--- /dev/null 2014-08-20 17:35:36.000000000 +0800 +++ new/test/java/lang/Math/FloatConsts.java 2014-08-20 17:35:36.000000000 +0800 @@ -0,0 +1,74 @@ +/* + * Copyright (c) 2003, 2014, 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. + * + * 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. + */ + +/** + * Common library for additional constants of the {@code float} type. + */ +public final class FloatConsts { + /** + * Don't let anyone instantiate this class. + */ + private FloatConsts() {} + + /** + * Bias used in representing a {@code float} exponent. + */ + public static final int EXP_BIAS = 127; + + /** + * Bit mask to isolate the exponent field of a {@code float}. + */ + public static final int EXP_BIT_MASK = 0x7F800000; + + /** + * Bit mask to isolate the sign bit of a {@code float}. + */ + public static final int SIGN_BIT_MASK = 0x80000000; + + /** + * Bit mask to isolate the significand field of a {@code float}. + */ + public static final int SIGNIF_BIT_MASK = 0x007FFFFF; + + /** + * The number of logical bits in the significand of a + * {@code float} number, including the implicit bit. + */ + public static final int SIGNIFICAND_WIDTH = 24; + + /** + * The exponent the smallest positive {@code float} subnormal + * value would have if it could be normalized. + */ + public static final int MIN_SUB_EXPONENT = Float.MIN_EXPONENT - + (SIGNIFICAND_WIDTH - 1); + + 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) == ~0) && + (((SIGN_BIT_MASK & EXP_BIT_MASK) == 0) && + ((SIGN_BIT_MASK & SIGNIF_BIT_MASK) == 0) && + ((EXP_BIT_MASK & SIGNIF_BIT_MASK) == 0))); + } +}