| /* |
| * Copyright (c) 2003, 2016, 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 jdk.internal.math; |
| |
| /** |
| * This class contains additional constants documenting limits of the |
| * {@code double} type. |
| * |
| * @author Joseph D. Darcy |
| */ |
| |
| public class DoubleConsts { |
| /** |
| * Don't let anyone instantiate this class. |
| */ |
| private DoubleConsts() {} |
| |
| /** |
| * The number of logical bits in the significand of a |
| * {@code double} number, including the implicit bit. |
| */ |
| public static final int SIGNIFICAND_WIDTH = 53; |
| |
| /** |
| * The exponent the smallest positive {@code double} |
| * subnormal value would have if it could be normalized.. |
| */ |
| public static final int MIN_SUB_EXPONENT = Double.MIN_EXPONENT - |
| (SIGNIFICAND_WIDTH - 1); |
| |
| /** |
| * Bias used in representing a {@code double} exponent. |
| */ |
| public static final int EXP_BIAS = 1023; |
| |
| /** |
| * Bit mask to isolate the sign bit of a {@code double}. |
| */ |
| public static final long SIGN_BIT_MASK = 0x8000000000000000L; |
| |
| /** |
| * Bit mask to isolate the exponent field of a |
| * {@code double}. |
| */ |
| public static final long EXP_BIT_MASK = 0x7FF0000000000000L; |
| |
| /** |
| * Bit mask to isolate the significand field of a |
| * {@code double}. |
| */ |
| 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))); |
| } |
| } |