jcmd(1)jcmd(1)Name
jcmd - Diagnostic Command
jcmd is a utility to send diagnostic command requests to a running Java
Virtual Machine.
SYNOPSIS
jcmd [ option ]
jcmd <pid | main class> PerfCounter.print
jcmd <pid | main class> command [arguments]
jcmd <pid | main class> -f file
DESCRIPTION
jcmd is a utility to send diagnostic command requests to a Java Virtual
Machine supporting this feature.
Used without arguments or with the -l option, jcmd prints the list of
running Java processes with their process id, their main class and
their command line arguments.
When a process id is specified on the command line, jcmd sends the
diagnostic command request to the process with this id.
When a main class is specified on the command line, jcmd sends the
diagnostic command request to all Java processes for which the command
line argument is a substring of the Java process' main class.
With the PerfCounter.print argument, jcmd prints the performance coun‐
ters available on the targeted Java process(es).
With the -f option, jcmd sends to the targeted Java process(es) the
diagnostic commands stored in the file file.
OPTIONS
Options are mutually exclusive. Options, if used, should follow immedi‐
ately after the command name.
-l Prints the list of running Java processes with their process id,
their main class and their command line arguments.
-h Prints a help message.
-help
Prints a help message.
PARAMETERS
pid
Identifies the process that receives the diagnostic command
requests. The process must be a Java process. To get a list of
Java processes running on a machine, use jps(1) or jcmd(1).
main class
Main class of the process that receives the diagnostic command
requests. When matching processes, any process whose main class
name contains the specified string as a substring will be
matched. If several running Java processes share this main class,
the diagnostic command request is sent to all these processes. To
get a list of Java processes running on a machine, use jps(1) or
jcmd(1).
command [arguments]
Invoke the diagnostic command called command on the targeted Java
process(es). The list of available diagnostic commands for a
given process can be obtained by invoking the help command on
this process. Each diagnostic command has its own set of argu‐
ments, which can be obtained by invoking the the command name
followed by help.
PerfCounter.print
Print the performance counters available on the targeted Java
process(es). The list of performance counters may vary with the
Java process.
-f file
Read commands from file and invoke them on the targeted Java
process(es). In file, each command must be written on a single
line. Lines starting with # are ignored. Processing of file ends
when all lines have been invoked or when a line containing the
stop keyword is read.
SEE ALSO
o jps(1)jps(1)
10 Jul 2012 jcmd(1)
