Invert the endianness of words (4 bytes) in the given byte array starting at the given offset and repeating length/4 times.

 
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/**
 * ByteUtilities.java - Byte manipulation functions.
 * 
 * @author <a href="http://mina.apache.org">Apache MINA Project</a>
 * @since MINA 2.0.0-M3
 */
public class Util{


    /**
     * Invert the endianness of words (4 bytes) in the given byte array 
     * starting at the given offset and repeating length/4 times.
     * eg: b0b1b2b3 -> b3b2b1b0 
     * 
     * @param b the byte array 
     * @param offset the offset at which to change word start
     * @param length the number of bytes on which to operate 
     * (should be a multiple of 4)
     */
    public final static void changeWordEndianess(byte[] b, int offset,
            int length) {
        byte tmp;

        for (int i = offset; i < offset + length; i += 4) {
            tmp = b[i];
            b[i] = b[i + 3];
            b[i + 3] = tmp;
            tmp = b[i + 1];
            b[i + 1] = b[i + 2];
            b[i + 2] = tmp;
        }
    }

    /**
     * Invert two bytes in the given byte array starting at the given 
     * offset and repeating the inversion length/2 times.
     * eg: b0b1 -> b1b0
     * 
     * @param b the byte array 
     * @param offset the offset at which to change word start
     * @param length the number of bytes on which to operate 
     * (should be a multiple of 2)
     */
    public final static void changeByteEndianess(byte[] b, int offset,
            int length) {
        byte tmp;

        for (int i = offset; i < offset + length; i += 2) {
            tmp = b[i];
            b[i] = b[i + 1];
            b[i + 1] = tmp;
        }
    }


}

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Invert the endianness of words (4 bytes) in the given byte array starting at the given offset and repeating length/4 times. : Byte Array « File Input Output « Java

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