读取 cpu百分比 进程占用cpu百分比的JAVA实现方式_java 获取设备cpu百分比

话不多说直接上代码：讲述两种CPU

TotalCpuTime

<span style="font-size:14px;">private static long getTotalCpuTime() { // 获取系统总CPU使用时间
String[] cpuInfos = null;
try {
BufferedReader reader = new BufferedReader(new InputStreamReader(
new FileInputStream("/proc/stat")), 1000);
String load = reader.readLine();
reader.close();
cpuInfos = load.split(" ");
// System.out.println("cpulist:"+Arrays.toString(cpuInfos));
} catch (IOException ex) {
ex.printStackTrace();
}
long totalCpu = Long.parseLong(cpuInfos[2])
+ Long.parseLong(cpuInfos[3]) + Long.parseLong(cpuInfos[4])
+ Long.parseLong(cpuInfos[6]) + Long.parseLong(cpuInfos[5])
+ Long.parseLong(cpuInfos[7]) + Long.parseLong(cpuInfos[8]);
return totalCpu;
}</span>

AppCpuTime

private static long getAppCpuTime(int pid) { // 获取应用占用的CPU时间
String[] cpuInfos = null;
try {
// int pid = android.os.Process.myPid();
BufferedReader reader = new BufferedReader(new InputStreamReader(
new FileInputStream("/proc/" + pid + "/stat")), 1000);
String load = reader.readLine();
reader.close();
cpuInfos = load.split(" ");
} catch (IOException ex) {
ex.printStackTrace();
}
long appCpuTime = Long.parseLong(cpuInfos[13])
+ Long.parseLong(cpuInfos[14]) + Long.parseLong(cpuInfos[15])
+ Long.parseLong(cpuInfos[16]);
return appCpuTime;
}

public static float getProcessCpuRate(int pid) // 获得应用cpu占用率
{
float CPU = 0;
try {
float totalCpuTime1 = getTotalCpuTime();
float processCpuTime1 = getAppCpuTime(pid);
try {
Thread.sleep(300);
} catch (Exception e) {
}
float totalCpuTime2 = getTotalCpuTime();
float processCpuTime2 = getAppCpuTime(pid);
float cpuRate = 100 * (processCpuTime2 - processCpuTime1)
/ (totalCpuTime2 - totalCpuTime1);
String str = new DecimalFormat("0.00").format(cpuRate);
CPU = Float.parseFloat(str);
} catch (Exception e) {
}
return CPU;
}

以上读取方式都是采用bufferReader读取指定路径中的信息。这中方式简单易操作。   接下来给大家讲解另一种方式，读取CPU相关信息：在我项目中...........MyUtil类里。同样采用的是bufferReader。返回的是一个ArrayList集合，存放了多核的耗时总时间时间eg：cpu  cpu1 cpu2 cpu 3...........等。