/* ===========================================================
* JFreeChart : a free chart library for the Java(tm) platform
* ===========================================================
*
* (C) Copyright 2000-2007, by Object Refinery Limited and Contributors.
*
* Project Info: http://www.jfree.org/jfreechart/index.html
*
* This library is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation; either version 2.1 of the License, or
* (at your option) any later version.
*
* This library 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 Lesser General Public
* License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
* USA.
*
* [Java is a trademark or registered trademark of Sun Microsystems, Inc.
* in the United States and other countries.]
*
* --------------------
* HexNumberFormat.java
* --------------------
* (C) Copyright 2007, by Richard West and Contributors.
*
* Original Author: Richard West, Advanced Micro Devices, Inc.;
* Contributor(s): David Gilbert (for Object Refinery Limited);
*
* Changes:
* --------
* 14-Jun-2007 : Version 1 (RW);
*
*/
package org.jfree.chart.util;
import java.text.FieldPosition;
import java.text.NumberFormat;
import java.text.ParsePosition;
/**
* A custom number formatter that formats numbers as hexadecimal strings.
* There are some limitations, so be careful using this class.
*
* @since 1.0.6
*/
public class HexNumberFormat extends NumberFormat {
/** Number of hexadecimal digits for a byte. */
public static final int BYTE = 2;
/** Number of hexadecimal digits for a word. */
public static final int WORD = 4;
/** Number of hexadecimal digits for a double word. */
public static final int DWORD = 8;
/** Number of hexadecimal digits for a quad word. */
public static final int QWORD = 16;
/** The number of digits (shorter strings will be left padded). */
private int m_numDigits = DWORD;
/**
* Creates a new instance with 8 digits.
*/
public HexNumberFormat() {
this(DWORD);
}
/**
* Creates a new instance with the specified number of digits.
* @param digits the digits.
*/
public HexNumberFormat(int digits) {
super();
this.m_numDigits = digits;
}
/**
* Returns the number of digits.
*
* @return The number of digits.
*/
public final int getNumberOfDigits() {
return this.m_numDigits;
}
/**
* Sets the number of digits.
*
* @param digits the number of digits.
*/
public void setNumberOfDigits(int digits) {
this.m_numDigits = digits;
}
/**
* Formats the specified number as a hexadecimal string. The decimal
* fraction is ignored.
*
* @param number the number to format.
* @param toAppendTo the buffer to append to (ignored here).
* @param pos the field position (ignored here).
*
* @return The string buffer.
*/
public StringBuffer format(double number, StringBuffer toAppendTo,
FieldPosition pos) {
return format((long) number, toAppendTo, pos);
}
/**
* Formats the specified number as a hexadecimal string. The decimal
* fraction is ignored.
*
* @param number the number to format.
* @param toAppendTo the buffer to append to (ignored here).
* @param pos the field position (ignored here).
*
* @return The string buffer.
*/
public StringBuffer format(long number, StringBuffer toAppendTo,
FieldPosition pos) {
String l_hex = Long.toHexString(number).toUpperCase();
int l_pad = this.m_numDigits - l_hex.length();
l_pad = (0 < l_pad) ? l_pad : 0;
StringBuffer l_extended = new StringBuffer("0x");
for (int i = 0; i < l_pad; i++) {
l_extended.append(0);
}
l_extended.append(l_hex);
return l_extended;
}
/**
* Parsing is not implemented, so this method always returns
* <code>null</code>.
*
* @param source ignored.
* @param parsePosition ignored.
*
* @return Always <code>null</code>.
*/
public Number parse (String source, ParsePosition parsePosition) {
return null; // don't bother with parsing
}
}
|