aboutsummaryrefslogtreecommitdiffstats
path: root/src/java/org/apache/fop/fo/properties/FixedLength.java
blob: 84d159edf9cf65969d4b1a9e5d91b18af44bb476 (plain)
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
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
/*
 * 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.fo.properties;

import org.apache.fop.datatypes.PercentBaseContext;

/**
 * An absolute length quantity in XSL
 */
public final class FixedLength extends LengthProperty {

    /** Describes the unit pica. */
    public static final String PICA = "pc";

    /** Describes the unit point. */
    public static final String POINT = "pt";

    /** Describes the unit millimeter. */
    public static final String MM = "mm";

    /** Describes the unit centimeter. */
    public static final String CM = "cm";

    /** Describes the unit inch. */
    public static final String INCH = "in";

    /** Describes the unit millipoint. */
    public static final String MPT = "mpt";

    /** cache holding all canonical FixedLength instances */
    private static final PropertyCache cache = new PropertyCache(FixedLength.class);

    /** canonical zero-length instance */
    public static final FixedLength ZERO_FIXED_LENGTH = new FixedLength(0, FixedLength.MPT, 1.0f);

    private int millipoints;

    /**
     * Set the length given a number of units, a unit name and
     * an assumed resolution (used in case the units are pixels)
     *
     * @param numUnits  quantity of input units
     * @param units     input unit specifier
     * @param res       input/source resolution
     */
    private FixedLength(double numUnits, String units, float res) {
        this.millipoints = convert(numUnits, units, res);
    }

    /**
     * Return the cached {@link FixedLength} instance corresponding
     * to the computed value in base-units (millipoints).
     *
     * @param numUnits  quantity of input units
     * @param units     input unit specifier
     * @param sourceResolution input/source resolution (= ratio of pixels per pt)
     * @return  the canonical FixedLength instance corresponding
     *          to the given number of units and unit specifier
     *          in the given resolution
     */
    public static FixedLength getInstance(double numUnits,
                                          String units,
                                          float sourceResolution) {
        if (numUnits == 0.0) {
            return ZERO_FIXED_LENGTH;
        } else {
            return (FixedLength)cache.fetch(
                new FixedLength(numUnits, units, sourceResolution));
        }

    }

    /**
     * Return the cached {@link FixedLength} instance corresponding
     * to the computed value
     * This method assumes a source-resolution of 1 (1px = 1pt)
     *
     * @param numUnits  input units
     * @param units     unit specifier
     * @return  the canonical FixedLength instance corresponding
     *          to the given number of units and unit specifier
     */
    public static FixedLength getInstance(double numUnits,
                                          String units) {
        return getInstance(numUnits, units, 1.0f);

    }

    /**
     * Return the cached {@link FixedLength} instance corresponding
     * to the computed value.
     * This method assumes 'millipoints' (non-standard) as units,
     * and an implied source-resolution of 1 (1px = 1pt).
     *
     * @param numUnits  input units
     * @return  the canonical FixedLength instance corresponding
     *          to the given number of units and unit specifier
     */
    public static FixedLength getInstance(double numUnits) {
        return getInstance(numUnits, FixedLength.MPT, 1.0f);

    }

    /**
     * Convert the given length to a dimensionless integer representing
     * a whole number of base units (milli-points).
     *
     * @param dvalue quantity of input units
     * @param unit input unit specifier (in, cm, etc.)
     * @param res   the input/source resolution (in case the unit spec is "px")
     */
    private static int convert(double dvalue, String unit, float res) {
        // TODO: Maybe this method has a better place in org.apache.fop.util.UnitConv?.

        if ("px".equals(unit)) {
            //device-dependent units, take the resolution into account
            dvalue *= (res * 1000);
        } else {
            if (FixedLength.INCH.equals(unit)) {
                dvalue *= 72000;
            } else if (FixedLength.CM.equals(unit)) {
                dvalue *= 28346.4567;
            } else if (FixedLength.MM.equals(unit)) {
                dvalue *= 2834.64567;
            } else if (FixedLength.POINT.equals(unit)) {
                dvalue *= 1000;
            } else if (FixedLength.PICA.equals(unit)) {
                dvalue *= 12000;
            } else if (!FixedLength.MPT.equals(unit)) {
                dvalue = 0;
                log.error("Unknown length unit '" + unit + "'");
            }
        }
        return (int)dvalue;
    }

    /** {@inheritDoc} */
    public int getValue() {
        return millipoints;
    }

    /** {@inheritDoc} */
    public int getValue(PercentBaseContext context) {
        return millipoints;
    }

    /** {@inheritDoc} */
    public double getNumericValue() {
        return millipoints;
    }

    /** {@inheritDoc} */
    public double getNumericValue(PercentBaseContext context) {
        return millipoints;
    }

    /**
     * Return true since a FixedLength is always absolute.
     * {@inheritDoc}
     */
    public boolean isAbsolute() {
        return true;
    }

    /** {@inheritDoc} */
    public String toString() {
        return millipoints + FixedLength.MPT;
    }

    /** {@inheritDoc} */
    public boolean equals(Object obj) {
        if (this == obj) {
            return true;
        }
        if (obj instanceof FixedLength) {
            return (((FixedLength)obj).millipoints == this.millipoints);
        }
        return false;
    }

    /** {@inheritDoc} */
    public int hashCode() {
        return millipoints;
    }
}