Java CRC Calculate computeCrc32(InputStream is)

Here you can find the source of computeCrc32(InputStream is)

Description

Compute the CRC-32 of the contents of a stream.

License

Open Source License

Declaration

static String computeCrc32(InputStream is) throws IOException 

Method Source Code

//package com.java2s;
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import java.io.IOException;
import java.io.InputStream;

import java.util.zip.CRC32;
import java.util.zip.Checksum;

public class Main {
    /**
     * Compute the CRC-32 of the contents of a stream.
     * \r\n and \r are both normalized to \n for purposes of the calculation.
     */
    static String computeCrc32(InputStream is) throws IOException {
        Checksum crc = new CRC32();
        int last = -1;
        int curr;
        while ((curr = is.read()) != -1) {
            if (curr != '\n' && last == '\r') {
                crc.update('\n');
            }
            if (curr != '\r') {
                crc.update(curr);
            }
            last = curr;
        }
        if (last == '\r') {
            crc.update('\n');
        }
        int val = (int) crc.getValue();
        String hex = Integer.toHexString(val);
        while (hex.length() < 8) {
            hex = "0" + hex; // NOI18N
        }
        return hex;
    }
}

Related

  1. calculateCRC(String id)
  2. calculateCrc16(byte[] buffer)
  3. calculateCRC32(byte[] buf, int off, int len)
  4. computeCRC(InputStream in)
  5. computeCRC32(File file)
  6. CRC(String message)
  7. crc16(byte[] bytes)
  8. crc16(final byte[] bytes)
  9. crc16_get(byte aby[], int nOffset, int nLength)