151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski/* 251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * Copyright (c) 2003, Oracle and/or its affiliates. All rights reserved. 351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * 551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * This code is free software; you can redistribute it and/or modify it 651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * under the terms of the GNU General Public License version 2 only, as 751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * published by the Free Software Foundation. Oracle designates this 851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * particular file as subject to the "Classpath" exception as provided 951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * by Oracle in the LICENSE file that accompanied this code. 1051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * 1151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * This code is distributed in the hope that it will be useful, but WITHOUT 1251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 1351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 1451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * version 2 for more details (a copy is included in the LICENSE file that 1551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * accompanied this code). 1651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * 1751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * You should have received a copy of the GNU General Public License version 1851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * 2 along with this work; if not, write to the Free Software Foundation, 1951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 2051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * 2151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 2251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * or visit www.oracle.com if you need additional information or have any 2351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * questions. 2451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski */ 2551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski 2651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebskipackage sun.misc; 2751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski 2851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski/** 2951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * This class contains additional constants documenting limits of the 3051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * <code>double</code> type. 3151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * 3251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * @author Joseph D. Darcy 3351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski */ 3451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski 3551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebskipublic class DoubleConsts { 3651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski /** 3751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * Don't let anyone instantiate this class. 3851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski */ 3951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski private DoubleConsts() {} 4051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski 4151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski public static final double POSITIVE_INFINITY = java.lang.Double.POSITIVE_INFINITY; 4251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski public static final double NEGATIVE_INFINITY = java.lang.Double.NEGATIVE_INFINITY; 4351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski public static final double NaN = java.lang.Double.NaN; 4451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski public static final double MAX_VALUE = java.lang.Double.MAX_VALUE; 4551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski public static final double MIN_VALUE = java.lang.Double.MIN_VALUE; 4651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski 4751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski /** 4851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * A constant holding the smallest positive normal value of type 4951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * <code>double</code>, 2<sup>-1022</sup>. It is equal to the 5051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * value returned by 5151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * <code>Double.longBitsToDouble(0x0010000000000000L)</code>. 5251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * 5351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * @since 1.5 5451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski */ 5551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski public static final double MIN_NORMAL = 2.2250738585072014E-308; 5651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski 5751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski 5851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski /** 5951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * The number of logical bits in the significand of a 6051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * <code>double</code> number, including the implicit bit. 6151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski */ 6251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski public static final int SIGNIFICAND_WIDTH = 53; 6351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski 6451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski /** 6551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * Maximum exponent a finite <code>double</code> number may have. 6651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * It is equal to the value returned by 6751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * <code>Math.ilogb(Double.MAX_VALUE)</code>. 6851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski */ 6951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski public static final int MAX_EXPONENT = 1023; 7051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski 7151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski /** 7251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * Minimum exponent a normalized <code>double</code> number may 7351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * have. It is equal to the value returned by 7451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * <code>Math.ilogb(Double.MIN_NORMAL)</code>. 7551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski */ 7651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski public static final int MIN_EXPONENT = -1022; 7751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski 7851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski /** 7951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * The exponent the smallest positive <code>double</code> 8051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * subnormal value would have if it could be normalized. It is 8151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * equal to the value returned by 8251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * <code>FpUtils.ilogb(Double.MIN_VALUE)</code>. 8351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski */ 8451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski public static final int MIN_SUB_EXPONENT = MIN_EXPONENT - 8551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski (SIGNIFICAND_WIDTH - 1); 8651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski 8751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski /** 8851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * Bias used in representing a <code>double</code> exponent. 8951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski */ 9051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski public static final int EXP_BIAS = 1023; 9151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski 9251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski /** 9351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * Bit mask to isolate the sign bit of a <code>double</code>. 9451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski */ 9551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski public static final long SIGN_BIT_MASK = 0x8000000000000000L; 9651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski 9751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski /** 9851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * Bit mask to isolate the exponent field of a 9951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * <code>double</code>. 10051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski */ 10151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski public static final long EXP_BIT_MASK = 0x7FF0000000000000L; 10251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski 10351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski /** 10451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * Bit mask to isolate the significand field of a 10551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski * <code>double</code>. 10651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski */ 10751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski public static final long SIGNIF_BIT_MASK = 0x000FFFFFFFFFFFFFL; 10851b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski 10951b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski static { 11051b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski // verify bit masks cover all bit positions and that the bit 11151b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski // masks are non-overlapping 11251b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski assert(((SIGN_BIT_MASK | EXP_BIT_MASK | SIGNIF_BIT_MASK) == ~0L) && 11351b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski (((SIGN_BIT_MASK & EXP_BIT_MASK) == 0L) && 11451b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski ((SIGN_BIT_MASK & SIGNIF_BIT_MASK) == 0L) && 11551b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski ((EXP_BIT_MASK & SIGNIF_BIT_MASK) == 0L))); 11651b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski } 11751b1b6997fd3f980076b8081f7f1165ccc2a4008Piotr Jastrzebski} 118