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1.参考文档

2.源码下载

3.思路

获取”/proc/stat”的运行时间，使用CPU 使用率 =(CPU 非空闲时间2 - CPU 非空闲时间1) / (CPU 运行总时间2 - CPU 运行总时间1) * 100%计算

4.实现代码

package com.fadisu.cpurun.util;import android.os.Process;import java.util.ArrayList;import java.util.List;/** * ProcCpuStatUtil analysis */public class ProcCpuStatUtil {
       private static final String TAG = ProcCpuStatUtil.class.getSimpleName();    // ProcCpuStatUtil probe    private static final int[] SYSTEM_CPU_FORMAT = new int[]{            Process.PROC_SPACE_TERM | Process.PROC_COMBINE,            Process.PROC_SPACE_TERM | Process.PROC_OUT_LONG, // 1: user time            Process.PROC_SPACE_TERM | Process.PROC_OUT_LONG, // 2: nice time            Process.PROC_SPACE_TERM | Process.PROC_OUT_LONG, // 3: sys time            Process.PROC_SPACE_TERM | Process.PROC_OUT_LONG, // 4: idle time            Process.PROC_SPACE_TERM | Process.PROC_OUT_LONG, // 5: iowait time            Process.PROC_SPACE_TERM | Process.PROC_OUT_LONG, // 6: irq time            Process.PROC_SPACE_TERM | Process.PROC_OUT_LONG  // 7: softirq time    };    public static List
   
     getCpuTime() {        List
    
      result = new ArrayList<>();        long[] sysCpu = new long[7];        if (Process.readProcFile("/proc/stat", SYSTEM_CPU_FORMAT, null, sysCpu, null)) {            result.add("User time : " + DateTimeUtil.longToSting(sysCpu[0]));            result.add("Nice time : " + DateTimeUtil.longToSting(sysCpu[1]));            result.add("Sys time : " + DateTimeUtil.longToSting(sysCpu[2]));            result.add("Idle time : " + DateTimeUtil.longToSting(sysCpu[3]));            result.add("Iowait time : " + DateTimeUtil.longToSting(sysCpu[4]));            result.add("Irq time : " + DateTimeUtil.longToSting(sysCpu[5]));            result.add("Softirq time : " + DateTimeUtil.longToSting(sysCpu[6]));            long totalCpuTime = sysCpu[0] + sysCpu[1] + sysCpu[2] + sysCpu[3] + sysCpu[4] + sysCpu[5] + sysCpu[6];            result.add("Total CPU time : " + DateTimeUtil.longToSting(totalCpuTime));        }        return result;    }    public static class CpuRateInfo {
           // CPU 运行总时间        double totalCpuTime;        // CPU 空闲时间        double idleTime;        // CPU 非空闲时间        double nonIdleTime;    }    public static CpuRateInfo getCpuRateInfo() {        CpuRateInfo mCpuRateInfo = new CpuRateInfo();        long[] sysCpu = new long[7];        if (Process.readProcFile("/proc/stat", SYSTEM_CPU_FORMAT, null, sysCpu, null)) {            mCpuRateInfo.idleTime = sysCpu[3];            mCpuRateInfo.totalCpuTime = sysCpu[0] + sysCpu[1] + sysCpu[2] + sysCpu[3] + sysCpu[4] + sysCpu[5] + sysCpu[6];            mCpuRateInfo.nonIdleTime = mCpuRateInfo.totalCpuTime - mCpuRateInfo.idleTime;        }        return mCpuRateInfo;    }    /**     * 获取 CPU 使用率     * CPU 使用率 =(CPU 非空闲时间2 - CPU 非空闲时间1) / (CPU 运行总时间2 - CPU 运行总时间1) * 100%     * https://www.jianshu.com/p/6bf564f7cdf0     */    public static String getCpuUsage() {        String result = null;        CpuRateInfo mCpuRateInfo1 = getCpuRateInfo();        try {            Thread.sleep(2000);        } catch (InterruptedException e) {            e.printStackTrace();        }        CpuRateInfo mCpuRateInfo2 = getCpuRateInfo();        double usage = ((mCpuRateInfo2.nonIdleTime - mCpuRateInfo1.nonIdleTime) / (mCpuRateInfo2.totalCpuTime - mCpuRateInfo1.totalCpuTime)) * 100;        result = String.valueOf((int) usage) + "%";        return result;    }}
    
   

5.实现代码

运行结果