Android获取设备CPU核数、时钟频率以及内存大小的方法

root@generic_x86_64:/sys/devices/system/cpu # lscpu0cpufreqcpuidlekernel_maxmodaliasofflineonlinepossiblepowerpresentuevent

public static int getNumberOfCPUCores() { if (Build.VERSION.SDK_INT <= Build.VERSION_CODES.GINGERBREAD_MR1) { // Gingerbread doesn't support giving a single application access to both cores, but a // handful of devices (Atrix 4G and Droid X2 for example) were released with a dual-core // chipset and Gingerbread; that can let an app in the background run without impacting // the foreground application. But for our purposes, it makes them single core. return 1; } int cores; try { cores = new File("/sys/devices/system/cpu/").listFiles(CPU_FILTER).length; } catch (SecurityException e) { cores = DEVICEINFO_UNKNOWN; } catch (NullPointerException e) { cores = DEVICEINFO_UNKNOWN; } return cores;}private static final FileFilter CPU_FILTER = new FileFilter() { @Override public boolean accept(File pathname) { String path = pathname.getName(); //regex is slow, so checking char by char. if (path.startsWith("cpu")) {  for (int i = 3; i < path.length(); i++) {  if (path.charAt(i) < '0' || path.charAt(i) > '9') {   return false;  }  }  return true; } return false; }};

public static int getCPUMaxFreqKHz() { int maxFreq = DEVICEINFO_UNKNOWN; try { for (int i = 0; i < getNumberOfCPUCores(); i++) {  String filename =   "/sys/devices/system/cpu/cpu" + i + "/cpufreq/cpuinfo_max_freq";  File cpuInfoMaxFreqFile = new File(filename);  if (cpuInfoMaxFreqFile.exists()) {  byte[] buffer = new byte[128];  FileInputStream stream = new FileInputStream(cpuInfoMaxFreqFile);  try {   stream.read(buffer);   int endIndex = 0;   //Trim the first number out of the byte buffer.   while (buffer[endIndex] >= '0' && buffer[endIndex] <= '9'    && endIndex < buffer.length) endIndex++;   String str = new String(buffer, 0, endIndex);   Integer freqBound = Integer.parseInt(str);   if (freqBound > maxFreq) maxFreq = freqBound;  } catch (NumberFormatException e) {   //Fall through and use /proc/cpuinfo.  } finally {   stream.close();  }  } } if (maxFreq == DEVICEINFO_UNKNOWN) {  FileInputStream stream = new FileInputStream("/proc/cpuinfo");  try {  int freqBound = parseFileForValue("cpu MHz", stream);  freqBound *= 1000; //MHz -> kHz  if (freqBound > maxFreq) maxFreq = freqBound;  } finally {  stream.close();  } } } catch (IOException e) { maxFreq = DEVICEINFO_UNKNOWN; //Fall through and return unknown. } return maxFreq;}

ActivityManager.MemoryInfo memInfo = new ActivityManager.MemoryInfo();ActivityManager am = (ActivityManager) c.getSystemService(Context.ACTIVITY_SERVICE);am.getMemoryInfo(memInfo);

FileInputStream stream = new FileInputStream("/proc/meminfo");totalMem = parseFileForValue("MemTotal", stream);

@TargetApi(Build.VERSION_CODES.JELLY_BEAN)public static long getTotalMemory(Context c) { // memInfo.totalMem not supported in pre-Jelly Bean APIs. if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN) { ActivityManager.MemoryInfo memInfo = new ActivityManager.MemoryInfo(); ActivityManager am = (ActivityManager) c.getSystemService(Context.ACTIVITY_SERVICE); am.getMemoryInfo(memInfo); if (memInfo != null) {  return memInfo.totalMem; } else {  return DEVICEINFO_UNKNOWN; } } else { long totalMem = DEVICEINFO_UNKNOWN; try {  FileInputStream stream = new FileInputStream("/proc/meminfo");  try {  totalMem = parseFileForValue("MemTotal", stream);  totalMem *= 1024;  } finally {  stream.close();  } } catch (IOException e) { } return totalMem; }}