（N）Telephony分析（六）之DcTracker的requestNetwork分析

最新推荐文章于 2023-08-22 16:24:51 发布

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最新推荐文章于 2023-08-22 16:24:51 发布 · 2k 阅读

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CC 4.0 BY-SA版权

本文深入探讨了PhoneApp初始化过程中，TelephonyNetworkFactory如何调用DcTracker的requestNetwork方法，接着分析了ApnContext请求网络的过程，以及DcTracker的setEnabled和trySetupData方法的逻辑。在当前流程中，数据连接并未成功建立，文章预告将分析数据连接的实际建立流程。

在PhoneApp的初始化中，我们分析到，TelephonyNetworkFactory的初始化，最终会调用到DcTracker的requestNetwork方法

private void onNeedNetworkFor(Message msg) {
    NetworkRequest networkRequest = (NetworkRequest)msg.obj;
    boolean isApplicable = false;
    LocalLog localLog = null;
    if (TextUtils.isEmpty(networkRequest.networkCapabilities.getNetworkSpecifier())) {
        // request only for the default network
        localLog = mDefaultRequests.get(networkRequest);
        if (localLog == null) {
            localLog = new LocalLog(REQUEST_LOG_SIZE);
            localLog.log("created for " + networkRequest);
            mDefaultRequests.put(networkRequest, localLog);
            isApplicable = mIsDefault;
        }
    } else {
        localLog = mSpecificRequests.get(networkRequest);
        if (localLog == null) {
            localLog = new LocalLog(REQUEST_LOG_SIZE);
            mSpecificRequests.put(networkRequest, localLog);
            isApplicable = true;
        }
    }
    if (mIsActive && isApplicable) {
        String s = "onNeedNetworkFor";
        localLog.log(s);
        log(s + " " + networkRequest);
        mDcTracker.requestNetwork(networkRequest, localLog);
    } else {
        String s = "not acting - isApp=" + isApplicable + ", isAct=" + mIsActive;
        localLog.log(s);
        log(s + " " + networkRequest);
    }
}

而DcTracker的requestNetwork方法主要有

public void requestNetwork(NetworkRequest networkRequest, LocalLog log) {
    final int apnId = ApnContext.apnIdForNetworkRequest(networkRequest);
    final ApnContext apnContext = mApnContextsById.get(apnId);
    log.log("DcTracker.requestNetwork for " + networkRequest + " found " + apnContext);
    if (apnContext != null) apnContext.requestNetwork(networkRequest, log);
}

从前面DcTracker的初始化文章中，我们知道此处apnId为DctConstants.APN_DEFAULT_ID，那么ApnContext所对应的数据为

public ApnContext(Phone phone, String apnType, String logTag, NetworkConfig config,
        DcTracker tracker) {
    mPhone = phone;
    mApnType = apnType;
    mState = DctConstants.State.IDLE;
    setReason(Phone.REASON_DATA_ENABLED);
    mDataEnabled = new AtomicBoolean(false);
    mDependencyMet = new AtomicBoolean(config.dependencyMet);
    priority = config.priority;
    LOG_TAG = logTag;
    mDcTracker = tracker;
    mRetryManager = new RetryManager(phone, apnType);
}

即apnType为default，priority为0,mDependencyMet为true

接下来，是调用了ApnContext的requestNetwork方法

public void requestNetwork(NetworkRequest networkRequest, LocalLog log) {
    synchronized (mRefCountLock) {
        if (mLocalLogs.contains(log) || mNetworkRequests.contains(networkRequest)) {
            log.log("ApnContext.requestNetwork has duplicate add - " + mNetworkRequests.size());
        } else {
            mLocalLogs.add(log);
            mNetworkRequests.add(networkRequest);
            mDcTracker.setEnabled(apnIdForApnName(mApnType), true);
        }
    }
}

此方法主要是将当前的networkRequest加入到mNetworkRequests中进行管理，然后调用了DcTracker的setEnabled