- /*
- * @(#)ResolutionSyntax.java 1.5 03/01/23
- *
- * Copyright 2003 Sun Microsystems, Inc. All rights reserved.
- * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
- */
-
-
- package javax.print.attribute;
-
- import java.io.Serializable;
-
- /**
- * Class 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
- * <CODE>DPI</CODE>} and {@link #DPCM <CODE>DPCM</CODE>} 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 <CODE>DPI</CODE>} 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 <CODE>DPCM</CODE>} 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.
- * <P>
- *
- * @author David Mendenhall
- * @author Alan Kaminsky
- */
- public abstract class ResolutionSyntax implements Serializable, Cloneable {
-
- /**
- * 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 <CODE>DPI</CODE>} or
- * {@link #DPCM <CODE>DPCM</CODE>}.
- *
- * @exception IllegalArgumentException
- * (unchecked exception) Thrown if <CODE>crossFeedResolution</CODE> <
- * 1 or <CODE>feedResolution</CODE> < 1 or <CODE>units</CODE> < 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 <CODE>DPI</CODE>} or
- * {@link #DPCM <CODE>DPCM</CODE>}.
- *
- * @return The value of <CODE>dphi</CODE> converted to the desired units.
- *
- * @exception IllegalArgumentException
- * (unchecked exception) Thrown if <CODE>units</CODE> < 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 <CODE>DPI</CODE>} or
- * {@link #DPCM <CODE>DPCM</CODE>}.
- *
- * @return A two-element array with the cross feed direction resolution
- * at index 0 and the feed direction resolution at index 1.
- *
- * @exception IllegalArgumentException
- * (unchecked exception) Thrown if <CODE>units</CODE> < 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 <CODE>DPI</CODE>} or
- * {@link #DPCM <CODE>DPCM</CODE>}.
- *
- * @return Cross feed direction resolution.
- *
- * @exception IllegalArgumentException
- * (unchecked exception) Thrown if <CODE>units</CODE> < 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 <CODE>DPI</CODE>} or {@link
- * #DPCM <CODE>DPCM</CODE>}.
- *
- * @return Feed direction resolution.
- *
- * @exception IllegalArgumentException
- * (unchecked exception) Thrown if <CODE>units</CODE> < 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</CODE>} or {@link
- * #DPCM <CODE>DPCM</CODE>}.
- * @param unitsName
- * Units name string, e.g. <CODE>"dpi"</CODE> or <CODE>"dpcm"</CODE>. If
- * null, no units name is appended to the result.
- *
- * @return String version of this resolution attribute.
- *
- * @exception IllegalArgumentException
- * (unchecked exception) Thrown if <CODE>units</CODE> < 1.
- */
- public String toString(int units, String unitsName) {
- StringBuffer result = new StringBuffer();
- 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</CODE> attribute's cross feed direction resolution.
- * <LI>
- * This attribute's feed direction resolution is less than or equal to the
- * <CODE>other</CODE> attribute's feed direction resolution.
- * </UL>
- *
- * @param other Resolution attribute to compare with.
- *
- * @return True if this resolution attribute is less than or equal to the
- * <CODE>other</CODE> resolution attribute, false otherwise.
- *
- * @exception NullPointerException
- * (unchecked exception) Thrown if <CODE>other</CODE> is 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</CODE> is not null.
- * <LI>
- * <CODE>object</CODE> is an instance of class ResolutionSyntax.
- * <LI>
- * This attribute's cross feed direction resolution is equal to
- * <CODE>object</CODE>'s cross feed direction resolution.
- * <LI>
- * This attribute's feed direction resolution is equal to
- * <CODE>object</CODE>'s feed direction resolution.
- * </OL>
- *
- * @param object Object to compare to.
- *
- * @return True if <CODE>object</CODE> is equivalent to this resolution
- * attribute, 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() {
- StringBuffer result = new StringBuffer();
- 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;
- }
-
- }