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/*
* Copyright (c) 2003, 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 sun.misc;
/**
* This class contains additional constants documenting limits of the
* <code>double</code> type.
*
* @author Joseph D. Darcy
*/
public class DoubleConsts {
/**
* Don't let anyone instantiate this class.
*/
private DoubleConsts() {}
public static final double POSITIVE_INFINITY = java.lang.Double.POSITIVE_INFINITY;
public static final double NEGATIVE_INFINITY = java.lang.Double.NEGATIVE_INFINITY;
public static final double NaN = java.lang.Double.NaN;
public static final double MAX_VALUE = java.lang.Double.MAX_VALUE;
public static final double MIN_VALUE = java.lang.Double.MIN_VALUE;
/**
* A constant holding the smallest positive normal value of type
* <code>double</code>, 2<sup>-1022</sup>. It is equal to the
* value returned by
* <code>Double.longBitsToDouble(0x0010000000000000L)</code>.
*
* @since 1.5
*/
public static final double MIN_NORMAL = 2.2250738585072014E-308;
/**
* The number of logical bits in the significand of a
* <code>double</code> number, including the implicit bit.
*/
public static final int SIGNIFICAND_WIDTH = 53;
/**
* Maximum exponent a finite <code>double</code> number may have.
* It is equal to the value returned by
* <code>Math.ilogb(Double.MAX_VALUE)</code>.
*/
public static final int MAX_EXPONENT = 1023;
/**
* Minimum exponent a normalized <code>double</code> number may
* have. It is equal to the value returned by
* <code>Math.ilogb(Double.MIN_NORMAL)</code>.
*/
public static final int MIN_EXPONENT = -1022;
/**
* The exponent the smallest positive <code>double</code>
* subnormal value would have if it could be normalized. It is
* equal to the value returned by
* <code>FpUtils.ilogb(Double.MIN_VALUE)</code>.
*/
public static final int MIN_SUB_EXPONENT = MIN_EXPONENT -
(SIGNIFICAND_WIDTH - 1);
/**
* Bias used in representing a <code>double</code> exponent.
*/
public static final int EXP_BIAS = 1023;
/**
* Bit mask to isolate the sign bit of a <code>double</code>.
*/
public static final long SIGN_BIT_MASK = 0x8000000000000000L;
/**
* Bit mask to isolate the exponent field of a
* <code>double</code>.
*/
public static final long EXP_BIT_MASK = 0x7FF0000000000000L;
/**
* Bit mask to isolate the significand field of a
* <code>double</code>.
*/
public static final long SIGNIF_BIT_MASK = 0x000FFFFFFFFFFFFFL;
static {
// verify bit masks cover all bit positions and that the bit
// masks are non-overlapping
assert(((SIGN_BIT_MASK | EXP_BIT_MASK | SIGNIF_BIT_MASK) == ~0L) &&
(((SIGN_BIT_MASK & EXP_BIT_MASK) == 0L) &&
((SIGN_BIT_MASK & SIGNIF_BIT_MASK) == 0L) &&
((EXP_BIT_MASK & SIGNIF_BIT_MASK) == 0L)));
}
}
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