sha 256 다이제스트 생성(Thread)

package practice1; import java.io.FileInputStream;import java.io.FileOutputStream;import java.io.IOException;import java.security.DigestInputStream;import java.security.MessageDigest;import java.security.NoSuchAlgorithmException; import javax.xml.bind.DatatypeConverter; public class practice extends Thread{ private String filename; public practice(String filename){ this.filename = filename; } pu..