CRC32HashBuilder.java Source code

Introduction

Here is the source code for CRC32HashBuilder.java

Source

import java.io.IOException;
import java.io.InputStream;
import java.math.BigInteger;
import java.util.zip.CRC32;
import java.util.zip.Checksum;

/**
 * Uses CRC32 algorithm for creating fingerprint.
 * 
 * @author Alex Objelean
 */
public class CRC32HashBuilder {

    /**
     * {@inheritDoc}
     */
    public String getHash(final InputStream input) throws IOException {
        if (input == null) {
            throw new IllegalArgumentException("Content cannot be null!");
        }
        final Checksum checksum = new CRC32();
        final byte[] bytes = new byte[1024];
        int len = 0;
        while ((len = input.read(bytes)) >= 0) {
            checksum.update(bytes, 0, len);
        }

        final String hash = new BigInteger(Long.toString(checksum.getValue())).toString(16);
        return hash;
    }
}