rt/emul/compact/src/main/java/java/io/Bits.java
author Jaroslav Tulach <jaroslav.tulach@apidesign.org>
Tue, 26 Feb 2013 16:54:16 +0100
changeset 772 d382dacfd73f
parent 601 emul/compact/src/main/java/java/io/Bits.java@5198affdb915
permissions -rw-r--r--
Moving modules around so the runtime is under one master pom and can be built without building other modules that are in the repository
     1 /*
     2  * Copyright (c) 2001, 2010, Oracle and/or its affiliates. All rights reserved.
     3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
     4  *
     5  * This code is free software; you can redistribute it and/or modify it
     6  * under the terms of the GNU General Public License version 2 only, as
     7  * published by the Free Software Foundation.  Oracle designates this
     8  * particular file as subject to the "Classpath" exception as provided
     9  * by Oracle in the LICENSE file that accompanied this code.
    10  *
    11  * This code is distributed in the hope that it will be useful, but WITHOUT
    12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
    13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
    14  * version 2 for more details (a copy is included in the LICENSE file that
    15  * accompanied this code).
    16  *
    17  * You should have received a copy of the GNU General Public License version
    18  * 2 along with this work; if not, write to the Free Software Foundation,
    19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
    20  *
    21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
    22  * or visit www.oracle.com if you need additional information or have any
    23  * questions.
    24  */
    25 
    26 package java.io;
    27 
    28 /**
    29  * Utility methods for packing/unpacking primitive values in/out of byte arrays
    30  * using big-endian byte ordering.
    31  */
    32 class Bits {
    33 
    34     /*
    35      * Methods for unpacking primitive values from byte arrays starting at
    36      * given offsets.
    37      */
    38 
    39     static boolean getBoolean(byte[] b, int off) {
    40         return b[off] != 0;
    41     }
    42 
    43     static char getChar(byte[] b, int off) {
    44         return (char) ((b[off + 1] & 0xFF) +
    45                        (b[off] << 8));
    46     }
    47 
    48     static short getShort(byte[] b, int off) {
    49         return (short) ((b[off + 1] & 0xFF) +
    50                         (b[off] << 8));
    51     }
    52 
    53     static int getInt(byte[] b, int off) {
    54         return ((b[off + 3] & 0xFF)      ) +
    55                ((b[off + 2] & 0xFF) <<  8) +
    56                ((b[off + 1] & 0xFF) << 16) +
    57                ((b[off    ]       ) << 24);
    58     }
    59 
    60     static float getFloat(byte[] b, int off) {
    61         return Float.intBitsToFloat(getInt(b, off));
    62     }
    63 
    64     static long getLong(byte[] b, int off) {
    65         return ((b[off + 7] & 0xFFL)      ) +
    66                ((b[off + 6] & 0xFFL) <<  8) +
    67                ((b[off + 5] & 0xFFL) << 16) +
    68                ((b[off + 4] & 0xFFL) << 24) +
    69                ((b[off + 3] & 0xFFL) << 32) +
    70                ((b[off + 2] & 0xFFL) << 40) +
    71                ((b[off + 1] & 0xFFL) << 48) +
    72                (((long) b[off])      << 56);
    73     }
    74 
    75     static double getDouble(byte[] b, int off) {
    76         return Double.longBitsToDouble(getLong(b, off));
    77     }
    78 
    79     /*
    80      * Methods for packing primitive values into byte arrays starting at given
    81      * offsets.
    82      */
    83 
    84     static void putBoolean(byte[] b, int off, boolean val) {
    85         b[off] = (byte) (val ? 1 : 0);
    86     }
    87 
    88     static void putChar(byte[] b, int off, char val) {
    89         b[off + 1] = (byte) (val      );
    90         b[off    ] = (byte) (val >>> 8);
    91     }
    92 
    93     static void putShort(byte[] b, int off, short val) {
    94         b[off + 1] = (byte) (val      );
    95         b[off    ] = (byte) (val >>> 8);
    96     }
    97 
    98     static void putInt(byte[] b, int off, int val) {
    99         b[off + 3] = (byte) (val       );
   100         b[off + 2] = (byte) (val >>>  8);
   101         b[off + 1] = (byte) (val >>> 16);
   102         b[off    ] = (byte) (val >>> 24);
   103     }
   104 
   105     static void putFloat(byte[] b, int off, float val) {
   106         putInt(b, off,  Float.floatToIntBits(val));
   107     }
   108 
   109     static void putLong(byte[] b, int off, long val) {
   110         b[off + 7] = (byte) (val       );
   111         b[off + 6] = (byte) (val >>>  8);
   112         b[off + 5] = (byte) (val >>> 16);
   113         b[off + 4] = (byte) (val >>> 24);
   114         b[off + 3] = (byte) (val >>> 32);
   115         b[off + 2] = (byte) (val >>> 40);
   116         b[off + 1] = (byte) (val >>> 48);
   117         b[off    ] = (byte) (val >>> 56);
   118     }
   119 
   120     static void putDouble(byte[] b, int off, double val) {
   121         putLong(b, off, Double.doubleToLongBits(val));
   122     }
   123 }