AsyncTask异步转同步

项目背景：指纹支付中获取IFAA设备ID，部分厂商系统升级之后会出现获取ID超时现象，在没做判空处理的情况下产品会全线崩溃。

方案：在项目启动的时候进行IFAA初始化。

/**
 * 初始化ifaaDeviceId,存入缓存
 *
 * @param typeFingerprint
 */
public static void initIfaaDeviceIdByType(int typeFingerprint) {
	long startTime = System.currentTimeMillis();
	LogUtils.d(TAG, "initIfaaDeviceIdByType start type:" + typeFingerprint);

	if (authenticator == null) {
		authenticator = AuthenticatorManager.create(PayKernelApplication.getInstance(), typeFingerprint, appName);
	}
	//底层抛null
	if (authenticator == null) {
		ifaaDeviceId = "";
		isSupportIfaaDeviceId = false;
		sendIfaaNetLog(startTime, "创建authenticator失败");
		return;
	}

	if (!authenticator.isSupported()
			|| !authenticator.hasEnrolled()) {
		ifaaDeviceId = "";
		isSupportIfaaDeviceId = false;
		sendIfaaNetLog(startTime, "不支持IFAA");
		return;
	}

	String log = "";
	executor = (Executor) Executors.newCachedThreadPool();
	mTask = new IfaaSdkDeviceIdTask(authenticator);
	try {
		mTask.executeOnExecutor(executor);
		ifaaDeviceId = mTask.get(TIME_OUT, TimeUnit.MILLISECONDS);
		if (TextUtils.isEmpty(ifaaDeviceId)) {
			isSupportIfaaDeviceId = false;
			log = "initIfaaDeviceIdByType调取失败ifaaDeviceId为空" + ifaaDeviceId;
		} else {
			isSupportIfaaDeviceId = true;
			log = "initIfaaDeviceIdByType调取成功ifaaDeviceId：" + ifaaDeviceId;
		}
	} catch (InterruptedException e) {
		ifaaDeviceId = "";
		isSupportIfaaDeviceId = false;
		log = "initIfaaDeviceIdByType调取InterruptedException";
		authenticator.cancel();
	} catch (ExecutionException e) {
		ifaaDeviceId = "";
		isSupportIfaaDeviceId = false;
		log = "initIfaaDeviceIdByType调取ExecutionException";
		authenticator.cancel();
	} catch (TimeoutException e) {
		ifaaDeviceId = "";
		isSupportIfaaDeviceId = false;
		log = "initIfaaDeviceIdByType调取超时";
		authenticator.cancel();
	}
	LogUtils.d(TAG, log); 
}

public class IfaaSdkDeviceIdTask extends AsyncTask {

    private IAuthenticator mIAuthenticator;

    public IfaaSdkDeviceIdTask(IAuthenticator iAuthenticator) {
        this.mIAuthenticator = iAuthenticator;
    }

    @Override
    protected String doInBackground(Void... params) {
        String deviceId = null;
        if (mIAuthenticator != null) {
            //获取ifaa的DeviceId 
            deviceId = mIAuthenticator.getDeviceId();
        }

        //返回DeviceId
        return deviceId;
    }

    @Override
    protected void onPostExecute(String result) {
    }
}

细节：mTask.get()方法是超时判断方法，如果在规定时间异步线程没有完成的情况下直接会有超时异常，但是原有的线程会继续运行，所以需要在超时处理中中断获取deviceId的操作，mTask.get()获取的结果就是doInBackground返回的结果，所以onPostExecute中不需要再次对结果进行处理，否则会出现二次处理的逻辑混乱。