import java.io.IOException;

/**
 * Abstract base class for SPNEGO authentication tokens used in GSS-API negotiation
 */
public abstract class SpnegoToken {

    /**
     * Protected constructor for SPNEGO token implementations.
     */
    protected SpnegoToken() {
    }

    private byte[] mechanismToken;

    private byte[] mechanismListMIC;

    /**

/**
 * Tests for SpnegoToken.
 * Uses a minimal concrete subclass to exercise abstract methods.
 */
class SpnegoTokenTest {

    /**
     * Minimal concrete implementation for testing.
     * - parse: sets mechanismToken, throws on null
     * - toByteArray: returns mechanismToken or empty array if null
     */
    static class TestSpnegoToken extends SpnegoToken {
        private boolean parsed = false;

import org.bouncycastle.asn1.DERSequence;
import org.bouncycastle.asn1.DERTaggedObject;

/**
 * SPNEGO response token (NegTokenTarg) used in SPNEGO authentication exchanges
 */
public class NegTokenTarg extends SpnegoToken {

    /**
     * Result code indicating unspecified result
     */
    public static final int UNSPECIFIED_RESULT = -1;
    /**
     * Result code indicating authentication completed successfully
     */