(Java) BCrypt Verify a Password (Check if Password is Correct)

A system that uses BCrypt for storing passwords would not store the actual password, but would instead store the bcrypt hash of the password. When a user presents the password, such as for login, call BCryptVerify to verify the password against the stored bcrypt hash.

Note: This example requires Chilkat v9.5.0.65 or greater.

Chilkat Java Downloads Java Libs for Windows, MacOS, Linux, Alpine Linux, Solaris Java Libs for Android

import com.chilkatsoft.*;

public class ChilkatExample {

  static {
    try {
        System.loadLibrary("chilkat");
    } catch (UnsatisfiedLinkError e) {
      System.err.println("Native code library failed to load.\n" + e);
      System.exit(1);
    }
  }

  public static void main(String argv[])
  {
    // This example assumes the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    CkCrypt2 crypt = new CkCrypt2();

    String storedHash = "$2a$10$H5kIVktMGzAPKGKNAe9DVu0iwEqfhv/o4MMJ/Dzw/MPy1leOE9NOK";
    String password = "mySecretPassword";

    boolean passwordValid = crypt.BCryptVerify(password,storedHash);
    if (passwordValid == true) {
        System.out.println(password + " is valid.");
        }
    else {
        System.out.println(password + " is NOT valid.");
        }

    password = "notAValidPassword";
    passwordValid = crypt.BCryptVerify(password,storedHash);
    if (passwordValid == true) {
        System.out.println(password + " is valid.");
        }
    else {
        System.out.println(password + " is NOT valid.");
        }

    // Output should be:

    // 	mySecretPassword is valid.
    // 	notAValidPassword is NOT valid.
  }
}