(handler); |
66 | elements = new ArrayList(20); |
67 | } |
68 | |
69 | public final void init() { |
70 | result = null; |
71 | elements.clear(); |
72 | } |
73 | |
74 | /** |
75 | * Get parsed element. |
76 | * |
77 | * @return Parsed element. |
78 | */ |
79 | public final Element getElement() { |
80 | return result; |
81 | } |
82 | |
83 | public final void startElement(final String name, final SimpleAttributes attributes) { |
84 | final String[] values = attributes.getKeySortedStringValues(); |
85 | final ElementList element = new DefaultElementList(name); |
86 | for (int i = 0; i < values.length; i++) { |
87 | element.add(new DefaultAtom(values[i])); |
88 | } |
89 | elements.add(element); |
90 | } |
91 | |
92 | public final void endElement(final String name) { |
93 | ElementList last = (ElementList) elements.get(elements.size() - 1); |
94 | elements.remove(elements.size() - 1); |
95 | if (elements.size() > 0) { |
96 | ((ElementList) elements.get(elements.size() - 1)).add(last); |
97 | } else { |
98 | result = last; |
99 | } |
100 | } |
101 | |
102 | public final void characters(final String name, final String data) { |
103 | ElementList last = (ElementList) elements.get(elements.size() - 1); |
104 | last.add(new DefaultAtom(data)); |
105 | } |
106 | |
107 | } |