| /* |
| * Copyright (c) 2000, 2017, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. Oracle designates this |
| * particular file as subject to the "Classpath" exception as provided |
| * by Oracle in the LICENSE file that accompanied this code. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| package javax.print.attribute; |
| |
| import java.io.Serializable; |
| |
| /** |
| * Class {@code ResolutionSyntax} is an abstract base class providing the common |
| * implementation of all attributes denoting a printer resolution. |
| * <p> |
| * A resolution attribute's value consists of two items, the cross feed |
| * direction resolution and the feed direction resolution. A resolution |
| * attribute may be constructed by supplying the two values and indicating the |
| * units in which the values are measured. Methods are provided to return a |
| * resolution attribute's values, indicating the units in which the values are |
| * to be returned. The two most common resolution units are dots per inch (dpi) |
| * and dots per centimeter (dpcm), and exported constants {@link #DPI DPI} and |
| * {@link #DPCM DPCM} are provided for indicating those units. |
| * <p> |
| * Once constructed, a resolution attribute's value is immutable. |
| * <p> |
| * <b>Design</b> |
| * <p> |
| * A resolution attribute's cross feed direction resolution and feed direction |
| * resolution values are stored internally using units of dots per 100 inches |
| * (dphi). Storing the values in dphi rather than, say, metric units allows |
| * precise integer arithmetic conversions between dpi and dphi and between dpcm |
| * and dphi: 1 dpi = 100 dphi, 1 dpcm = 254 dphi. Thus, the values can be stored |
| * into and retrieved back from a resolution attribute in either units with no |
| * loss of precision. This would not be guaranteed if a floating point |
| * representation were used. However, roundoff error will in general occur if a |
| * resolution attribute's values are created in one units and retrieved in |
| * different units; for example, 600 dpi will be rounded to 236 dpcm, whereas |
| * the true value (to five figures) is 236.22 dpcm. |
| * <p> |
| * Storing the values internally in common units of dphi lets two resolution |
| * attributes be compared without regard to the units in which they were |
| * created; for example, 300 dpcm will compare equal to 762 dpi, as they both |
| * are stored as 76200 dphi. In particular, a lookup service can match |
| * resolution attributes based on equality of their serialized representations |
| * regardless of the units in which they were created. Again, using integers for |
| * internal storage allows precise equality comparisons to be done, which would |
| * not be guaranteed if a floating point representation were used. |
| * <p> |
| * The exported constant {@link #DPI DPI} is actually the conversion factor by |
| * which to multiply a value in dpi to get the value in dphi. Likewise, the |
| * exported constant {@link #DPCM DPCM} is the conversion factor by which to |
| * multiply a value in dpcm to get the value in dphi. A client can specify a |
| * resolution value in units other than dpi or dpcm by supplying its own |
| * conversion factor. However, since the internal units of dphi was chosen with |
| * supporting only the external units of dpi and dpcm in mind, there is no |
| * guarantee that the conversion factor for the client's units will be an exact |
| * integer. If the conversion factor isn't an exact integer, resolution values |
| * in the client's units won't be stored precisely. |
| * |
| * @author David Mendenhall |
| * @author Alan Kaminsky |
| */ |
| public abstract class ResolutionSyntax implements Serializable, Cloneable { |
| |
| /** |
| * Use serialVersionUID from JDK 1.4 for interoperability. |
| */ |
| private static final long serialVersionUID = 2706743076526672017L; |
| |
| /** |
| * Cross feed direction resolution in units of dots per 100 inches (dphi). |
| * |
| * @serial |
| */ |
| private int crossFeedResolution; |
| |
| /** |
| * Feed direction resolution in units of dots per 100 inches (dphi). |
| * |
| * @serial |
| */ |
| private int feedResolution; |
| |
| /** |
| * Value to indicate units of dots per inch (dpi). It is actually the |
| * conversion factor by which to multiply dpi to yield dphi (100). |
| */ |
| public static final int DPI = 100; |
| |
| /** |
| * Value to indicate units of dots per centimeter (dpcm). It is actually the |
| * conversion factor by which to multiply dpcm to yield dphi (254). |
| */ |
| public static final int DPCM = 254; |
| |
| /** |
| * Construct a new resolution attribute from the given items. |
| * |
| * @param crossFeedResolution cross feed direction resolution |
| * @param feedResolution feed direction resolution |
| * @param units unit conversion factor, e.g. {@link #DPI DPI} or |
| * {@link #DPCM DPCM} |
| * @throws IllegalArgumentException if {@code crossFeedResolution < 1} or |
| * {@code feedResolution < 1} or {@code units < 1} |
| */ |
| public ResolutionSyntax(int crossFeedResolution, int feedResolution, |
| int units) { |
| |
| if (crossFeedResolution < 1) { |
| throw new IllegalArgumentException("crossFeedResolution is < 1"); |
| } |
| if (feedResolution < 1) { |
| throw new IllegalArgumentException("feedResolution is < 1"); |
| } |
| if (units < 1) { |
| throw new IllegalArgumentException("units is < 1"); |
| } |
| |
| this.crossFeedResolution = crossFeedResolution * units; |
| this.feedResolution = feedResolution * units; |
| } |
| |
| /** |
| * Convert a value from dphi to some other units. The result is rounded to |
| * the nearest integer. |
| * |
| * @param dphi value (dphi) to convert |
| * @param units unit conversion factor, e.g. {@link #DPI DPI} or |
| * {@link #DPCM DPCM} |
| * @return the value of {@code dphi} converted to the desired units |
| * @throws IllegalArgumentException if {@code units < 1} |
| */ |
| private static int convertFromDphi(int dphi, int units) { |
| if (units < 1) { |
| throw new IllegalArgumentException(": units is < 1"); |
| } |
| int round = units / 2; |
| return (dphi + round) / units; |
| } |
| |
| /** |
| * Get this resolution attribute's resolution values in the given units. The |
| * values are rounded to the nearest integer. |
| * |
| * @param units unit conversion factor, e.g. {@link #DPI DPI} or |
| * {@link #DPCM DPCM} |
| * @return a two-element array with the cross feed direction resolution at |
| * index 0 and the feed direction resolution at index 1 |
| * @throws IllegalArgumentException if {@code units < 1} |
| */ |
| public int[] getResolution(int units) { |
| return new int[] { getCrossFeedResolution(units), |
| getFeedResolution(units) |
| }; |
| } |
| |
| /** |
| * Returns this resolution attribute's cross feed direction resolution in |
| * the given units. The value is rounded to the nearest integer. |
| * |
| * @param units unit conversion factor, e.g. {@link #DPI DPI} or |
| * {@link #DPCM DPCM} |
| * @return cross feed direction resolution |
| * @throws IllegalArgumentException if {@code units < 1} |
| */ |
| public int getCrossFeedResolution(int units) { |
| return convertFromDphi (crossFeedResolution, units); |
| } |
| |
| /** |
| * Returns this resolution attribute's feed direction resolution in the |
| * given units. The value is rounded to the nearest integer. |
| * |
| * @param units unit conversion factor, e.g. {@link #DPI DPI} or |
| * {@link #DPCM DPCM} |
| * @return feed direction resolution |
| * @throws IllegalArgumentException if {@code units < 1} |
| */ |
| public int getFeedResolution(int units) { |
| return convertFromDphi (feedResolution, units); |
| } |
| |
| /** |
| * Returns a string version of this resolution attribute in the given units. |
| * The string takes the form <code>"<i>C</i>x<i>F</i> <i>U</i>"</code>, |
| * where <i>C</i> is the cross feed direction resolution, <i>F</i> is the |
| * feed direction resolution, and <i>U</i> is the units name. The values are |
| * rounded to the nearest integer. |
| * |
| * @param units unit conversion factor, e.g. {@link #DPI CODE>DPI} or |
| * {@link #DPCM DPCM} |
| * @param unitsName units name string, e.g. {@code "dpi"} or |
| * {@code "dpcm"}. If {@code null}, no units name is appended to the |
| * result. |
| * @return string version of this resolution attribute |
| * @throws IllegalArgumentException if {@code units < 1} |
| */ |
| public String toString(int units, String unitsName) { |
| StringBuilder result = new StringBuilder(); |
| result.append(getCrossFeedResolution (units)); |
| result.append('x'); |
| result.append(getFeedResolution (units)); |
| if (unitsName != null) { |
| result.append (' '); |
| result.append (unitsName); |
| } |
| return result.toString(); |
| } |
| |
| /** |
| * Determine whether this resolution attribute's value is less than or equal |
| * to the given resolution attribute's value. This is true if all of the |
| * following conditions are true: |
| * <ul> |
| * <li>This attribute's cross feed direction resolution is less than or |
| * equal to the {@code other} attribute's cross feed direction resolution. |
| * <li>This attribute's feed direction resolution is less than or equal to |
| * the {@code other} attribute's feed direction resolution. |
| * </ul> |
| * |
| * @param other resolution attribute to compare with |
| * @return {@code true} if this resolution attribute is less than or equal |
| * to the {@code other} resolution attribute, {@code false} |
| * otherwise |
| * @throws NullPointerException if {@code other} is {@code null} |
| */ |
| public boolean lessThanOrEquals(ResolutionSyntax other) { |
| return (this.crossFeedResolution <= other.crossFeedResolution && |
| this.feedResolution <= other.feedResolution); |
| } |
| |
| /** |
| * Returns whether this resolution attribute is equivalent to the passed in |
| * object. To be equivalent, all of the following conditions must be true: |
| * <ol type=1> |
| * <li>{@code object} is not {@code null}. |
| * <li>{@code object} is an instance of class {@code ResolutionSyntax}. |
| * <li>This attribute's cross feed direction resolution is equal to |
| * {@code object}'s cross feed direction resolution. |
| * <li>This attribute's feed direction resolution is equal to |
| * {@code object}'s feed direction resolution. |
| * </ol> |
| * |
| * @param object {@code Object} to compare to |
| * @return {@code true} if {@code object} is equivalent to this resolution |
| * attribute, {@code false} otherwise |
| */ |
| public boolean equals(Object object) { |
| |
| return(object != null && |
| object instanceof ResolutionSyntax && |
| this.crossFeedResolution == |
| ((ResolutionSyntax) object).crossFeedResolution && |
| this.feedResolution == |
| ((ResolutionSyntax) object).feedResolution); |
| } |
| |
| /** |
| * Returns a hash code value for this resolution attribute. |
| */ |
| public int hashCode() { |
| return(((crossFeedResolution & 0x0000FFFF)) | |
| ((feedResolution & 0x0000FFFF) << 16)); |
| } |
| |
| /** |
| * Returns a string version of this resolution attribute. The string takes |
| * the form <code>"<i>C</i>x<i>F</i> dphi"</code>, where <i>C</i> is the |
| * cross feed direction resolution and <i>F</i> is the feed direction |
| * resolution. The values are reported in the internal units of dphi. |
| */ |
| public String toString() { |
| StringBuilder result = new StringBuilder(); |
| result.append(crossFeedResolution); |
| result.append('x'); |
| result.append(feedResolution); |
| result.append(" dphi"); |
| return result.toString(); |
| } |
| |
| /** |
| * Returns this resolution attribute's cross feed direction resolution in |
| * units of dphi. (For use in a subclass.) |
| * |
| * @return cross feed direction resolution |
| */ |
| protected int getCrossFeedResolutionDphi() { |
| return crossFeedResolution; |
| } |
| |
| /** |
| * Returns this resolution attribute's feed direction resolution in units of |
| * dphi. (For use in a subclass.) |
| * |
| * @return feed direction resolution |
| */ |
| protected int getFeedResolutionDphi() { |
| return feedResolution; |
| } |
| } |
