How to convert a Byte Array to an Int Array

Question

I am reading a file by using:

int len = (int)(new File(args[0]).length());
    FileInputStream fis =
        new FileInputStream(args[0]);
    byte buf[] = n         


        

Answer 1

Solution for converting an array of bytes into an array of integers, where each set of 4 bytes represents an integer. The byte input is byte[] srcByte. The int output is dstInt[].

Little-endian source bytes:

    int shiftBits;
    int byteNum = 0;
    int[] dstInt = new int[srcByte.length/4]; //you might have to hard code the array length

    //Convert array of source bytes (srcByte) into array of integers (dstInt)
    for (int intNum = 0; intNum < srcByte.length/4; ++intNum) {  //for the four integers
        dstInt[intNum] = 0;                                      //Start with the integer = 0

        for(shiftBits = 0; shiftBits < 32; shiftBits += 8) {     //Add in each data byte, lowest first
            dstInt[intNum] |= (srcByte[byteNum++] & 0xFF) << shiftBits;
        }
    }

For Big-Endian substitute this line:

    for(shiftBits = 24; shiftBits >= 0; shiftBits -= 8)  //Add in each data byte, highest first