38 lines
1.2 KiB
Java
38 lines
1.2 KiB
Java
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package com.wiredtiger.db;
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import java.lang.String;
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/*
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* Package-private - not part of the public API.
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*/
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class PackUtil {
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/* Contants. */
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final static byte NEG_MULTI_MARKER = (byte)0x10;
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final static byte NEG_2BYTE_MARKER = (byte)0x20;
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final static byte NEG_1BYTE_MARKER = (byte)0x40;
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final static byte POS_1BYTE_MARKER = (byte)0x80;
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final static byte POS_2BYTE_MARKER = (byte)0xc0;
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final static byte POS_MULTI_MARKER = (byte)0xe0;
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final static int NEG_1BYTE_MIN = ((-1) << 6);
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final static int NEG_2BYTE_MIN = (((-1) << 13) + NEG_1BYTE_MIN);
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final static int POS_1BYTE_MAX = ((1 << 6) - 1);
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final static int POS_2BYTE_MAX = ((1 << 13) + POS_1BYTE_MAX);
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// See: http://docs.python.org/2/library/struct.html for an explanation
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// of what these special characters mean.
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// TODO: Care about byte ordering and padding in packed formats.
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final static String PackSpecialCharacters = "@=<>!x";
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final static int SIZEOF_LONG = 8;
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/*
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* Extract bits <start> to <end> from a value (counting from LSB == 0).
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*/
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public static byte GET_BITS(long x, int start, int end) {
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return (byte)((x & ((1 << start) - 1)) >> end);
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}
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}
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