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.base.io; |
17 | |
18 | |
19 | /** |
20 | * Wraps a text output stream. |
21 | * |
22 | * @author Michael Meyling |
23 | */ |
24 | public class SubTextInput extends TextInput { |
25 | |
26 | /** Absolute start of this input relative to base {@link SubTextInput}. */ |
27 | private final int absoluteStart; |
28 | |
29 | /** Absolute end of this input relative to base {@link SubTextInput}. */ |
30 | private final int absoluteEnd; |
31 | |
32 | /** |
33 | * Constructor. |
34 | * |
35 | * @param source Text input. |
36 | */ |
37 | public SubTextInput(final String source) { |
38 | super(source); |
39 | this.absoluteStart = 0; |
40 | this.absoluteEnd = source.length(); |
41 | } |
42 | |
43 | /** |
44 | * Constructor. |
45 | * |
46 | * @param original Parent input. |
47 | * @param absoluteStart Input part starts here. |
48 | * @param absoluteEnd Input part ends here. |
49 | */ |
50 | public SubTextInput(final SubTextInput original, final int absoluteStart, final int absoluteEnd) { |
51 | super(original.getAbsoluteSubstring(absoluteStart, absoluteEnd)); |
52 | this.absoluteStart = absoluteStart; |
53 | this.absoluteEnd = absoluteEnd; |
54 | } |
55 | |
56 | /** |
57 | * Get the absolute start position of the current {@link SubTextInput}. |
58 | * |
59 | * @return Absolute start position. |
60 | */ |
61 | public int getAbsoluteStart() { |
62 | return absoluteStart; |
63 | } |
64 | |
65 | /** |
66 | * Get the absolute end position of the current {@link SubTextInput}. |
67 | * |
68 | * @return Absolute end position. |
69 | */ |
70 | public int getAbsoluteEnd() { |
71 | return absoluteEnd; |
72 | } |
73 | |
74 | /** |
75 | * Get the absolute position of the current position. |
76 | * |
77 | * @return Absolute position of current position. |
78 | */ |
79 | public int getAbsolutePosition() { |
80 | return getAbsoluteStart() + getPosition(); |
81 | } |
82 | |
83 | /** |
84 | * Set the current position by calculating the relative position |
85 | * from the given absolute position. |
86 | * |
87 | * @param absolutePosition This should be the absolute position. |
88 | */ |
89 | public void setAbsolutePosition(final int absolutePosition) { |
90 | setPosition(absolutePosition - getAbsoluteStart()); |
91 | } |
92 | |
93 | /** |
94 | * Get sub string of source. The given parameters have values for the underlying original |
95 | * SubTextInput at the base. |
96 | * |
97 | * @param absoluteFrom Absolute start of sub string. |
98 | * @param absoluteTo Absolute end of sub string. |
99 | * @return Sub string. |
100 | */ |
101 | public String getAbsoluteSubstring(final int absoluteFrom, final int absoluteTo) { |
102 | return getSubstring(absoluteFrom - getAbsoluteStart(), absoluteTo - getAbsoluteStart()); |
103 | } |
104 | |
105 | /** |
106 | * Get sub string of source as a new {@link SubTextInput}. The given parameters have |
107 | * values for the underlying original SubTextInput at the base. |
108 | * |
109 | * @param absoluteFrom Absolute start of sub string. |
110 | * @param absoluteTo Absolute end of sub string. |
111 | * @return Sub string. |
112 | */ |
113 | public SubTextInput getSubTextInput(final int absoluteFrom, final int absoluteTo) { |
114 | return new SubTextInput(this, absoluteFrom, absoluteTo); |
115 | } |
116 | |
117 | } |