1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
|
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/* $Id$ */
package org.apache.fop.layoutmgr;
import org.apache.fop.traits.MinOptMax;
/**
* An instance of this class represents a piece of content with adjustable
* width: for example a space between words of justified text.
*
* A KnuthGlue is a feasible breaking point only if it immediately follows
* a KnuthBox.
*
* The represented piece of content is suppressed if either the KnuthGlue
* is a chosen breaking point or there isn't any KnuthBox between the
* previous breaking point and the KnuthGlue itself.
*
* So, an unsuppressible piece of content with adjustable width, for example
* a leader or a word with adjustable letter space, cannot be represented
* by a single KnuthGlue; it can be represented using the sequence:
* KnuthBox(width = 0)
* KnuthPenalty(width = 0, penalty = infinity)
* KnuthGlue(...)
* KnuthBox(width = 0)
* where the infinity penalty avoids choosing the KnuthGlue as a breaking point
* and the 0-width KnuthBoxes prevent suppression.
*
* Besides the inherited methods and attributes, this class has two attributes
* used to store the stretchability (difference between max and opt width) and
* the shrinkability (difference between opt and min width), and the methods
* to get these values.
*/
public class KnuthGlue extends KnuthElement {
private final int stretch;
private final int shrink;
private final Adjustment adjustmentClass;
/**
* Creates a new <code>KnuthGlue</code>.
*
* @param minOptMax a <code>MinOptMax</code> where the {@link MinOptMax#getOpt() opt-value} is
* mapped to the width, the {@link MinOptMax#getStretch()
* stretchability} is mapped to the stretchability and the the {@link
* MinOptMax#getShrink() shrinkability} is mapped to the shrinkability
* @param pos the Position stored in this glue
* @param auxiliary is this glue auxiliary?
*/
public KnuthGlue(MinOptMax minOptMax, Position pos, boolean auxiliary) {
super(minOptMax.getOpt(), pos, auxiliary);
this.stretch = minOptMax.getStretch();
this.shrink = minOptMax.getShrink();
this.adjustmentClass = Adjustment.NO_ADJUSTMENT;
}
/**
* Creates a new <code>KnuthGlue</code>.
*
* @param width the width of this glue
* @param stretch the stretchability of this glue
* @param shrink the shrinkability of this glue
* @param pos the Position stored in this glue
* @param auxiliary is this glue auxiliary?
*/
public KnuthGlue(int width, int stretch, int shrink, Position pos,
boolean auxiliary) {
super(width, pos, auxiliary);
this.stretch = stretch;
this.shrink = shrink;
this.adjustmentClass = Adjustment.NO_ADJUSTMENT;
}
/**
* Creates a new <code>KnuthGlue</code>.
*
* @param width the width of this glue
* @param stretch the stretchability of this glue
* @param shrink the shrinkability of this glue
* @param adjustmentClass the adjsutment class
* @param pos the Position stored in this glue
* @param auxiliary is this glue auxiliary?
*/
public KnuthGlue(int width, int stretch, int shrink, Adjustment adjustmentClass,
Position pos, boolean auxiliary) {
super(width, pos, auxiliary);
this.stretch = stretch;
this.shrink = shrink;
this.adjustmentClass = adjustmentClass;
}
/** {@inheritDoc} */
public boolean isGlue() {
return true;
}
/** @return the stretchability of this glue. */
public int getStretch() {
return stretch;
}
/** @return the shrinkability of this glue. */
public int getShrink() {
return shrink;
}
/** @return the adjustment class (or role) of this glue. */
public Adjustment getAdjustmentClass() {
return adjustmentClass;
}
/** {@inheritDoc} */
public String toString() {
StringBuffer buffer = new StringBuffer(64);
if (isAuxiliary()) {
buffer.append("aux. ");
}
buffer.append("glue");
buffer.append(" w=").append(getWidth());
buffer.append(" stretch=").append(getStretch());
buffer.append(" shrink=").append(getShrink());
if (!getAdjustmentClass().equals(Adjustment.NO_ADJUSTMENT)) {
buffer.append(" adj-class=").append(getAdjustmentClass());
}
return buffer.toString();
}
}
|
