* from memory.
     *
     * @return the password as a char array
     */
    public char[] getPasswordAsCharArray() {
        checkNotClosed();
        return this.password != null && this.password.length > 0 ? this.password.clone() : this.password == null ? null : new char[0];
    }

    /**
     * Securely wipes the password from memory
     */

        }
        return redirect(getClass());
    }

    /**
     * Handles password change for the current user.
     *
     * @param form the password form containing new password and confirmation
     * @return the HTML response after password change attempt
     */
    @Execute
    public HtmlResponse changePassword(final PasswordForm form) {

* The **input model** needs to be able to have a password.
* The **output model** should not have a password.
* The **database model** would probably need to have a hashed password.

/// danger

Never store user's plaintext passwords. Always store a "secure hash" that you can then verify.

If you don't know, you will learn what a "password hash" is in the [security chapters](security/simple-oauth2.md#password-hashing){.internal-link target=_blank}.

///

    }

    /**
     * Changes the password for a user across all authentication chains.
     * @param username The username for which to change the password.
     * @param password The new password.
     * @return True if the password was successfully changed in all chains, false otherwise.
     */
    public boolean changePassword(final String username, final String password) {

/**
 * Form for password change.
 */
public class PasswordForm {

    /**
     * Default constructor.
     */
    public PasswordForm() {
        // Default constructor
    }

    /** The username. */
    public String username;

    /** The password. */
    @NotBlank
    public String password;

    /** The confirm password. */
    @NotBlank

    /**
     * Creates a new LocalUserCredential with the specified user and password.
     *
     * @param user the username
     * @param password the password
     */
    public LocalUserCredential(final String user, final String password) {
        super(user, password);
    }

    @Override
    public String getUserId() {
        return getUser();
    }

            credentials = new NTCredentials(username, password == null ? StringUtil.EMPTY : password,
                    workstation == null ? StringUtil.EMPTY : workstation, domain == null ? StringUtil.EMPTY : domain);
        } else {
            credentials = new UsernamePasswordCredentials(username, password == null ? StringUtil.EMPTY : password);
        }
        return credentials;
    }

        return hmac.digest();
    }

    /**
     * Generates the NT password hash for the given password.
     *
     * @param password the password to hash
     * @return nt password hash
     */
    public static byte[] getNTHash(final String password) {
        if (password == null) {
            throw new NullPointerException("Password parameter is required");
        }

            auth1.close();
            auth2.close();
        }
    }

    /**
     * Test concurrent password comparisons to ensure thread safety and consistent timing.
     */
    @Test
    public void testConcurrentTimingConsistency() throws Exception {
        final char[] password = "concurrenttestpassword".toCharArray();
        final char[] wrongPassword = "concurrenttestpassworX".toCharArray(); // Different at end

# Simple OAuth2 with Password and Bearer { #simple-oauth2-with-password-and-bearer }

Now let's build from the previous chapter and add the missing parts to have a complete security flow.

## Get the `username` and `password` { #get-the-username-and-password }

We are going to use **FastAPI** security utilities to get the `username` and `password`.