- import java.util.zip.CheckedInputStream;
- import java.util.zip.CRC32;
- import java.io.File;
- import java.io.FileInputStream;
- import java.io.FileNotFoundException;
- import java.io.IOException;
- /**
- * -----------------------------------------------------------------------------
- * Used to provide an example of how to calculate the checksum of a file using
- * the CRC-32 checksum engine.
- *
- * @version 1.0
- * @author Jeffrey M. Hunter (jhunter@idevelopment.info)
- * @author <a href="http://www.idevelopment.info">http://www.idevelopment.info
- * -----------------------------------------------------------------------------
- */
- public class ChecksumCRC32 {
- private static void doChecksum(String fileName) {
- try {
- CheckedInputStream cis = null;
- long fileSize = 0;
- try {
- // Computer CRC32 checksum
- cis = new CheckedInputStream(
- new FileInputStream(fileName), new CRC32());
- fileSize = new File(fileName).length();
- } catch (FileNotFoundException e) {
- System.err.println("File not found.");
- System.exit(1);
- }
- byte[] buf = new byte[128];
- while(cis.read(buf) >= 0) {
- }
- long checksum = cis.getChecksum().getValue();
- System.out.println(checksum + " " + fileSize + " " + fileName);
- } catch (IOException e) {
- e.printStackTrace();
- System.exit(1);
- }
- }
- /**
- * Sole entry point to the class and application.
- * @param args Array of String arguments.
- */
- public static void main(String[] args) {
- if (args.length != 1) {
- System.err.println("Usage: java ChecksumCRC32 filename");
- } else {
- doChecksum(args[0]);
- }
- }
- }
- //该片段来自于http://www.codesnippet.cn/detail/03122012781.html
来源: http://www.codesnippet.cn/detail/03122012781.html