Method doBackground

xutils/src/main/java/org/xutils/http/HttpTask.java:181–366

()

    }

    @Override
    @SuppressWarnings("unchecked")
    protected ResultType doBackground() throws Throwable {

        if (this.isCancelled()) {
            throw new Callback.CancelledException("cancelled before request");
        }

        // 初始化请求参数
        ResultType result = null;
        resolveLoadType();
        request = createNewRequest();
        checkDownloadTask();
        // retry 初始化
        boolean retry = true;
        int retryCount = 0;
        Throwable exception = null;
        HttpRetryHandler retryHandler = this.params.getHttpRetryHandler();
        if (retryHandler == null) {
            retryHandler = new HttpRetryHandler();
        }
        retryHandler.setMaxRetryCount(this.params.getMaxRetryCount());

        if (this.isCancelled()) {
            throw new Callback.CancelledException("cancelled before request");
        }

        // 检查缓存
        Object cacheResult = null;
        if (cacheCallback != null && HttpMethod.permitsCache(params.getMethod())) {
            // 尝试从缓存获取结果, 并为请求头加入缓存控制参数.
            try {
                clearRawResult();
                LogUtil.d("load cache: " + this.request.getRequestUri());
                rawResult = this.request.loadResultFromCache();
            } catch (Throwable ex) {
                LogUtil.w("load disk cache error", ex);
            }

            if (this.isCancelled()) {
                clearRawResult();
                throw new Callback.CancelledException("cancelled before request");
            }

            if (rawResult != null) {
                if (prepareCallback != null) {
                    try {
                        cacheResult = prepareCallback.prepare(rawResult);
                    } catch (Throwable ex) {
                        cacheResult = null;
                        LogUtil.w("prepare disk cache error", ex);
                    } finally {
                        clearRawResult();
                    }
                } else {
                    cacheResult = rawResult;
                }