#vulnerable code 
                                protected ClientConnectionManager createClientConnectionManager() {
        SchemeRegistry registry = SchemeRegistryFactory.createDefault();

        ClientConnectionManager connManager = null;
        HttpParams params = getParams();

        ClientConnectionManagerFactory factory = null;

        String className = (String) params.getParameter(
                ClientPNames.CONNECTION_MANAGER_FACTORY_CLASS_NAME);
        if (className != null) {
            try {
                Class<?> clazz = Class.forName(className);
                factory = (ClientConnectionManagerFactory) clazz.newInstance();
            } catch (ClassNotFoundException ex) {
                throw new IllegalStateException("Invalid class name: " + className);
            } catch (IllegalAccessException ex) {
                throw new IllegalAccessError(ex.getMessage());
            } catch (InstantiationException ex) {
                throw new InstantiationError(ex.getMessage());
            }
        }
        if (factory != null) {
            connManager = factory.newInstance(params, registry);
        } else {
            connManager = new SingleClientConnManager(registry);
        }

        return connManager;
    } 
                            #location 26 
                            #vulnerability type INTERFACE_NOT_THREAD_SAFE
#fixed code
                                protected ClientConnectionManager createClientConnectionManager() {
        SchemeRegistry registry = SchemeRegistryFactory.createDefault();

        ClientConnectionManager connManager = null;
        HttpParams params = getParams();

        ClientConnectionManagerFactory factory = null;

        String className = (String) params.getParameter(
                ClientPNames.CONNECTION_MANAGER_FACTORY_CLASS_NAME);
        if (className != null) {
            try {
                Class<?> clazz = Class.forName(className);
                factory = (ClientConnectionManagerFactory) clazz.newInstance();
            } catch (ClassNotFoundException ex) {
                throw new IllegalStateException("Invalid class name: " + className);
            } catch (IllegalAccessException ex) {
                throw new IllegalAccessError(ex.getMessage());
            } catch (InstantiationException ex) {
                throw new InstantiationError(ex.getMessage());
            }
        }
        if (factory != null) {
            connManager = factory.newInstance(params, registry);
        } else {
            connManager = new PoolingClientConnectionManager(registry);
        }

        return connManager;
    }