oshi.util.platform.linux.ProcUtil Maven / Gradle / Ivy
/**
* Oshi (https://github.com/oshi/oshi)
*
* Copyright (c) 2010 - 2018 The Oshi Project Team
*
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Maintainers:
* dblock[at]dblock[dot]org
* widdis[at]gmail[dot]com
* enrico.bianchi[at]gmail[dot]com
*
* Contributors:
* https://github.com/oshi/oshi/graphs/contributors
*/
package oshi.util.platform.linux;
import java.io.File;
import java.io.FileFilter;
import java.util.regex.Pattern;
import oshi.util.FileUtil;
/**
* Provides access to some /proc filesystem info on Linux
*
* @author widdis[at]gmail[dot]com
*/
public class ProcUtil {
private static final Pattern DIGITS = Pattern.compile("\\d+"); // NOSONAR-squid:S1068
private ProcUtil() {
}
/**
* Parses the first value in /proc/uptime for seconds since boot
*
* @return Seconds since boot
*/
public static float getSystemUptimeFromProc() {
String uptime = FileUtil.getStringFromFile("/proc/uptime");
int spaceIndex = uptime.indexOf(' ');
try {
if (spaceIndex < 0) {
// No space, just parse
return Float.parseFloat(uptime);
} else {
return Float.parseFloat(uptime.substring(0, spaceIndex));
}
} catch (NumberFormatException nfe) {
return 0f;
}
}
/**
* Gets an array of files in the /proc directory with only numeric digit
* filenames, corresponding to processes
*
* @return An array of File objects for the process files
*/
public static File[] getPidFiles() {
File procdir = new File("/proc");
File[] pids = procdir.listFiles(new FileFilter() {
@Override
public boolean accept(File file) {
return DIGITS.matcher(file.getName()).matches();
}
});
return pids != null ? pids : new File[0];
}
}