--- /dev/null
+/* Double.java -- object wrapper for double
+ Copyright (C) 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005
+ Free Software Foundation, Inc.
+
+ This file is part of GNU Classpath.
+
+ GNU Classpath is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2, or (at your option)
+ any later version.
+
+ GNU Classpath 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 for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with GNU Classpath; see the file COPYING. If not, write to the
+ Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ 02110-1301 USA.
+
+ Linking this library statically or dynamically with other modules is
+ making a combined work based on this library. Thus, the terms and
+ conditions of the GNU General Public License cover the whole
+ combination.
+
+ As a special exception, the copyright holders of this library give you
+ permission to link this library with independent modules to produce an
+ executable, regardless of the license terms of these independent
+ modules, and to copy and distribute the resulting executable under
+ terms of your choice, provided that you also meet, for each linked
+ independent module, the terms and conditions of the license of that
+ module. An independent module is a module which is not derived from
+ or based on this library. If you modify this library, you may extend
+ this exception to your version of the library, but you are not
+ obligated to do so. If you do not wish to do so, delete this
+ exception statement from your version. */
+
+//package java.lang;
+
+/**
+ * Instances of class <code>Double</code> represent primitive
+ * <code>double</code> values.
+ *
+ * Additionally, this class provides various helper functions and variables
+ * related to doubles.
+ *
+ * @author Paul Fisher
+ * @author Andrew Haley (aph@cygnus.com)
+ * @author Eric Blake (ebb9@email.byu.edu)
+ * @author Tom Tromey (tromey@redhat.com)
+ * @author Andrew John Hughes (gnu_andrew@member.fsf.org)
+ * @since 1.0
+ * @status partly updated to 1.5
+ */
+
+public final class Double extends Number // implements Comparable<Double>
+{
+ /**
+ * Compatible with JDK 1.0+.
+ */
+ /**
+ * The immutable value of this Double.
+ *
+ * @serial the wrapped double
+ */
+
+ private final double value;
+
+ /**
+ * Create a <code>Double</code> from the primitive <code>double</code>
+ * specified.
+ *
+ * @param value
+ * the <code>double</code> argument
+ */
+ public Double(double value) {
+ this.value = value;
+ }
+
+ /**
+ * Create a <code>Double</code> from the specified <code>String</code>. This
+ * method calls <code>Double.parseDouble()</code>.
+ *
+ * @param s
+ * the <code>String</code> to convert
+ * @throws NumberFormatException
+ * if <code>s</code> cannot be parsed as a <code>double</code>
+ * @throws NullPointerException
+ * if <code>s</code> is null
+ * @see #parseDouble(String)
+ */
+ public Double(String s) {
+ value = parseDouble(s);
+ }
+
+ /**
+ * Convert the <code>double</code> to a <code>String</code>. Floating-point
+ * string representation is fairly complex: here is a rundown of the possible
+ * values. "<code>[-]</code>" indicates that a negative sign will be printed
+ * if the value (or exponent) is negative. "<code><number></code>" means
+ * a string of digits ('0' to '9'). "<code><digit></code>" means a
+ * single digit ('0' to '9').<br>
+ *
+ * <table border=1>
+ * <tr>
+ * <th>Value of Double</th>
+ * <th>String Representation</th>
+ * </tr>
+ * <tr>
+ * <td>[+-] 0</td>
+ * <td><code>[-]0.0</code></td>
+ * </tr>
+ * <tr>
+ * <td>Between [+-] 10<sup>-3</sup> and 10<sup>7</sup>, exclusive</td>
+ * <td><code>[-]number.number</code></td>
+ * </tr>
+ * <tr>
+ * <td>Other numeric value</td>
+ * <td><code>[-]<digit>.<number>
+ * E[-]<number></code></td>
+ * </tr>
+ * <tr>
+ * <td>[+-] infinity</td>
+ * <td><code>[-]Infinity</code></td>
+ * </tr>
+ * <tr>
+ * <td>NaN</td>
+ * <td><code>NaN</code></td>
+ * </tr>
+ * </table>
+ *
+ * Yes, negative zero <em>is</em> a possible value. Note that there is
+ * <em>always</em> a <code>.</code> and at least one digit printed after it:
+ * even if the number is 3, it will be printed as <code>3.0</code>. After the
+ * ".", all digits will be printed except trailing zeros. The result is
+ * rounded to the shortest decimal number which will parse back to the same
+ * double.
+ *
+ * <p>
+ * To create other output formats, use {@link java.text.NumberFormat}.
+ *
+ * @XXX specify where we are not in accord with the spec.
+ *
+ * @param d
+ * the <code>double</code> to convert
+ * @return the <code>String</code> representing the <code>double</code>
+ */
+ public static String toString(double d) {
+ return String.valueOf(d);
+ }
+
+ /**
+ * Convert a double value to a hexadecimal string. This converts as follows:
+ * <ul>
+ * <li>A NaN value is converted to the string "NaN".
+ * <li>Positive infinity is converted to the string "Infinity".
+ * <li>Negative infinity is converted to the string "-Infinity".
+ * <li>For all other values, the first character of the result is '-' if the
+ * value is negative. This is followed by '0x1.' if the value is normal, and
+ * '0x0.' if the value is denormal. This is then followed by a (lower-case)
+ * hexadecimal representation of the mantissa, with leading zeros as required
+ * for denormal values. The next character is a 'p', and this is followed by a
+ * decimal representation of the unbiased exponent.
+ * </ul>
+ *
+ * @param d
+ * the double value
+ * @return the hexadecimal string representation
+ * @since 1.5
+ */
+ public static String toHexString(double d) {
+ /*
+ * if (isNaN(d)) return "NaN"; if (isInfinite(d)) return d < 0 ? "-Infinity"
+ * : "Infinity";
+ *
+ * long bits = doubleToLongBits(d); StringBuilder result = new
+ * StringBuilder();
+ *
+ * if (bits < 0) result.append('-'); result.append("0x");
+ *
+ * final int mantissaBits = 52; final int exponentBits = 11; long mantMask =
+ * (1L << mantissaBits) - 1; long mantissa = bits & mantMask; long expMask =
+ * (1L << exponentBits) - 1; long exponent = (bits >>> mantissaBits) &
+ * expMask;
+ *
+ * result.append(exponent == 0 ? '0' : '1'); result.append('.');
+ * result.append(Long.toHexString(mantissa)); if (exponent == 0 && mantissa
+ * != 0) { // Treat denormal specially by inserting '0's to make // the
+ * length come out right. The constants here are // to account for things
+ * like the '0x'. int offset = 4 + ((bits < 0) ? 1 : 0); // The silly +3 is
+ * here to keep the code the same between // the Float and Double cases. In
+ * Float the value is // not a multiple of 4. int desiredLength = offset +
+ * (mantissaBits + 3) / 4; while (result.length() < desiredLength)
+ * result.insert(offset, '0'); } result.append('p'); if (exponent == 0 &&
+ * mantissa == 0) { // Zero, so do nothing special. } else { // Apply bias.
+ * boolean denormal = exponent == 0; exponent -= (1 << (exponentBits - 1)) -
+ * 1; // Handle denormal. if (denormal) ++exponent; }
+ *
+ * result.append(Long.toString(exponent)); return result.toString();
+ */
+ return "0x0";
+ }
+
+ /**
+ * Returns a <code>Double</code> object wrapping the value. In contrast to the
+ * <code>Double</code> constructor, this method may cache some values. It is
+ * used by boxing conversion.
+ *
+ * @param val
+ * the value to wrap
+ * @return the <code>Double</code>
+ * @since 1.5
+ */
+ public static Double valueOf(double val) {
+ // We don't actually cache, but we could.
+ return new Double(val);
+ }
+
+ /**
+ * Create a new <code>Double</code> object using the <code>String</code>.
+ *
+ * @param s
+ * the <code>String</code> to convert
+ * @return the new <code>Double</code>
+ * @throws NumberFormatException
+ * if <code>s</code> cannot be parsed as a <code>double</code>
+ * @throws NullPointerException
+ * if <code>s</code> is null.
+ * @see #parseDouble(String)
+ */
+ public static Double valueOf(String s) {
+ return new Double(parseDouble(s));
+ }
+
+ /**
+ * Parse the specified <code>String</code> as a <code>double</code>. The
+ * extended BNF grammar is as follows:<br>
+ *
+ * <pre>
+ * <em>DecodableString</em>:
+ * ( [ <code>-</code> | <code>+</code> ] <code>NaN</code> )
+ * | ( [ <code>-</code> | <code>+</code> ] <code>Infinity</code> )
+ * | ( [ <code>-</code> | <code>+</code> ] <em>FloatingPoint</em>
+ * [ <code>f</code> | <code>F</code> | <code>d</code>
+ * | <code>D</code>] )
+ * <em>FloatingPoint</em>:
+ * ( { <em>Digit</em> }+ [ <code>.</code> { <em>Digit</em> } ]
+ * [ <em>Exponent</em> ] )
+ * | ( <code>.</code> { <em>Digit</em> }+ [ <em>Exponent</em> ] )
+ * <em>Exponent</em>:
+ * ( ( <code>e</code> | <code>E</code> )
+ * [ <code>-</code> | <code>+</code> ] { <em>Digit</em> }+ )
+ * <em>Digit</em>: <em><code>'0'</code> through <code>'9'</code></em>
+ * </pre>
+ *
+ * <p>
+ * NaN and infinity are special cases, to allow parsing of the output of
+ * toString. Otherwise, the result is determined by calculating
+ * <em>n * 10<sup>exponent</sup></em> to infinite precision, then rounding to
+ * the nearest double. Remember that many numbers cannot be precisely
+ * represented in floating point. In case of overflow, infinity is used, and
+ * in case of underflow, signed zero is used. Unlike Integer.parseInt, this
+ * does not accept Unicode digits outside the ASCII range.
+ *
+ * <p>
+ * If an unexpected character is found in the <code>String</code>, a
+ * <code>NumberFormatException</code> will be thrown. Leading and trailing
+ * 'whitespace' is ignored via <code>String.trim()</code>, but spaces internal
+ * to the actual number are not allowed.
+ *
+ * <p>
+ * To parse numbers according to another format, consider using
+ * {@link java.text.NumberFormat}.
+ *
+ * @XXX specify where/how we are not in accord with the spec.
+ *
+ * @param str
+ * the <code>String</code> to convert
+ * @return the <code>double</code> value of <code>s</code>
+ * @throws NumberFormatException
+ * if <code>s</code> cannot be parsed as a <code>double</code>
+ * @throws NullPointerException
+ * if <code>s</code> is null
+ * @see #MIN_VALUE
+ * @see #MAX_VALUE
+ * @see #POSITIVE_INFINITY
+ * @see #NEGATIVE_INFINITY
+ * @since 1.2
+ */
+ public static double parseDouble(String str) {
+ return nativeparsedouble(str);
+ }
+
+ public static native double nativeparsedouble(String str);
+
+ public static native double nativeparsedouble(int start, int length, byte[] str);
+
+ /**
+ * Return <code>true</code> if the <code>double</code> has the same value as
+ * <code>NaN</code>, otherwise return <code>false</code>.
+ *
+ * @param v
+ * the <code>double</code> to compare
+ * @return whether the argument is <code>NaN</code>.
+ */
+ public static boolean isNaN(double v) {
+ // This works since NaN != NaN is the only reflexive inequality
+ // comparison which returns true.
+ return v != v;
+ }
+
+ /**
+ * Return <code>true</code> if the <code>double</code> has a value equal to
+ * either <code>NEGATIVE_INFINITY</code> or <code>POSITIVE_INFINITY</code>,
+ * otherwise return <code>false</code>.
+ *
+ * @param v
+ * the <code>double</code> to compare
+ * @return whether the argument is (-/+) infinity.
+ */
+ public static boolean isInfinite(double v) {
+ return false;
+ }
+
+ /**
+ * Return <code>true</code> if the value of this <code>Double</code> is the
+ * same as <code>NaN</code>, otherwise return <code>false</code>.
+ *
+ * @return whether this <code>Double</code> is <code>NaN</code>
+ */
+ public boolean isNaN() {
+ return isNaN(value);
+ }
+
+ /**
+ * Return <code>true</code> if the value of this <code>Double</code> is the
+ * same as <code>NEGATIVE_INFINITY</code> or <code>POSITIVE_INFINITY</code>,
+ * otherwise return <code>false</code>.
+ *
+ * @return whether this <code>Double</code> is (-/+) infinity
+ */
+ public boolean isInfinite() {
+ return isInfinite(value);
+ }
+
+ /**
+ * Convert the <code>double</code> value of this <code>Double</code> to a
+ * <code>String</code>. This method calls <code>Double.toString(double)</code>
+ * to do its dirty work.
+ *
+ * @return the <code>String</code> representation
+ * @see #toString(double)
+ */
+ public String toString() {
+ return toString(value);
+ }
+
+ /**
+ * Return the value of this <code>Double</code> as a <code>byte</code>.
+ *
+ * @return the byte value
+ * @since 1.1
+ */
+ public byte byteValue() {
+ return (byte) value;
+ }
+
+ /**
+ * Return the value of this <code>Double</code> as a <code>short</code>.
+ *
+ * @return the short value
+ * @since 1.1
+ */
+ public short shortValue() {
+ return (short) value;
+ }
+
+ /**
+ * Return the value of this <code>Double</code> as an <code>int</code>.
+ *
+ * @return the int value
+ */
+ public int intValue() {
+ return (int) value;
+ }
+
+ /**
+ * Return the value of this <code>Double</code> as a <code>long</code>.
+ *
+ * @return the long value
+ */
+ public long longValue() {
+ return (long) value;
+ }
+
+ /**
+ * Return the value of this <code>Double</code> as a <code>float</code>.
+ *
+ * @return the float value
+ */
+ public float floatValue() {
+ return (float) value;
+ }
+
+ /**
+ * Return the value of this <code>Double</code>.
+ *
+ * @return the double value
+ */
+ public double doubleValue() {
+ return value;
+ }
+
+ /**
+ * Return a hashcode representing this Object. <code>Double</code>'s hash code
+ * is calculated by:<br>
+ * <code>long v = Double.doubleToLongBits(doubleValue());<br>
+ * int hash = (int)(v^(v>>32))</code>.
+ *
+ * @return this Object's hash code
+ * @see #doubleToLongBits(double)
+ */
+ public int hashCode() {
+ long v = doubleToLongBits(value);
+ return (int) (v ^ (v >>> 32));
+ }
+
+ /**
+ * Returns <code>true</code> if <code>obj</code> is an instance of
+ * <code>Double</code> and represents the same double value. Unlike comparing
+ * two doubles with <code>==</code>, this treats two instances of
+ * <code>Double.NaN</code> as equal, but treats <code>0.0</code> and
+ * <code>-0.0</code> as unequal.
+ *
+ * <p>
+ * Note that <code>d1.equals(d2)</code> is identical to
+ * <code>doubleToLongBits(d1.doubleValue()) ==
+ * doubleToLongBits(d2.doubleValue())</code>.
+ *
+ * @param obj
+ * the object to compare
+ * @return whether the objects are semantically equal
+ */
+ public boolean equals(Object obj) {
+ if (!(obj instanceof Double))
+ return false;
+
+ double d = ((Double) obj).value;
+
+ // Avoid call to native method. However, some implementations, like gcj,
+ // are better off using floatToIntBits(value) == floatToIntBits(f).
+ // Check common case first, then check NaN and 0.
+ if (value == d)
+ return (value != 0) || (1 / value == 1 / d);
+ return isNaN(value) && isNaN(d);
+ }
+
+ /**
+ * Convert the double to the IEEE 754 floating-point "double format" bit
+ * layout. Bit 63 (the most significant) is the sign bit, bits 62-52 (masked
+ * by 0x7ff0000000000000L) represent the exponent, and bits 51-0 (masked by
+ * 0x000fffffffffffffL) are the mantissa. This function collapses all versions
+ * of NaN to 0x7ff8000000000000L. The result of this function can be used as
+ * the argument to <code>Double.longBitsToDouble(long)</code> to obtain the
+ * original <code>double</code> value.
+ *
+ * @param value
+ * the <code>double</code> to convert
+ * @return the bits of the <code>double</code>
+ * @see #longBitsToDouble(long)
+ */
+ public static long doubleToLongBits(double value) {
+ if (isNaN(value))
+ return 0x7ff8000000000000L;
+ else
+ return /* VMDouble. */doubleToRawLongBits(value);
+ }
+
+ /**
+ * Convert the double to the IEEE 754 floating-point "double format" bit
+ * layout. Bit 63 (the most significant) is the sign bit, bits 62-52 (masked
+ * by 0x7ff0000000000000L) represent the exponent, and bits 51-0 (masked by
+ * 0x000fffffffffffffL) are the mantissa. This function leaves NaN alone,
+ * rather than collapsing to a canonical value. The result of this function
+ * can be used as the argument to <code>Double.longBitsToDouble(long)</code>
+ * to obtain the original <code>double</code> value.
+ *
+ * @param value
+ * the <code>double</code> to convert
+ * @return the bits of the <code>double</code>
+ * @see #longBitsToDouble(long)
+ */
+ /*
+ * public static long doubleToRawLongBits(double value) { return
+ * VMDouble.doubleToRawLongBits(value); }
+ */
+ public static native long doubleToRawLongBits(double value);
+
+ /**
+ * Convert the argument in IEEE 754 floating-point "double format" bit layout
+ * to the corresponding float. Bit 63 (the most significant) is the sign bit,
+ * bits 62-52 (masked by 0x7ff0000000000000L) represent the exponent, and bits
+ * 51-0 (masked by 0x000fffffffffffffL) are the mantissa. This function leaves
+ * NaN alone, so that you can recover the bit pattern with
+ * <code>Double.doubleToRawLongBits(double)</code>.
+ *
+ * @param bits
+ * the bits to convert
+ * @return the <code>double</code> represented by the bits
+ * @see #doubleToLongBits(double)
+ * @see #doubleToRawLongBits(double)
+ */
+ /*
+ * public static double longBitsToDouble(long bits) { return
+ * VMDouble.longBitsToDouble(bits); }
+ */
+ public static native double longBitsToDouble(long bits);
+
+ /**
+ * Compare two Doubles numerically by comparing their <code>double</code>
+ * values. The result is positive if the first is greater, negative if the
+ * second is greater, and 0 if the two are equal. However, this special cases
+ * NaN and signed zero as follows: NaN is considered greater than all other
+ * doubles, including <code>POSITIVE_INFINITY</code>, and positive zero is
+ * considered greater than negative zero.
+ *
+ * @param d
+ * the Double to compare
+ * @return the comparison
+ * @since 1.2
+ */
+ public int compareTo(Double d) {
+ return compare(value, d.value);
+ }
+
+ /**
+ * Behaves like <code>new Double(x).compareTo(new Double(y))</code>; in other
+ * words this compares two doubles, special casing NaN and zero, without the
+ * overhead of objects.
+ *
+ * @param x
+ * the first double to compare
+ * @param y
+ * the second double to compare
+ * @return the comparison
+ * @since 1.4
+ */
+ public static int compare(double x, double y) {
+ // handle the easy cases:
+ if (x < y)
+ return -1;
+ if (x > y)
+ return 1;
+
+ // handle equality respecting that 0.0 != -0.0 (hence not using x == y):
+ long lx = doubleToRawLongBits(x);
+ long ly = doubleToRawLongBits(y);
+ if (lx == ly)
+ return 0;
+
+ // handle NaNs:
+ if (x != x)
+ return (y != y) ? 0 : 1;
+ else if (y != y)
+ return -1;
+
+ // handle +/- 0.0
+ return (lx < ly) ? -1 : 1;
+ }
+}
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