--- /dev/null
+/* Float.java -- object wrapper for float
+ 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. */
+
+/**
+ * Instances of class <code>Float</code> represent primitive <code>float</code>
+ * values.
+ *
+ * Additionally, this class provides various helper functions and variables
+ * related to floats.
+ *
+ * @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 Float {
+ /**
+ * Compatible with JDK 1.0+.
+ */
+ private static final long serialVersionUID = -2671257302660747028L;
+
+ /**
+ * The maximum positive value a <code>double</code> may represent is
+ * 3.4028235e+38f.
+ */
+ public static final float MAX_VALUE = 3.4028235e+38f;
+
+ /**
+ * The minimum positive value a <code>float</code> may represent is 1.4e-45.
+ */
+ public static final float MIN_VALUE = 1.4e-45f;
+
+ /**
+ * The value of a float representation -1.0/0.0, negative infinity.
+ */
+ public static final float NEGATIVE_INFINITY = -1.0f / 0.0f;
+
+ /**
+ * The value of a float representation 1.0/0.0, positive infinity.
+ */
+ public static final float POSITIVE_INFINITY = 1.0f / 0.0f;
+
+ /**
+ * All IEEE 754 values of NaN have the same value in Java.
+ */
+ public static final float NaN = 0.0f / 0.0f;
+
+ /**
+ * The primitive type <code>float</code> is represented by this
+ * <code>Class</code> object.
+ *
+ * @since 1.1
+ */
+ // public static final Class<Float> TYPE = (Class<Float>)
+ // VMClassLoader.getPrimitiveClass('F');
+
+ /**
+ * The number of bits needed to represent a <code>float</code>.
+ *
+ * @since 1.5
+ */
+ public static final int SIZE = 32;
+
+ /**
+ * Cache representation of 0
+ */
+ private static final Float ZERO = new Float(0.0f);
+
+ /**
+ * Cache representation of 1
+ */
+ private static final Float ONE = new Float(1.0f);
+
+ /**
+ * The immutable value of this Float.
+ *
+ * @serial the wrapped float
+ */
+ private final float value;
+
+ /**
+ * Create a <code>Float</code> from the primitive <code>float</code>
+ * specified.
+ *
+ * @param value
+ * the <code>float</code> argument
+ */
+ public Float(float value) {
+ this.value = value;
+ }
+
+ /**
+ * Create a <code>Float</code> from the primitive <code>double</code>
+ * specified.
+ *
+ * @param value
+ * the <code>double</code> argument
+ */
+ public Float(double value) {
+ this.value = (float) value;
+ }
+
+ /**
+ * Create a <code>Float</code> from the specified <code>String</code>. This
+ * method calls <code>Float.parseFloat()</code>.
+ *
+ * @param s
+ * the <code>String</code> to convert
+ * @throws NumberFormatException
+ * if <code>s</code> cannot be parsed as a <code>float</code>
+ * @throws NullPointerException
+ * if <code>s</code> is null
+ * @see #parseFloat(String)
+ */
+ public Float(String s) {
+ value = parseFloat(s);
+ }
+
+ /**
+ * Convert the <code>float</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 Float</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
+ * float.
+ *
+ * <p>
+ * To create other output formats, use {@link java.text.NumberFormat}.
+ *
+ * @XXX specify where we are not in accord with the spec.
+ *
+ * @param f
+ * the <code>float</code> to convert
+ * @return the <code>String</code> representing the <code>float</code>
+ */
+ /*
+ * public static String toString(float f) { return VMFloat.toString(f); }
+ */
+
+ /**
+ * Convert a float 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 f
+ * the float value
+ * @return the hexadecimal string representation
+ * @since 1.5
+ */
+ /*
+ * public static String toHexString(float f) { if (isNaN(f)) return "NaN"; if
+ * (isInfinite(f)) return f < 0 ? "-Infinity" : "Infinity";
+ *
+ * int bits = floatToIntBits(f); CPStringBuilder result = new
+ * CPStringBuilder();
+ *
+ * if (bits < 0) result.append('-'); result.append("0x");
+ *
+ * final int mantissaBits = 23; final int exponentBits = 8; int mantMask = (1
+ * << mantissaBits) - 1; int mantissa = bits & mantMask; int expMask = (1 <<
+ * exponentBits) - 1; int exponent = (bits >>> mantissaBits) & expMask;
+ *
+ * result.append(exponent == 0 ? '0' : '1'); result.append('.'); // For Float
+ * only, we have to adjust the mantissa. mantissa <<= 1;
+ * result.append(Integer.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(Integer.toString(exponent)); return result.toString(); }
+ */
+
+ /**
+ * Creates a new <code>Float</code> object using the <code>String</code>.
+ *
+ * @param s
+ * the <code>String</code> to convert
+ * @return the new <code>Float</code>
+ * @throws NumberFormatException
+ * if <code>s</code> cannot be parsed as a <code>float</code>
+ * @throws NullPointerException
+ * if <code>s</code> is null
+ * @see #parseFloat(String)
+ */
+ public static Float valueOf(String s) {
+ return valueOf(parseFloat(s));
+ }
+
+ /**
+ * Returns a <code>Float</code> object wrapping the value. In contrast to the
+ * <code>Float</code> constructor, this method may cache some values. It is
+ * used by boxing conversion.
+ *
+ * @param val
+ * the value to wrap
+ * @return the <code>Float</code>
+ * @since 1.5
+ */
+ public static Float valueOf(float val) {
+ if ((val == 0.0)/* && (floatToRawIntBits(val) == 0) */)
+ return ZERO;
+ else if (val == 1.0)
+ return ONE;
+ else
+ return new Float(val);
+ }
+
+ /**
+ * Parse the specified <code>String</code> as a <code>float</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 float. 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>float</code> value of <code>s</code>
+ * @throws NumberFormatException
+ * if <code>str</code> cannot be parsed as a <code>float</code>
+ * @throws NullPointerException
+ * if <code>str</code> is null
+ * @see #MIN_VALUE
+ * @see #MAX_VALUE
+ * @see #POSITIVE_INFINITY
+ * @see #NEGATIVE_INFINITY
+ * @since 1.2
+ */
+ public static float parseFloat(String str) {
+ // return VMFloat.parseFloat(str);
+ return (float) (Double.parseDouble(str));
+ }
+
+ /**
+ * Return <code>true</code> if the <code>float</code> has the same value as
+ * <code>NaN</code>, otherwise return <code>false</code>.
+ *
+ * @param v
+ * the <code>float</code> to compare
+ * @return whether the argument is <code>NaN</code>
+ */
+ public static boolean isNaN(float 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>float</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>float</code> to compare
+ * @return whether the argument is (-/+) infinity
+ */
+ public static boolean isInfinite(float v) {
+ return v == POSITIVE_INFINITY || v == NEGATIVE_INFINITY;
+ }
+
+ /**
+ * Return <code>true</code> if the value of this <code>Float</code> is the
+ * same as <code>NaN</code>, otherwise return <code>false</code>.
+ *
+ * @return whether this <code>Float</code> is <code>NaN</code>
+ */
+ public boolean isNaN() {
+ return isNaN(value);
+ }
+
+ /**
+ * Return <code>true</code> if the value of this <code>Float</code> is the
+ * same as <code>NEGATIVE_INFINITY</code> or <code>POSITIVE_INFINITY</code>,
+ * otherwise return <code>false</code>.
+ *
+ * @return whether this <code>Float</code> is (-/+) infinity
+ */
+ public boolean isInfinite() {
+ return isInfinite(value);
+ }
+
+ /**
+ * Convert the <code>float</code> value of this <code>Float</code> to a
+ * <code>String</code>. This method calls <code>Float.toString(float)</code>
+ * to do its dirty work.
+ *
+ * @return the <code>String</code> representation
+ * @see #toString(float)
+ */
+ /*
+ * public String toString() { return toString(value); }
+ */
+
+ /**
+ * Return the value of this <code>Float</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>Float</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>Integer</code> as an <code>int</code>.
+ *
+ * @return the int value
+ */
+ public int intValue() {
+ return (int) value;
+ }
+
+ /**
+ * Return the value of this <code>Integer</code> as a <code>long</code>.
+ *
+ * @return the long value
+ */
+ public long longValue() {
+ return (long) value;
+ }
+
+ /**
+ * Return the value of this <code>Float</code>.
+ *
+ * @return the float value
+ */
+ public float floatValue() {
+ return value;
+ }
+
+ /**
+ * Return the value of this <code>Float</code> as a <code>double</code>
+ *
+ * @return the double value
+ */
+ public double doubleValue() {
+ return value;
+ }
+
+ /**
+ * Return a hashcode representing this Object. <code>Float</code>'s hash code
+ * is calculated by calling <code>floatToIntBits(floatValue())</code>.
+ *
+ * @return this Object's hash code
+ * @see #floatToIntBits(float)
+ */
+ /*
+ * public int hashCode() { return floatToIntBits(value); }
+ */
+
+ /**
+ * Returns <code>true</code> if <code>obj</code> is an instance of
+ * <code>Float</code> and represents the same float value. Unlike comparing
+ * two floats with <code>==</code>, this treats two instances of
+ * <code>Float.NaN</code> as equal, but treats <code>0.0</code> and
+ * <code>-0.0</code> as unequal.
+ *
+ * <p>
+ * Note that <code>f1.equals(f2)</code> is identical to
+ * <code>floatToIntBits(f1.floatValue()) ==
+ * floatToIntBits(f2.floatValue())</code>.
+ *
+ * @param obj
+ * the object to compare
+ * @return whether the objects are semantically equal
+ */
+ /*
+ * public boolean equals(Object obj) { if (obj instanceof Float) { float f =
+ * ((Float) obj).value; return (floatToRawIntBits(value) ==
+ * floatToRawIntBits(f)) || (isNaN(value) && isNaN(f)); } return false; }
+ */
+
+ /**
+ * Convert the float to the IEEE 754 floating-point "single format" bit
+ * layout. Bit 31 (the most significant) is the sign bit, bits 30-23 (masked
+ * by 0x7f800000) represent the exponent, and bits 22-0 (masked by 0x007fffff)
+ * are the mantissa. This function collapses all versions of NaN to
+ * 0x7fc00000. The result of this function can be used as the argument to
+ * <code>Float.intBitsToFloat(int)</code> to obtain the original
+ * <code>float</code> value.
+ *
+ * @param value
+ * the <code>float</code> to convert
+ * @return the bits of the <code>float</code>
+ * @see #intBitsToFloat(int)
+ */
+ /*
+ * public static int floatToIntBits(float value) { if (isNaN(value)) return
+ * 0x7fc00000; else return VMFloat.floatToRawIntBits(value); }
+ */
+
+ /**
+ * Convert the float to the IEEE 754 floating-point "single format" bit
+ * layout. Bit 31 (the most significant) is the sign bit, bits 30-23 (masked
+ * by 0x7f800000) represent the exponent, and bits 22-0 (masked by 0x007fffff)
+ * 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>Float.intBitsToFloat(int)</code> to obtain the original
+ * <code>float</code> value.
+ *
+ * @param value
+ * the <code>float</code> to convert
+ * @return the bits of the <code>float</code>
+ * @see #intBitsToFloat(int)
+ */
+ /*
+ * public static int floatToRawIntBits(float value) { return
+ * VMFloat.floatToRawIntBits(value); }
+ */
+
+ /**
+ * Convert the argument in IEEE 754 floating-point "single format" bit layout
+ * to the corresponding float. Bit 31 (the most significant) is the sign bit,
+ * bits 30-23 (masked by 0x7f800000) represent the exponent, and bits 22-0
+ * (masked by 0x007fffff) are the mantissa. This function leaves NaN alone, so
+ * that you can recover the bit pattern with
+ * <code>Float.floatToRawIntBits(float)</code>.
+ *
+ * @param bits
+ * the bits to convert
+ * @return the <code>float</code> represented by the bits
+ * @see #floatToIntBits(float)
+ * @see #floatToRawIntBits(float)
+ */
+ /*
+ * public static float intBitsToFloat(int bits) { return
+ * VMFloat.intBitsToFloat(bits); }
+ */
+
+ /**
+ * Compare two Floats numerically by comparing their <code>float</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
+ * floats, including <code>POSITIVE_INFINITY</code>, and positive zero is
+ * considered greater than negative zero.
+ *
+ * @param f
+ * the Float to compare
+ * @return the comparison
+ * @since 1.2
+ */
+ /*
+ * public int compareTo(Float f) { return compare(value, f.value); }
+ */
+
+ /**
+ * Behaves like <code>new Float(x).compareTo(new Float(y))</code>; in other
+ * words this compares two floats, special casing NaN and zero, without the
+ * overhead of objects.
+ *
+ * @param x
+ * the first float to compare
+ * @param y
+ * the second float to compare
+ * @return the comparison
+ * @since 1.4
+ */
+ /*
+ * public static int compare(float x, float 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):
+ * int ix = floatToRawIntBits(x); int iy = floatToRawIntBits(y); if (ix == iy)
+ * return 0;
+ *
+ * // handle NaNs: if (x != x) return (y != y) ? 0 : 1; else if (y != y)
+ * return -1;
+ *
+ * // handle +/- 0.0 return (ix < iy) ? -1 : 1; }
+ */
+}
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