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一、原理

基于 /proc/meminfo 信息读取

/* /proc/meminfo        MemTotal:        2902436 kB        MemFree:          199240 kB        MemAvailable:    1088764 kB        Buffers:           40848 kB        Cached:           862908 kB        SwapCached:        54696 kB        Active:          1222848 kB        Inactive:         671468 kB        Active(anon):     758516 kB        Inactive(anon):   242560 kB        Active(file):     464332 kB        Inactive(file):   428908 kB        Unevictable:        5972 kB        Mlocked:             256 kB        SwapTotal:       1048572 kB        SwapFree:         537124 kB        Dirty:                12 kB        Writeback:             0 kB        AnonPages:        988820 kB        Mapped:           508996 kB        Shmem:              4800 kB        Slab:             157204 kB        SReclaimable:      57364 kB        SUnreclaim:        99840 kB        KernelStack:       41376 kB        PageTables:        51820 kB        NFS_Unstable:          0 kB        Bounce:                0 kB        WritebackTmp:          0 kB        CommitLimit:     2499788 kB        Committed_AS:   76292324 kB        VmallocTotal:   258867136 kB        VmallocUsed:           0 kB        VmallocChunk:          0 kB        CmaTotal:              0 kB        CmaFree:               0 kB    */

二、代码

package com.fadisu.cpurun.util;import java.io.BufferedReader;import java.io.FileReader;import java.io.IOException;import java.util.ArrayList;import java.util.List;import java.util.regex.Matcher;import java.util.regex.Pattern;public class MemInfoUtil {
       public static List
   
     getMemInfo() {        List
    
      result = new ArrayList<>();        try {            String line;            BufferedReader br = new BufferedReader(new FileReader("/proc/meminfo"));            while ((line = br.readLine()) != null) {                result.add(line);            }            br.close();        } catch (IOException e) {            e.printStackTrace();        }        return result;    }    /* /proc/meminfo        MemTotal:        2902436 kB        MemFree:          199240 kB        MemAvailable:    1088764 kB        Buffers:           40848 kB        Cached:           862908 kB        SwapCached:        54696 kB        Active:          1222848 kB        Inactive:         671468 kB        Active(anon):     758516 kB        Inactive(anon):   242560 kB        Active(file):     464332 kB        Inactive(file):   428908 kB        Unevictable:        5972 kB        Mlocked:             256 kB        SwapTotal:       1048572 kB        SwapFree:         537124 kB        Dirty:                12 kB        Writeback:             0 kB        AnonPages:        988820 kB        Mapped:           508996 kB        Shmem:              4800 kB        Slab:             157204 kB        SReclaimable:      57364 kB        SUnreclaim:        99840 kB        KernelStack:       41376 kB        PageTables:        51820 kB        NFS_Unstable:          0 kB        Bounce:                0 kB        WritebackTmp:          0 kB        CommitLimit:     2499788 kB        Committed_AS:   76292324 kB        VmallocTotal:   258867136 kB        VmallocUsed:           0 kB        VmallocChunk:          0 kB        CmaTotal:              0 kB        CmaFree:               0 kB    */    public static String getFieldFromMeminfo(String field) throws IOException {        BufferedReader br = new BufferedReader(new FileReader("/proc/meminfo"));        Pattern p = Pattern.compile(field + "\\s*:\\s*(.*)");        try {            String line;            while ((line = br.readLine()) != null) {                Matcher m = p.matcher(line);                if (m.matches()) {                    return m.group(1);                }            }        } finally {            br.close();        }        return null;    }    public static String getMemTotal() {        String result = null;        try {            result = getFieldFromMeminfo("MemTotal");        } catch (IOException e) {            e.printStackTrace();        }        return result;    }    public static String getMemAvailable() {        String result = null;        try {            result = getFieldFromMeminfo("MemAvailable");        } catch (IOException e) {            e.printStackTrace();        }        return result;    }}
    
   

三、运行结果

四、具体源码