Linux CPU utilization: Difference between revisions

<syntaxhighlight lang="java">

import java.io.BufferedReader;

import java.io.File;

import java.io.FileReader;

import java.io.IOException;

</syntaxhighlight>

<syntaxhighlight lang="java">

public static void main(String[] args) throws IOException {

double[] percentages = parseUtilization(procStat());

System.out.printf("%-10s %5.2f%%%n", "idle", percentages[0] * 100);

System.out.printf("%-10s %5.2f%%", "not-idle", percentages[1] * 100);

}

static String procStat() throws IOException {

File file = new File("/proc/stat");

try (BufferedReader reader = new BufferedReader(new FileReader(file))) {

return reader.readLine();

}

}

/** @return idle and not-idle percentage values */

static double[] parseUtilization(String string) {

string = string.substring(4).stripLeading();

int total = 0;

double idle = 0;

double notIdle;

int index = 0;

for (String value : string.split(" ")) {

if (index == 3)

idle = Integer.parseInt(value);

total += Integer.parseInt(value);

index++;

}

idle /= total;

notIdle = 1 - idle;

return new double[] { idle, notIdle };

}

</syntaxhighlight>

<pre>

idle 93.33%

not-idle 6.67%

</pre>

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An alternate demonstration