Java tutorial
//package com.java2s; /* * 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. */ import sun.misc.FloatConsts; import sun.misc.DoubleConsts; public class Main { /** * Returns unbiased exponent of a <code>double</code>. */ public static int getExponent(double d) { /* * Bitwise convert d to long, mask out exponent bits, shift * to the right and then subtract out double's bias adjust to * get true exponent value. */ return (int) (((Double.doubleToRawLongBits(d) & DoubleConsts.EXP_BIT_MASK) >> (DoubleConsts.SIGNIFICAND_WIDTH - 1)) - DoubleConsts.EXP_BIAS); } /** * Returns unbiased exponent of a <code>float</code>. */ public static int getExponent(float f) { /* * Bitwise convert f to integer, mask out exponent bits, shift * to the right and then subtract out float's bias adjust to * get true exponent value */ return ((Float.floatToRawIntBits(f) & FloatConsts.EXP_BIT_MASK) >> (FloatConsts.SIGNIFICAND_WIDTH - 1)) - FloatConsts.EXP_BIAS; } }