#vulnerable code 
                                @Override
    public Object execute() {
        // Configure command before execution
        introspector.getHystrixProperties()
                    .entrySet()
                    .forEach(entry -> setProperty(entry.getKey(), entry.getValue()));

        // Ensure our internal state is consistent with Hystrix
        if (introspector.hasCircuitBreaker()) {
            breakerHelper.ensureConsistentState();
            LOGGER.info("Enter: breaker for " + getCommandKey() + " in state " + breakerHelper.getState());
        }

        // Record state of breaker
        boolean wasBreakerOpen = isCircuitBreakerOpen();

        // Track invocation in a bulkhead
        if (introspector.hasBulkhead()) {
            bulkheadHelper.trackInvocation(this);
        }

        // Execute command
        Object result = null;
        Throwable throwable = null;
        long startNanos = System.nanoTime();
        try {
            result = super.execute();
        } catch (Throwable t) {
            throwable = t;
        }

        executionTime = System.nanoTime() - startNanos;
        boolean hasFailed = (throwable != null);

        if (introspector.hasCircuitBreaker()) {
            // Keep track of failure ratios
            breakerHelper.pushResult(throwable == null);

            // Query breaker states
            boolean breakerWillOpen = false;
            boolean isClosedNow = !isCircuitBreakerOpen();

            /*
             * Special logic for MP circuit breakers to support failOn. If not a
             * throwable to fail on, restore underlying breaker and return.
             */
            if (hasFailed) {
                final Throwable throwableFinal = throwable;
                Class<? extends Throwable>[] throwableClasses = introspector.getCircuitBreaker().failOn();
                boolean failOn = Arrays.asList(throwableClasses)
                                       .stream()
                                       .anyMatch(c -> c.isAssignableFrom(throwableFinal.getClass()));
                if (!failOn) {
                    restoreBreaker();       // clears Hystrix counters
                    updateMetricsAfter(throwable, wasBreakerOpen, isClosedNow, breakerWillOpen);
                    throw ExceptionUtil.toWrappedException(throwable);
                }
            }

            /*
             * Special logic for MP circuit breakers to support an arbitrary success
             * threshold used to return a breaker back to its CLOSED state. Hystrix
             * only supports a threshold of 1 here, so additional logic is required.
             */
            synchronized (breakerHelper.getSyncObject()) {
                // If failure ratio exceeded, then switch state to OPEN_MP
                if (breakerHelper.getState() == CircuitBreakerHelper.State.CLOSED_MP) {
                    double failureRatio = breakerHelper.getFailureRatio();
                    if (failureRatio >= introspector.getCircuitBreaker().failureRatio()) {
                        breakerWillOpen = true;
                        breakerHelper.setState(CircuitBreakerHelper.State.OPEN_MP);
                        runTripBreaker();
                    }
                }

                // If latest run failed, may need to switch state to OPEN_MP
                if (hasFailed) {
                    if (breakerHelper.getState() == CircuitBreakerHelper.State.HALF_OPEN_MP) {
                        // If failed and in HALF_OPEN_MP, we need to force breaker to open
                        runTripBreaker();
                        breakerHelper.setState(CircuitBreakerHelper.State.OPEN_MP);
                    }
                    updateMetricsAfter(throwable, wasBreakerOpen, isClosedNow, breakerWillOpen);
                    throw ExceptionUtil.toWrappedException(throwable);
                }

                // Check next state of breaker based on outcome
                if (wasBreakerOpen && isClosedNow) {
                    // Last called was successful
                    breakerHelper.incSuccessCount();

                    // We stay in HALF_OPEN_MP until successThreshold is reached
                    if (breakerHelper.getSuccessCount() < introspector.getCircuitBreaker().successThreshold()) {
                        breakerHelper.setState(CircuitBreakerHelper.State.HALF_OPEN_MP);
                    } else {
                        breakerHelper.setState(CircuitBreakerHelper.State.CLOSED_MP);
                        breakerHelper.resetCommandData();
                    }
                }
            }

            updateMetricsAfter(throwable, wasBreakerOpen, isClosedNow, breakerWillOpen);
        }

        // Untrack invocation in a bulkhead
        if (introspector.hasBulkhead()) {
            bulkheadHelper.untrackInvocation(this);
        }

        // Display circuit breaker state at exit
        if (introspector.hasCircuitBreaker()) {
            LOGGER.info("Exit: breaker for " + getCommandKey() + " in state " + breakerHelper.getState());
        }

        // Outcome of execution
        if (throwable != null) {
            throw ExceptionUtil.toWrappedException(throwable);
        } else {
            return result;
        }
    } 
                            #location 37 
                            #vulnerability type THREAD_SAFETY_VIOLATION
#fixed code
                                @Override
    public Object execute() {
        boolean lockRemoved = false;

        try {
            // Configure command before execution
            introspector.getHystrixProperties()
                    .entrySet()
                    .forEach(entry -> setProperty(entry.getKey(), entry.getValue()));

            // Get lock and check breaker delay
            if (introspector.hasCircuitBreaker()) {
                breakerHelper.lock();       // acquire exclusive access to command data

                // OPEN_MP -> HALF_OPEN_MP
                if (breakerHelper.getState() == State.OPEN_MP) {
                    long delayNanos = TimeUtil.convertToNanos(introspector.getCircuitBreaker().delay(),
                            introspector.getCircuitBreaker().delayUnit());
                    if (breakerHelper.getCurrentStateNanos() > delayNanos) {
                        breakerHelper.setState(State.HALF_OPEN_MP);
                    }
                }
                logCircuitBreakerState("Enter");
            }

            // Record state of breaker
            boolean wasBreakerOpen = isCircuitBreakerOpen();

            // Track invocation in a bulkhead
            if (introspector.hasBulkhead()) {
                bulkheadHelper.trackInvocation(this);
            }

            // Execute command
            Object result = null;
            Throwable throwable = null;
            long startNanos = System.nanoTime();
            try {
                result = super.execute();
            } catch (Throwable t) {
                throwable = t;
            }

            executionTime = System.nanoTime() - startNanos;
            boolean hasFailed = (throwable != null);

            if (introspector.hasCircuitBreaker()) {
                // Keep track of failure ratios
                breakerHelper.pushResult(throwable == null);

                // Query breaker states
                boolean breakerOpening = false;
                boolean isClosedNow = !wasBreakerOpen;

                /*
                 * Special logic for MP circuit breakers to support failOn. If not a
                 * throwable to fail on, restore underlying breaker and return.
                 */
                if (hasFailed) {
                    final Throwable throwableFinal = throwable;
                    Class<? extends Throwable>[] throwableClasses = introspector.getCircuitBreaker().failOn();
                    boolean failOn = Arrays.asList(throwableClasses)
                            .stream()
                            .anyMatch(c -> c.isAssignableFrom(throwableFinal.getClass()));
                    if (!failOn) {
                        updateMetricsAfter(throwable, wasBreakerOpen, isClosedNow, breakerOpening);
                        logCircuitBreakerState("Exit 1");
                        throw ExceptionUtil.toWrappedException(throwable);
                    }
                }

                // CLOSED_MP -> OPEN_MP
                if (breakerHelper.getState() == State.CLOSED_MP) {
                    double failureRatio = breakerHelper.getFailureRatio();
                    if (failureRatio >= introspector.getCircuitBreaker().failureRatio()) {
                        breakerHelper.setState(State.OPEN_MP);
                        breakerOpening = true;
                    }
                }

                // HALF_OPEN_MP -> OPEN_MP
                if (hasFailed) {
                    if (breakerHelper.getState() == State.HALF_OPEN_MP) {
                        breakerHelper.setState(State.OPEN_MP);
                    }
                    updateMetricsAfter(throwable, wasBreakerOpen, isClosedNow, breakerOpening);
                    logCircuitBreakerState("Exit 2");
                    throw ExceptionUtil.toWrappedException(throwable);
                }

                // Otherwise, increment success count
                breakerHelper.incSuccessCount();

                // HALF_OPEN_MP -> CLOSED_MP
                if (breakerHelper.getState() == State.HALF_OPEN_MP) {
                    if (breakerHelper.getSuccessCount() == introspector.getCircuitBreaker().successThreshold()) {
                        breakerHelper.setState(State.CLOSED_MP);
                        breakerHelper.resetCommandData();
                        lockRemoved = true;
                        isClosedNow = true;
                    }
                }

                updateMetricsAfter(throwable, wasBreakerOpen, isClosedNow, breakerOpening);
            }

            // Untrack invocation in a bulkhead
            if (introspector.hasBulkhead()) {
                bulkheadHelper.untrackInvocation(this);
            }

            // Display circuit breaker state at exit
            logCircuitBreakerState("Exit 3");

            // Outcome of execution
            if (throwable != null) {
                throw ExceptionUtil.toWrappedException(throwable);
            } else {
                return result;
            }
        } finally {
            // Free lock unless command data was reset
            if (introspector.hasCircuitBreaker() && !lockRemoved) {
                breakerHelper.unlock();
            }
        }
    }