获取应用启动时间

BootTime.java

// 应用启动时间
private long getStartTime() throws Exception {
        if (Build.VERSION.SDK_INT >= 24) {
            return Process.getStartElapsedRealtime();
        }
        final String path = "/proc/" + Process.myPid() + "/stat";
        final BufferedReader reader = new BufferedReader(new FileReader(path));
        final String stat;
        try {
            stat = reader.readLine();
        } finally {
            reader.close();
        }
        final String field2End = ") ";
        final String fieldSep = " ";
        final int fieldStartTime = 20;
        final int msInSec = 1000;
        final String[] fields = stat.substring(stat.lastIndexOf(field2End)).split(fieldSep);
        final long t = Long.parseLong(fields[fieldStartTime]);
        int tckName;
        try {
            tckName = Class.forName("android.system.OsConstants").getField("_SC_CLK_TCK").getInt(null);
        } catch (ClassNotFoundException e) {
            tckName = Class.forName("libcore.io.OsConstants").getField("_SC_CLK_TCK").getInt(null);
        }
        final Object os = Class.forName("libcore.io.Libcore").getField("os").get(null);
        final long tck = (Long) os.getClass().getMethod("sysconf", Integer.TYPE).invoke(os, tckName);
        return t * msInSec / tck;
    }

// 应用已启动总时长(ms)
long bootTime = (SystemClock.elapsedRealtime() - startTime) / 1000);