src/test/org/apache/hadoop/chukwa/validationframework/util/MD5.java

package org.apache.hadoop.chukwa.validationframework.util;


import java.io.File;
import java.io.FileInputStream;
import java.io.InputStream;
import java.security.MessageDigest;
import org.apache.hadoop.fs.FSDataInputStream;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;

public class MD5 {
  public static String checksum(File file) {
    try {
      InputStream fin = new FileInputStream(file);
      java.security.MessageDigest md5er = MessageDigest.getInstance("MD5");
      byte[] buffer = new byte[1024];
      int read;
      do {
        read = fin.read(buffer);
        if (read > 0)
          md5er.update(buffer, 0, read);
      } while (read != -1);
      fin.close();
      byte[] digest = md5er.digest();
      if (digest == null)
        return null;
      String strDigest = "0x";
      for (int i = 0; i < digest.length; i++) {
        strDigest += Integer.toString((digest[i] & 0xff) + 0x100, 16)
            .substring(1).toUpperCase();
      }
      return strDigest;
    } catch (Exception e) {
      return null;
    }
  }

  public static String checksum(FileSystem fs, Path file) {
    try {
      FSDataInputStream fin = fs.open(file);
      java.security.MessageDigest md5er = MessageDigest.getInstance("MD5");
      byte[] buffer = new byte[1024];
      int read;
      do {
        read = fin.read(buffer);
        if (read > 0)
          md5er.update(buffer, 0, read);
      } while (read != -1);
      fin.close();
      byte[] digest = md5er.digest();
      if (digest == null)
        return null;
      String strDigest = "0x";
      for (int i = 0; i < digest.length; i++) {
        strDigest += Integer.toString((digest[i] & 0xff) + 0x100, 16)
            .substring(1).toUpperCase();
      }
      return strDigest;
    } catch (Exception e) {
      return null;
    }
  }
}