Package oshi.driver.linux.proc

Class ProcessStat

java.lang.Object

oshi.driver.linux.proc.ProcessStat

@ThreadSafe
public final class ProcessStat
extends Object

Utility to read process statistics from /proc/[pid]/stat

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static enum	ProcessStat.PidStat	Enum corresponding to the fields in the output of /proc/[pid]/stat
static enum	ProcessStat.PidStatM	Enum corresponding to the fields in the output of /proc/[pid]/statm

Field Summary

Fields

Modifier and Type	Field	Description
static final int	PROC_PID_STAT_LENGTH	Constant defining the number of integer values in /proc/pid/stat. 2.6 Kernel has 44 elements, 3.3 has 47, and 3.5 has 52.

Method Summary

Modifier and Type	Method	Description
static File[]	getFileDescriptorFiles(int pid)	Gets an array of files in the /proc/{pid}/fd directory.
static File[]	getPidFiles()	Gets an array of files in the /proc directory with only numeric digit filenames, corresponding to processes
static Map<ProcessStat.PidStatM,Long>	getPidStatM(int pid)	Reads the statistics in /proc/[pid]/statm and returns the results.
static Triplet<String,Character,Map<ProcessStat.PidStat,Long>>	getPidStats(int pid)	Reads the statistics in /proc/[pid]/stat and returns the results.
static OSProcess.State	getState(char stateValue)	Returns Enum STATE for the state value obtained from status file of any process/thread.
static List<Integer>	getThreadIds(int pid)	Gets a List of thread ids for a process from the /proc/[pid]/task/ directory with only numeric digit filenames, corresponding to the threads.
static Map<Long,Integer>	querySocketToPidMap()	Gets a map of sockets and their corresponding process ID

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details

PROC_PID_STAT_LENGTH

public static final int PROC_PID_STAT_LENGTH

Constant defining the number of integer values in /proc/pid/stat. 2.6 Kernel has 44 elements, 3.3 has 47, and 3.5 has 52.

Method Details

getPidStats

public static Triplet<String,Character,Map<ProcessStat.PidStat,Long>> getPidStats(int pid)

Reads the statistics in /proc/[pid]/stat and returns the results.

Parameters:

pid - The process ID for which to fetch stats

Returns:

A triplet containing the process name as the first element, a character representing the process state as the second element, and an EnumMap as the third element, where the numeric values in ProcessStat.PidStat are mapped to a Long value.

If the process doesn't exist, returns null.

getPidStatM

public static Map<ProcessStat.PidStatM,Long> getPidStatM(int pid)

Reads the statistics in /proc/[pid]/statm and returns the results.

Parameters:

pid - The process ID for which to fetch stats

Returns:

An EnumMap where the numeric values in ProcessStat.PidStatM are mapped to a Long value.

If the process doesn't exist, returns null.

getFileDescriptorFiles

public static File[] getFileDescriptorFiles(int pid)

Gets an array of files in the /proc/{pid}/fd directory.

Parameters:

pid - id of process to read file descriptors for

Returns:

An array of File objects representing opened file descriptors of the process

getPidFiles

public static File[] getPidFiles()

Gets an array of files in the /proc directory with only numeric digit filenames, corresponding to processes

Returns:

An array of File objects for the process files

querySocketToPidMap

public static Map<Long,Integer> querySocketToPidMap()

Gets a map of sockets and their corresponding process ID

Returns:

a map with socket as the key and pid as the value

getThreadIds

public static List<Integer> getThreadIds(int pid)

Gets a List of thread ids for a process from the /proc/[pid]/task/ directory with only numeric digit filenames, corresponding to the threads.

Parameters:

pid - process id

Returns:

A list of thread id.

getState

public static OSProcess.State getState(char stateValue)

Returns Enum STATE for the state value obtained from status file of any process/thread.

Parameters:

stateValue - state value from the status file

Returns:

OSProcess.State