endianutils.java

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     * converted to the opposed endian system while reading.
     * @param data source byte array
     * @param offset starting offset in the byte array
     * @return the value read
     */
    public static float readSwappedFloat(byte[] data, int offset) {
        return Float.intBitsToFloat( readSwappedInteger( data, offset ) );
    }

    /**
     * Writes a "double" value to a byte array at a given offset. The value is
     * converted to the opposed endian system while writing.
     * @param data target byte array
     * @param offset starting offset in the byte array
     * @param value value to write
     */
    public static void writeSwappedDouble(byte[] data, int offset, double value) {
        writeSwappedLong( data, offset, Double.doubleToLongBits( value ) );
    }

    /**
     * Reads a "double" value from a byte array at a given offset. The value is
     * converted to the opposed endian system while reading.
     * @param data source byte array
     * @param offset starting offset in the byte array
     * @return the value read
     */
    public static double readSwappedDouble(byte[] data, int offset) {
        return Double.longBitsToDouble( readSwappedLong( data, offset ) );
    }

    /**
     * Writes a "short" value to an OutputStream. The value is
     * converted to the opposed endian system while writing.
     * @param output target OutputStream
     * @param value value to write
     * @throws IOException in case of an I/O problem
     */
    public static void writeSwappedShort(OutputStream output, short value)
        throws IOException
    {
        output.write( (byte)( ( value >> 0 ) & 0xff ) );
        output.write( (byte)( ( value >> 8 ) & 0xff ) );
    }

    /**
     * Reads a "short" value from an InputStream. The value is
     * converted to the opposed endian system while reading.
     * @param input source InputStream
     * @return the value just read
     * @throws IOException in case of an I/O problem
     */
    public static short readSwappedShort(InputStream input)
        throws IOException
    {
        return (short)( ( ( read( input ) & 0xff ) << 0 ) +
            ( ( read( input ) & 0xff ) << 8 ) );
    }

    /**
     * Reads a unsigned short (16-bit) from an InputStream. The value is
     * converted to the opposed endian system while reading.
     * @param input source InputStream
     * @return the value just read
     * @throws IOException in case of an I/O problem
     */
    public static int readSwappedUnsignedShort(InputStream input)
        throws IOException
    {
        int value1 = read( input );
        int value2 = read( input );

        return (int)( ( ( value1 & 0xff ) << 0 ) +
            ( ( value2 & 0xff ) << 8 ) );
    }

    /**
     * Writes a "int" value to an OutputStream. The value is
     * converted to the opposed endian system while writing.
     * @param output target OutputStream
     * @param value value to write
     * @throws IOException in case of an I/O problem
     */
    public static void writeSwappedInteger(OutputStream output, int value)
        throws IOException
    {
        output.write( (byte)( ( value >> 0 ) & 0xff ) );
        output.write( (byte)( ( value >> 8 ) & 0xff ) );
        output.write( (byte)( ( value >> 16 ) & 0xff ) );
        output.write( (byte)( ( value >> 24 ) & 0xff ) );
    }

    /**
     * Reads a "int" value from an InputStream. The value is
     * converted to the opposed endian system while reading.
     * @param input source InputStream
     * @return the value just read
     * @throws IOException in case of an I/O problem
     */
    public static int readSwappedInteger(InputStream input)
        throws IOException
    {
        int value1 = read( input );
        int value2 = read( input );
        int value3 = read( input );
        int value4 = read( input );

        return (int)( ( ( value1 & 0xff ) << 0 ) +
            ( ( value2 & 0xff ) << 8 ) +
            ( ( value3 & 0xff ) << 16 ) +
            ( ( value4 & 0xff ) << 24 ) );
    }

    /**
     * Reads a unsigned integer (32-bit) from an InputStream. The value is
     * converted to the opposed endian system while reading.
     * @param input source InputStream
     * @return the value just read
     * @throws IOException in case of an I/O problem
     */
    public static long readSwappedUnsignedInteger(InputStream input)
        throws IOException
    {
        int value1 = read( input );
        int value2 = read( input );
        int value3 = read( input );
        int value4 = read( input );

        return (long)( ( ( value1 & 0xff ) << 0 ) +
            ( ( value2 & 0xff ) << 8 ) +
            ( ( value3 & 0xff ) << 16 ) +
            ( ( value4 & 0xff ) << 24 ) );
    }

    /**
     * Writes a "long" value to an OutputStream. The value is
     * converted to the opposed endian system while writing.
     * @param output target OutputStream
     * @param value value to write
     * @throws IOException in case of an I/O problem
     */
    public static void writeSwappedLong(OutputStream output, long value)
        throws IOException
    {
        output.write( (byte)( ( value >> 0 ) & 0xff ) );
        output.write( (byte)( ( value >> 8 ) & 0xff ) );
        output.write( (byte)( ( value >> 16 ) & 0xff ) );
        output.write( (byte)( ( value >> 24 ) & 0xff ) );
        output.write( (byte)( ( value >> 32 ) & 0xff ) );
        output.write( (byte)( ( value >> 40 ) & 0xff ) );
        output.write( (byte)( ( value >> 48 ) & 0xff ) );
        output.write( (byte)( ( value >> 56 ) & 0xff ) );
    }

    /**
     * Reads a "long" value from an InputStream. The value is
     * converted to the opposed endian system while reading.
     * @param input source InputStream
     * @return the value just read
     * @throws IOException in case of an I/O problem
     */
    public static long readSwappedLong(InputStream input)
        throws IOException
    {
        byte[] bytes = new byte[8];
        input.read( bytes );
        return readSwappedLong( bytes, 0 );
    }

    /**
     * Writes a "float" value to an OutputStream. The value is
     * converted to the opposed endian system while writing.
     * @param output target OutputStream
     * @param value value to write
     * @throws IOException in case of an I/O problem
     */
    public static void writeSwappedFloat(OutputStream output, float value)
        throws IOException
    {
        writeSwappedInteger( output, Float.floatToIntBits( value ) );
    }

    /**
     * Reads a "float" value from an InputStream. The value is
     * converted to the opposed endian system while reading.
     * @param input source InputStream
     * @return the value just read
     * @throws IOException in case of an I/O problem
     */
    public static float readSwappedFloat(InputStream input)
        throws IOException
    {
        return Float.intBitsToFloat( readSwappedInteger( input ) );
    }

    /**
     * Writes a "double" value to an OutputStream. The value is
     * converted to the opposed endian system while writing.
     * @param output target OutputStream
     * @param value value to write
     * @throws IOException in case of an I/O problem
     */
    public static void writeSwappedDouble(OutputStream output, double value)
        throws IOException
    {
        writeSwappedLong( output, Double.doubleToLongBits( value ) );
    }

    /**
     * Reads a "double" value from an InputStream. The value is
     * converted to the opposed endian system while reading.
     * @param input source InputStream
     * @return the value just read
     * @throws IOException in case of an I/O problem
     */
    public static double readSwappedDouble(InputStream input)
        throws IOException
    {
        return Double.longBitsToDouble( readSwappedLong( input ) );
    }

    /**
     * Reads the next byte from the input stream.
     * @param input  the stream
     * @return the byte
     * @throws IOException if the end of file is reached
     */
    private static int read(InputStream input)
        throws IOException
    {
        int value = input.read();

        if( -1 == value ) {
            throw new EOFException( "Unexpected EOF reached" );
        }

        return value;
    }
}