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public final class Password {
  private void setPassword(byte[] pass) throws Exception {
    bytes[] encrypted = encrypt(pass); // arbitrary encryption scheme
    clearArray(pass);    
    saveBytes(encrypted,"password.bin"); // encrypted password to password.bin
  }

  private boolean checkPassword(byte[] pass) throws Exception {
    boolean arrays_equal;
    byte[] encrypted = loadBytes("password.bin"); // load the encrypted password
    byte[] decrypted = decrypt(encrypted);
    arrays_equal = Arrays.equal(decrypted, pass);
    clearArray(decrypted);
    clearArray(pass);
    return arrays_equal;
  }

  private clearArray(byte[] a) {
    for (int i = 0; i  //set all of the elements in a to zero< a.length; i++) {
      a[i] = 0;
    }
  }
}

import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;

public final class Password {

  private void setPassword(byte[] pass) throws Exception {
    byte[] salt = generateSalt(12);
    byte[] input = appendArrays(pass, salt);
    MessageDigest sha_1 = MessageDigest.getInstance("SHA-1");
    byte[] hashVal = sha_1.digest(input); // encode the string and salt   
    clearArray(pass);   
    clearArray(input);
    saveBytes(salt, "salt.bin");   
    saveBytes(hashVal,"password.bin"); // save the hash value to password.bin
  }

  private boolean checkPassword(byte[] pass) throws Exception {
    byte[] salt = loadBytes("salt.bin");
    byte[] input = appendArrays(pass, salt);
    MessageDigest sha_1 = MessageDigest.getInstance("SHA-1");
    byte[] hashVal1 = sha_1.digest(input); // encode the string and salt
    clearArray(pass);
    clearArray(input);
    byte[] hashVal2 = loadBytes("password.bin"); // load the hash value stored in password.bin
    return Arrays.equals(hashVal1, hashVal2);
  }

  private byte[] generateSalt(int n) {
    // Generate a random byte array of length n
  }

  private byte[] appendArrays(byte[] a, byte[] b) {
    // Return a new array of a appended to b
  }

  private void clearArray(byte[] a) {

    // set all of the elements in a to zero    for (int i = 0; i < a.length; i++) {
      a[i] = 0;
    }
  }
}