Android线上轻量级APM性能监测方案

public class LauncherHelpProvider extends ContentProvider {
    // 用来记录启动时间
    public static long sStartUpTimeStamp = SystemClock.uptimeMillis();
    ...
    }

   application.registerActivityLifecycleCallbacks(new Application.ActivityLifecycleCallbacks() {
       @Override
        public void onActivityPaused(@NonNull Activity activity) {
            super.onActivityPaused(activity);
            <!--记录上一个Activity pause节点-->
            mActivityLauncherTimeStamp = SystemClock.uptimeMillis();
            launcherFlag = 0;
        }
        ...
    @Override
    public void onActivityResumed(@NonNull final Activity activity) {
        super.onActivityResumed(activity);
        launcherFlag |= resumeFlag;
       <!--参考上面获取首帧的点-->
             ...

Choreographer.getInstance().postFrameCallback(new Choreographer.FrameCallback() {
    @Override
        public void doFrame(long frameTimeNanos) {
            mFpsCount++;
            mFrameTimeNanos = frameTimeNanos;
            if (isCanWork()) {
                //注册下一帧回调
                Choreographer.getInstance().postFrameCallback(this);
            } else {
                mCurrentCount = 0;
            }
        }
});

      public static void loop() {
                ...
                if (logging != null) {
                    logging.println(">>>>> Dispatching to " + msg.target + " " +
                            msg.callback + ": " + msg.what);
                }
                 ...
                if (logging != null) {
                    logging.println("<<<<< Finished to " + msg.target + " " + msg.callback);
                }

        class LooperPrinter implements Printer {
        @Override
        public void println(String x) {
           ...
            if (isValid) {
            <!--区分开始结束，计算消息耗时-->
                dispatch(x.charAt(0) == '>', x);
        }

    @UnsupportedAppUsage
    public void addCallbackLocked(long dueTime, Object action, Object token) {
        CallbackRecord callback = obtainCallbackLocked(dueTime, action, token);
        CallbackRecord entry = mHead;
        if (entry == null) {
            mHead = callback;
            return;
        }
        if (dueTime < entry.dueTime) {
            callback.next = entry;
            mHead = callback;
            return;
        }
        while (entry.next != null) {
            if (dueTime < entry.next.dueTime) {
                callback.next = entry.next;
                break;
            }
            entry = entry.next;
        }
        entry.next = callback;
    }

private synchronized void addFrameCallback(int type, Runnable callback, boolean isAddHeader) {
    try {
         <!--反射获取方法-->
            addInputQueue = reflectChoreographerMethod(0 “addCallbackLocked”, long.class, Object.class, Object.class);
          <!--添加回调-->
            if (null != method) {
                method.invoke(callbackQueues[type], !isAddHeader ? SystemClock.uptimeMillis() : -1, callback, null);
            }

   application.registerActivityLifecycleCallbacks(new Application.ActivityLifecycleCallbacks() {
        @Override
        public void onActivityDestroyed(@NonNull Activity activity) {
            super.onActivityDestroyed(activity);
            <!--放入map，进行监听-->
            mActivityStringWeakHashMap.put(activity, activity.getClass().getSimpleName());
        }
        @Override
        public void onActivityStopped(@NonNull final Activity activity) {
            super.onActivityStopped(activity);
            //  退后台，GC 找LeakActivity
            if (!ActivityStack.getInstance().isInBackGround()) {
                return;
            }
            Runtime.getRuntime().gc();
            mHandler.postDelayed(new Runnable() {
                @Override
                public void run() {
                    try {
                        if (!ActivityStack.getInstance().isInBackGround()) {
                            return;
                        }
                        try {
                            //   申请个稍微大的对象，促进GC
                            byte[] leakHelpBytes = new byte[4 * 1024 * 1024];
                            for (int i = 0; i < leakHelpBytes.length; i += 1024) {
                                leakHelpBytes[i] = 1;
                            }
                        } catch (Throwable ignored) {
                        }
                        Runtime.getRuntime().gc();
                        SystemClock.sleep(100);
                        System.runFinalization();
                        HashMap<String, Integer> hashMap = new HashMap<>();
                        for (Map.Entry<Activity, String> activityStringEntry : mActivityStringWeakHashMap.entrySet()) {
                            String name = activityStringEntry.getKey().getClass().getName();
                            Integer value = hashMap.get(name);
                            if (value == null) {
                                hashMap.put(name, 1);
                            } else {
                                hashMap.put(name, value + 1);
                            }
                        }
                        if (mMemoryListeners.size() > 0) {
                            for (Map.Entry<String, Integer> entry : hashMap.entrySet()) {
                                for (ITrackMemoryListener listener : mMemoryListeners) {
                                    listener.onLeakActivity(entry.getKey(), entry.getValue());
                                }
                            }
                        }
                    } catch (Exception ignored) {
                    }
                }
            }, 10000);
        }

   application.registerActivityLifecycleCallbacks(new Application.ActivityLifecycleCallbacks() {
        @Override
        public void onActivityStarted(@NonNull Activity activity) {
            super.onActivityStarted(activity);
            <!--开始记录-->
            markActivityStart(activity);
        }
        @Override
        public void onActivityPaused(@NonNull Activity activity) {
            super.onActivityPaused(activity);
            <!--累加-->
            markActivityPause(activity);
        }
        @Override
        public void onActivityDestroyed(@NonNull Activity activity) {
            super.onActivityDestroyed(activity);
            <!--统计结果，并通知回调-->
            markActivityDestroy(activity);
        }
    };