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I am trying to make same result with Java in the javascript using CryptoJs. But I am failed many times. I found the CryptoJs to generate Hash value in the javascript recently . But It was defficult to make same result between javascript and java. I want to get hash value (checksum) from zip or xls ,doc . And the Java application have to check if it has same hash value or not. Does anyone know whats going wrong on my javascript?

====== java source ==========

public static String getFileHashSHA256(String fileName) throws Exception {

    int buff = 16384;

    RandomAccessFile file = new RandomAccessFile(fileName, "r");
    MessageDigest hashSum = MessageDigest.getInstance("SHA-256");

    byte[] buffer = new byte[buff];
    byte[] partialHash = null;

    long read = 0;

    long offset = file.length();
    int unitsize;

    while (read < offset) {

        unitsize = (int) (((offset - read) >= buff) ? buff : (offset - read));
        file.read(buffer, 0, unitsize);

        hashSum.update(buffer, 0, unitsize);

        read += unitsize;
    }
    file.close();

    partialHash = new byte[hashSum.getDigestLength()];
    partialHash = hashSum.digest();

    StringBuffer sb = new StringBuffer();
    for (int i = 0; i < partialHash.length; i++) {
        sb.append(Integer.toString((partialHash[i] & 0xff) + 0x100, 16).substring(1));
    }

    return sb.toString();

}

result hash value : 2f3512d3caad7b43f0036bafa7c80e78e9fca6a253857d24b1c38dc5cdab1399

========= javascript source ==============

var fileToLoad = document.getElementById("fileToLoad").files[0];

var fileReader = new FileReader();
fileReader.readAsBinaryString(fileToLoad);
fileReader.onload = function(fileLoadedEvent) 
{

    var hash = CryptoJS.SHA256(fileLoadedEvent.target.result).toString();
    console.log(hash);

};

result hash value : cc7cf3ed59fb26a43d2596e54c48bced09ad22bff68e2cb5a1ea7cc80b48387d

The both hash value is diffrent even though it bring from a same zip file.

spaceking7
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  • Do the answers on [this question](http://stackoverflow.com/q/13981832/1816580) help? – Artjom B. Mar 25 '16 at 09:38
  • [Here](http://stackoverflow.com/a/33918579/1816580) is a correct way to do it in CryptoJS. Try it. I'm not going to close it as duplicate for now, because your Java code looks rather strange. You don't need `unitsize`. Instead you should use the return value of `file.read()`. – Artjom B. Mar 25 '16 at 09:47
  • thanks for your reply. but i can't change java source because it has used for many years. Our DB has the file hash information already. therefore i want to change only the javascript . Is it possible? – spaceking7 Mar 27 '16 at 23:58
  • Yes, I've run your Java code and checked if it produces the same result as my answer in the duplicate link. – Artjom B. Mar 28 '16 at 00:22
  • Thanks a lot for your help. I took a test for your code in my local And I found it bring same result with Java code. It was very helpful for me. Thanks again. – spaceking7 Mar 31 '16 at 04:18

0 Answers0