1 /*
2 * Copyright (c) 1997, 2015, 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 package javax.swing.text;
26
27 import java.io.Serializable;
28
29 /**
30 * This class encapsulates a single tab stop (basically as tab stops
31 * are thought of by RTF). A tab stop is at a specified distance from the
32 * left margin, aligns text in a specified way, and has a specified leader.
33 * TabStops are immutable, and usually contained in TabSets.
34 * <p>
35 * <strong>Warning:</strong>
36 * Serialized objects of this class will not be compatible with
37 * future Swing releases. The current serialization support is
38 * appropriate for short term storage or RMI between applications running
39 * the same version of Swing. As of 1.4, support for long term storage
40 * of all JavaBeans™
41 * has been added to the <code>java.beans</code> package.
42 * Please see {@link java.beans.XMLEncoder}.
43 *
44 */
45 @SuppressWarnings("serial") // Same-version serialization only
46 public class TabStop implements Serializable {
47
48 /** Character following tab is positioned at location. */
49 public static final int ALIGN_LEFT = 0;
50 /** Characters following tab are positioned such that all following
51 * characters up to next tab/newline end at location. */
52 public static final int ALIGN_RIGHT = 1;
53 /** Characters following tab are positioned such that all following
54 * characters up to next tab/newline are centered around the tabs
55 * location. */
56 public static final int ALIGN_CENTER = 2;
57 /** Characters following tab are aligned such that next
58 * decimal/tab/newline is at the tab location, very similar to
59 * RIGHT_TAB, just includes decimal as additional character to look for.
60 */
61 public static final int ALIGN_DECIMAL = 4;
62 /** Align bar */
63 public static final int ALIGN_BAR = 5;
64
65 /* Bar tabs (whatever they are) are actually a separate kind of tab
66 in the RTF spec. However, being a bar tab and having alignment
67 properties are mutually exclusive, so the reader treats barness
68 as being a kind of alignment. */
69
70 /** Lead none */
71 public static final int LEAD_NONE = 0;
72 /** Lead dots */
73 public static final int LEAD_DOTS = 1;
74 /** Lead hyphens */
75 public static final int LEAD_HYPHENS = 2;
76 /** Lead underline */
77 public static final int LEAD_UNDERLINE = 3;
78 /** Lead thickline */
79 public static final int LEAD_THICKLINE = 4;
80 /** Lead equals */
81 public static final int LEAD_EQUALS = 5;
82
83 /** Tab type. */
84 private int alignment;
85 /** Location, from the left margin, that tab is at. */
86 private float position;
87 private int leader;
88
89 /**
90 * Creates a tab at position <code>pos</code> with a default alignment
91 * and default leader.
92 * @param pos position of the tab
93 */
94 public TabStop(float pos) {
95 this(pos, ALIGN_LEFT, LEAD_NONE);
96 }
97
98 /**
99 * Creates a tab with the specified position <code>pos</code>,
100 * alignment <code>align</code> and leader <code>leader</code>.
101 * @param pos position of the tab
102 * @param align alignment of the tab
103 * @param leader leader of the tab
104 */
105 public TabStop(float pos, int align, int leader) {
106 alignment = align;
107 this.leader = leader;
108 position = pos;
109 }
110
111 /**
112 * Returns the position, as a float, of the tab.
113 * @return the position of the tab
114 */
115 public float getPosition() {
116 return position;
117 }
118
119 /**
120 * Returns the alignment, as an integer, of the tab.
121 * @return the alignment of the tab
122 */
123 public int getAlignment() {
124 return alignment;
125 }
126
127 /**
128 * Returns the leader of the tab.
129 * @return the leader of the tab
130 */
131 public int getLeader() {
132 return leader;
133 }
134
135 /**
136 * Returns true if the tabs are equal.
137 * @return true if the tabs are equal, otherwise false
138 */
139 public boolean equals(Object other)
140 {
141 if (other == this) {
142 return true;
143 }
144 if (other instanceof TabStop) {
145 TabStop o = (TabStop)other;
146 return ( (alignment == o.alignment) &&
147 (leader == o.leader) &&
148 (position == o.position) ); /* TODO: epsilon */
149 }
150 return false;
151 }
152
153 /**
154 * Returns the hashCode for the object. This must be defined
155 * here to ensure 100% pure.
156 *
157 * @return the hashCode for the object
158 */
159 public int hashCode() {
160 return alignment ^ leader ^ Math.round(position);
161 }
162
163 /* This is for debugging; perhaps it should be removed before release */
164 public String toString() {
165 String buf;
166 switch(alignment) {
167 default:
168 case ALIGN_LEFT:
169 buf = "";
170 break;
171 case ALIGN_RIGHT:
172 buf = "right ";
173 break;
174 case ALIGN_CENTER:
175 buf = "center ";
176 break;
177 case ALIGN_DECIMAL:
178 buf = "decimal ";
179 break;
180 case ALIGN_BAR:
181 buf = "bar ";
182 break;
183 }
184 buf = buf + "tab @" + String.valueOf(position);
185 if (leader != LEAD_NONE)
186 buf = buf + " (w/leaders)";
187 return buf;
188 }
189 }