| /* VMDouble.java -- VM Specific Double methods |
| Copyright (C) 2003, 2005, 2010 Free Software Foundation, Inc. |
| |
| This file is part of GNU Classpath. |
| |
| GNU Classpath is free software; you can redistribute it and/or modify |
| it under the terms of the GNU General Public License as published by |
| the Free Software Foundation; either version 2, or (at your option) |
| any later version. |
| |
| GNU Classpath 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 for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with GNU Classpath; see the file COPYING. If not, write to the |
| Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA |
| 02110-1301 USA. |
| |
| Linking this library statically or dynamically with other modules is |
| making a combined work based on this library. Thus, the terms and |
| conditions of the GNU General Public License cover the whole |
| combination. |
| |
| As a special exception, the copyright holders of this library give you |
| permission to link this library with independent modules to produce an |
| executable, regardless of the license terms of these independent |
| modules, and to copy and distribute the resulting executable under |
| terms of your choice, provided that you also meet, for each linked |
| independent module, the terms and conditions of the license of that |
| module. An independent module is a module which is not derived from |
| or based on this library. If you modify this library, you may extend |
| this exception to your version of the library, but you are not |
| obligated to do so. If you do not wish to do so, delete this |
| exception statement from your version. */ |
| |
| package java.lang; |
| |
| import gnu.classpath.Configuration; |
| |
| /* |
| * This class is a reference version, mainly for compiling a class library |
| * jar. It is likely that VM implementers replace this with their own |
| * version that can communicate effectively with the VM. |
| */ |
| |
| /** |
| * Code relocated from java.lang.Double by |
| * @author Dave Grove (groved@us.ibm.com) |
| */ |
| final class VMDouble |
| { |
| |
| /** |
| * Load native routines necessary for this class. |
| */ |
| static |
| { |
| if (Configuration.INIT_LOAD_LIBRARY) |
| { |
| System.loadLibrary("javalang"); |
| } |
| |
| initIDs(); |
| } |
| |
| private VMDouble() {} // Prohibits instantiation. |
| |
| /** |
| * Convert the double to the IEEE 754 floating-point "double format" bit |
| * layout. Bit 63 (the most significant) is the sign bit, bits 62-52 |
| * (masked by 0x7ff0000000000000L) represent the exponent, and bits 51-0 |
| * (masked by 0x000fffffffffffffL) are the mantissa. This function |
| * leaves NaN alone, rather than collapsing to a canonical value. The |
| * result of this function can be used as the argument to |
| * <code>Double.longBitsToDouble(long)</code> to obtain the original |
| * <code>double</code> value. |
| * |
| * @param value the <code>double</code> to convert |
| * @return the bits of the <code>double</code> |
| * @see #longBitsToDouble(long) |
| */ |
| static native long doubleToRawLongBits(double value); |
| |
| /** |
| * Convert the argument in IEEE 754 floating-point "double format" bit |
| * layout to the corresponding float. Bit 63 (the most significant) is the |
| * sign bit, bits 62-52 (masked by 0x7ff0000000000000L) represent the |
| * exponent, and bits 51-0 (masked by 0x000fffffffffffffL) are the mantissa. |
| * This function leaves NaN alone, so that you can recover the bit pattern |
| * with <code>Double.doubleToRawLongBits(double)</code>. |
| * |
| * @param bits the bits to convert |
| * @return the <code>double</code> represented by the bits |
| * @see #doubleToLongBits(double) |
| * @see #doubleToRawLongBits(double) |
| */ |
| static native double longBitsToDouble(long bits); |
| |
| /** |
| * Helper method to convert to string. |
| * |
| * @param d the double to convert |
| * @param isFloat true if the conversion is requested by Float (results in |
| * fewer digits) |
| */ |
| static native String toString(double d, boolean isFloat); |
| |
| /** |
| * Initialize JNI cache. This method is called only by the |
| * static initializer when using JNI. |
| */ |
| private static native void initIDs(); |
| |
| /** |
| * Parse the specified String as a double. |
| * @throws NumberFormatException if str cannot be parsed |
| * @throws NullPointerException if str is null |
| */ |
| static native double parseDouble(String str); |
| } |